Skip to main content
Future Journal of Pharmaceutical Sciences
Download PDF

A critical analytical aspect on analytical protocols in the pharmaceutical analysis of H1N1 antiviral agent and its active metabolite

Future Journal of Pharmaceutical Sciences volume 10, Article number: 110 (2024) Cite this article

Abstract

Background

Oseltamivir (OSM) was the first active oral therapeutic inhibitor approved by the Food and Drug Administration in 1999 for the clinical management of the influenza virus. It is an ester-type prodrug of OSM carboxylate in the market under the trade name Tamiflu™ capsules, i.e., oseltamivir phosphate. Because of the ubiquitous application to alleviate influenza virus (flu virus) symptoms, it is imperative to develop systematic analytical protocols for quality control laboratories, bioequivalence, and pharmacokinetic analysis.

Main body of the abstract

This review provides complete state-of-the-art analytical protocols for quantifying OSM, as published in scientific journals and official compendia. Several studies use LC–MS/MS and HPLC/UV. Additionally, there are reports on UPLC, HPTLC, capillary electrophoresis, FTIR, voltammetry, potentiometry, spectrophotometric, and spectrofluorometry protocols for the drug. Many analytical protocols have also been documented to analyze OSM from environmental water, surface water, sewage discharge, the Neya River and treated sewage effluent and surface water.

Conclusion

The present review concludes with significant remarks on the methodology used to analyze OSM. Despite the therapeutic applicability of the drug, there are a limited number of comprehensive documents on analytical protocols for determining its concentration in various matrices. This lack of information is elusive, as the applicability and effectiveness of these protocols are crucial for ensuring the quality, efficacy, and safety of OSM.

Background

Influenza is a highly acute infectious respiratory tract illness resulting from types A and B of influenza virus species. It spreads through droplets released when an infected person coughs or sneezes [1]. The symptoms of the disease can range from mild to severe, affecting the respiratory system and other organs. Influenza can be particularly dangerous for young or elderly individuals with weakened immune systems or those with underlying health conditions, such as heart or lung diseases [2,3,4,5,6,7].

In 1969, P. Meindl and H. Tuppy developed the first inhibitor of influenza virus neuraminidase (IVN), which stopped virus replication; however, it had low potency and specificity. In 1993, scientist Von Itzstein and colleagues reported Zanamivir (ZMV) as a specific and potent IVN inhibitor that stopped the spread of the virus in both in vitro and in vivo studies. This development was demonstrated after the crystalline structure of IVN and its complex with neuraminic acid was reported by P. M. Colman and the research team in the 1980s [4, 8]. OSM was the first orally active inhibitor, documented in 1997 by Kim and research workers. In 1999, the Food and Drug Administration (FDA) approved the OSM for clinical use in various countries, such as the USA, Canada, Switzerland, and many other parts of the world [9]. The compound OSM, previously known as GS4104 or RO-0796, is an ester-type prodrug of oseltamivir carboxylate (OSM-C), formerly known as GS4071 or RO64-08022. OSM is a modified antiviral generic version available in the market under the Tamiflu trade name, specifically oseltamivir phosphate (OSM-P). It has been proven to be an effective treatment for seasonal influenza, reducing the severity and duration of the illness. Studies have shown that OSM-C is 3–4 times more potent as an inhibitor than ZMV. In vitro, assessments have indicated that it is at least 106 times more selective for influenza virus (neuraminidases) than for parainfluenza virus, Newcastle disease virus, Vibrio cholerae, Clostridium perfringens, and human liver microsomes.

Despite its strong history, OSM has been the preferred neuraminidase inhibitor for the past two decades due to its prophylactic and therapeutic status. Scientists and academicians must comprehensively understand the latest updates for their professional and learning pursuits. Therefore, this review aims to briefly overview commonly used analytical protocols for detecting OSM in various samples and highlight the experimental conditions required for analysis. The second objective is to offer readers a wealth of analytical knowledge on the selected topic and emphasize essential background information such as physicochemical properties, chemistry, pharmacodynamics, and pharmacokinetic characteristics of OSM.

Physiochemical properties of OSM

OSM (CAS number-196618-13-0): Chemically, it is ethyl(3R,4R,5S)-4-acetamido-5-amino-3-pentan-3-yloxycyclohexene-1-carboxylate. It has a molecular formula of C16H28N2O4 and a molecular weight of 312.4 g/mol. Its melting point is 190–206 °C, and its pKa and log p value are 1.0 and 7.7 at 25 °C. OSM-P is freely soluble in H2O (water) and MeOH (methanol) and practically insoluble in methylene chloride [10, 11]. The structure of OSM and its active metabolite are depicted in Fig. 1A and B. The structure of OSM is altered based on the amino acid coordinates that bind with the glycerol chain of 2-deoxy-2,3-didehydro-N-acetylneuraminic acid. OSM has been studied to develop new inhibitors with hydrophobic groups [4, 12,13,14]. Its structure contains a cyclohexene ring with three stereogenic centers, mainly C3, C4, and C5, which are chiral carbon atoms, resulting in eight stereoisomers. C3 is bound to a 3-pentoxy group, C4 to an acetamine, and C5 is attached to an –NH2 group. OSM-P has a specific (3R, 4R, 5S) configuration [15,16,17].

Fig. 1
figure 1

Chemical structure of OSM [A] and active metabolite OSM-C [B]

Full size image

Pharmacology of OSM

Neuraminidase inhibitors (NI) have been developed for prophylactic and therapeutic purposes against influenza in recent years. These inhibitors deliberately target the highly conserved viral enzyme surface area. The first kind of inhibitor to undergo a clinical trial is ZMV, which is not active when taken orally. Therefore, it is administrated through dry powder inhalation to the lungs. The hydrophobic side chain on OSM-C interacts with a hydrophobic pocket at the virus enzyme's active site. This binding prevents the enzyme from cleaving sialic acid residues on the surface of infected cells, inhibiting the release of new virus particles from the infected cells [18, 19]. In healthy volunteers, OSM-C reaches detectable levels in the bloodstream within 30 min after a single oral dose and is efficiently absorbed in the gastrointestinal tract.

The peak concentration of OSM-C in the bloodstream was reached 3–4 h after consumption. The oral bioavailability was high, at about 79% for a 150 mg dose compared to an intravenous dose. In a crossover and randomized study involving 18 volunteers, it was found that food did not significantly affect the absorption of OSM. However, the time taken to reach peak concentration (Cmax) or the total drug exposure (AUC) was delayed by 1 h [19, 20]. When OSM-C was administered intravenously, it was distributed into most body fluids. The volume of distribution at steady-state is 25.6L, equal to the total body water. OSM has a protein binding of 42% in human plasma specimens, while OSM-C has a protein binding of 3%. OSM is extensively metabolized through hepatic esterases, and OSM-C is primarily eliminated through renal excretion, involving both glomerular filtration and anionic renal tubular secretion. After administering a single oral dose of OSM ranging from 20 to 1000 mg, a mean renal clearance value of 21.7 L/h was recorded in healthy adult volunteers.

Approximately 63% of OSM-C was recovered from urine after intake of a 100 mg dose, and it was observed that about 20% of an oral dose of OSM was excreted in feces as either OSM or unchanged OSM. OSM-C clearance was found to be relatively slower in older individuals (around 65 years old) and much quicker in children (around 12 years old) compared to adults. In patients with severe kidney problems, OSM-C clearance was reduced [21, 22]. OSM is recommended at a dose of 75 mg (twice a day) for five consecutive days, with or without food, for adolescent and adult patients of all ages. Treatment should start within two days of the onset of symptoms. For infected patients with creatinine clearance less than 1.8 L/h (< 30 mL/min), a reduced dose of 75 mg once daily is recommended. Extra caution is needed for patients with creatinine clearance less than 0.6 L/h (< 10 mL/min). In the elderly, no dosage adjustment is required [18, 19, 23]. A 12 mg/mL oral suspension is prescribed for children with influenza (older than 1 year) or adult patients who cannot swallow a capsule. In healthy adults, two doses of 75 mg of OSM for five consecutive days efficiently reduced the duration of naturally acquired influenza by 1.3–1.5 days and decreased the severity of illness by up to 38%. Common side effects include nausea, vomiting, dizziness, headache, diarrhea, nosebleeds, cough, redness of the eye, and insomnia [24].

A search of the state of the art for published reports on OSM

Numerous analytical reports on both qualitative and quantitative estimations of OSM from various samples are available. To review the research results and findings based on the gathered information, a literature analysis has been conducted using keywords such as IVN, bioanalytical protocols for OSM, and analytical protocols for OSM. This analysis involved selected methodologies, including hyphenated, spectroscopic, electrochemical, and chromatographic techniques, along with current issues of periodicals, citations of research and review articles and library database searches. Various academic search engines such as Google Scholar, Scopus, EBSCO, Analytical Sciences Digital Library, ProQuest Central, Web of Science, Semantic Scholar, and ScienceDirect were utilized. Examination of reports in the literature highlighted that a good percentage of analytical reports are available to determine OSM from diverse specimens. These investigations have their strengths and limitations. Over the past few years, many advancements and enhancements have been made to establish and validate analytical protocols for assessing the purity and quantification of a cited drug from various pharmaceutical or non-pharmaceutical specimens.

These protocols provide valuable data for analytical chemists to choose the most suitable protocol for their intended use. Regardless of the purpose for which the protocol was developed and validated, there is a constant need to improve these protocols. This includes enhancing the analytical response, implementing better sample preparation procedures, reducing the overall analysis time, minimizing toxic solvents and reagents, and adopting protocols that generate less hazardous waste materials. Developing an analytical protocol is challenging for analytical chemists or scientists/researchers because when the protocol is redeployed to other laboratories, it needs to be robust, precise, and accurate. Therefore, a proposed review would benefit researchers, analysts, and scientists by helping them develop new, rapid, robust analytical protocols for OSM.

Analytical profile of OSM

Several analytical reports have been addressed in the literature since 1999 to estimate OSM individually. Here, we have categorized these published reports into two main classes: pharmacopoeial and non-pharmacopoeial reports.

Compendial analytical reports on OSM

Analytical protocols for OSM are officially addressed in the Indian Pharmacopoeia, British Pharmacopoeia, and United States Pharmacopeia.

Indian pharmacopoeia

The liquid-chromatographic (LC) protocol evaluated the OSM from capsule and oral suspension forms. The chromatographic conditions included a stainless steel column measuring 15 cm × 4.6 mm, packed with octylsilane bonded to porous silica (5 μm). The column temperature was set at 50 °C. The mobile phase consisted of a mixture of 66 volumes of a buffer solution prepared by dissolving 6.8 g of anhydrous monobasic potassium phosphate in 1000 mL of water and adjusting the pH to 6.0 with dilute sodium hydroxide, 24.5 volumes of methanol (MeOH), and 23.5 volumes of acetonitrile (ACN). The flow rate was maintained at 1.0 mL/min, and detection was performed at 207.0 nm using a spectrophotometer. A sample volume of 15 μL was injected into the system [10].

British pharmacopoeia

The British Pharmacopoeia (BP) reported analytical protocols for analyzing OSM impurities. Table 1 depicts eight official impurities (A to H) documented in BP.

Table 1 Impurities and related substances of OSM in Compendial Analytical Methodologies
Full size table

OSM-Impurity-A and C

The LC was used to detect impurities A and C. The analysis was conducted using end-capped octylsilyl silica gel for chromatography R (5 μm), with a mixture of ACN: MeOH: potassium dihydrogen phosphate (135:245:620v/v), a flow rate of 1.2 mL/min, a column temperature of 50 °C, and detection at 207.0 nm using a spectrophotometer. The test solution and reference were injected at a volume of 15 μL.

OSM-Impurity-B

The LC–MS was conducted to analyze impurity-B. The experiment utilized an end-capped octadecylsilyl silica gel for chromatography R (5 μm) column with a mobile phase comprised of ammonium acetate (AmAc): ACN: H2O (10:30:60%v/v). The flow rate was 1.5 mL/min, with the column temperature at 40 °C. A mass detector with an ESI-positive ionization source was employed, and the detection was performed at m/z 356.2. The injection volution used was 1.0 μL.

OSM-Impurity-H

Gas chromatography (GC) estimates impurity-H under specific working conditions. These conditions include a poly(dimethyl)siloxane column, helium carrier gas with a flow rate of 1.2 mL/min and a split ratio 1:50. The analysis uses a flame ionization detector, and the injection volume is 1.0 μL [11].

United States pharmacopeia

The chromatographic conditions were as a column measuring 25 cm\(\times\)4.6 mm packed with L7. The column temperature was maintained at 50 °C. The mobile phase consisted of a mixture of MeOH: ACN: sample solution A. Sample solution A was prepared by dissolving 6.8 g of potassium dihydrogen phosphate in 980 mL of H2O, adjusting the pH to 6.0 using 1.0 M potassium hydroxide solution and then completing the volume to 1.0 L. The ratio of mobile phase components was 243:135:620v/v. The flow rate was set at 1.2 mL/min, and detection was performed at 207.0 nm using a UV detector. A sample volume of 15 μL was injected into the system [25].

Non-compendial analytical reports on OSM

Scientists, research scholars, and academicians have developed various non-pharmacopoeial protocols to accurately determine OSM in different matrices, in addition to pharmacopoeial protocols. The following section offers an overview of these non-pharmacopoeial protocols.

Hyphenated protocols

Hyphenated techniques are crucial for analyzing unknown organic compounds or medicinal candidates in natural extracts and biological specimens. The proposed roadmap addressed different hyphenated techniques, namely LC–MS/MS, GC–MS, and UHPLC-MS/MS, to evaluate OSM from different sources. Table 2 provides detailed information on the pharmaceutical/biological specimen, extraction technique, internal standard, operational conditions, interface, mass-to-charge ratio, and total analysis time, supporting our findings validity. This summary highlights several hyphenated investigations. Kanneti, R. et al. reported reliable and rugged solid-phase extraction (SPE) LC–MS/MS protocol. The authors have validated the protocols using 500 μL plasma samples with 0.6 mL/min isocratic flow rate and 1.0 min as total run time. The lower limit of quantitation (LLOQ) was recorded at 0.92, 5.22 ng/mL for the lowest concentration of standard curves, i.e., 0.92–745.95 for OSM and 5.22–497.49 ng/mL for OSM-C [26]. Zhe-Yi Hu et al. improved the performance of the OSM and OSM-C assay in human plasma by using a pulsed gradient chromatographic protocol. They used sodium fluoride to inhibit esterase activity and prevent hydrolysis during sampling, ensuring the stability of the analyte [27]. Gupta et al. studied high-throughput simultaneous bioanalysis of OSM and OSM-C with the aid of SPE using OSM-d5 and OSM-C13-d3 as internal standard (IS) in human plasma. The retention time (tR) for both cited analytes was 1.56 and 1.11 min, respectively. Moreover, the extraction recovery average for targeting analytes was 94.4%, 92.4%, 93.1%, and 91.9%, correspondingly [28]. Kromdijk et al. conducted ex vivo stability studies on OSM and OSM-C in human fluoride EDTA plasma and confirmed that OSM remains stable in whole blood in EDTA fluoride tubes for 8 h at 37 °C and for 24 h at 2–8 °C [29]. Several reports have been highlighted, analyzing selected therapeutics in multiple biological specimens such as urine, saliva, cerebrospinal fluid, brain homogenate, and plasma from humans and rats [30,31,32].

Table 2 Overview on LC–MS/MS analysis conditions for OSM
Full size table

Heinig and Bucheli developed a reliable method to estimate OSM and OSM-C levels in both rat and human specimens. The mean recoveries were close to 100% for rat plasma and human samples, ranging from 83.3 to 100.9% for cerebrospinal fluid and brain samples. OSM and OSM-C solutions remained stable for 24 h at room temperature and 4 weeks at  − 20 °C for brain homogenate and plasma [30]. UPLC-MS/MS protocol is documented to estimate 14 antiviral agents simultaneously along with OSM and OSM-C in chicken muscle tissues. The recovery rates of the proposed investigation are 56.2–113.4% with 1.7–10.3% RSD [33]. Hoff, G. P., along with the research team, conducted analysis on the dried blood spots. The 5–1500 ng/mL linearity range and 20–1500 ng/mL were recorded for OSM and OSM-C, correspondingly with gradient elution followed by cited drugs eluted at 1.88 and 3.20 min [34]. Wu et al. explored the application of UHPLC-MS/MS to estimate the 11 antiviral agents (prohibited) from livestock and poultry feces. The study proposed a method that integrated extraction and cleanup into a single step. It involved extracting the same agents at a temperature of 90 °C using a mixture of MeOH and ACN in a 1:1 volume ratio, along with 0.5% glacial acetic acid. Researchers reported 71.5–112.5% extraction recoveries of 11 antiviral agents [35]. Two LC–MS/MS protocols were reported in the literature to quantify cited drugs from poultry tissues and muscle. In both protocols, a gradient mode of analysis was performed using 50 mM FA in H2O (A) and 50 mM FA in ACN (B) [36].

Lin, C.C., and the research team analyzed OSM and OSM-C in the placenta, amniotic fluid, fetus, and plasma of 13 day pregnant rats, finding the AUC of OSM-C in maternal plasma was 3.6-fold higher than OSM. They used modified SPE protocols with isocratic elution and studied pharmacokinetics with non-compartmental modeling [38].

From the survey for a roadmap of present work, it was noticed that there are also several hyphenated reports available on scholarly sources for analysis of OSM and its active metabolite from environmental water, surface water, sewage discharge, Neya River, and treated sewage effluent and surface water [40,41,42,43,44,45]. In addition, another robust analytical technique, i.e., GC–MS application, was also documented in the literature for synergistic efficacy of a cited drug and Melissa officinalis essential oil. The authors reported that the estimation of volatile was executed on DB-IMS (30 m \(\times\) 0.25 mm, 0.25 μm film thickness) using helium at 1.2 mL/min carrier gas rate of flow and 250 °C injection temperature [54]. There is only one report available on GC–MS due to its limitations. It can only analyze volatile samples and is unsuitable for thermally stable active agents. Additionally, careful attention is required when introducing gas samples.

Chromatographic protocols

Chromatographic techniques have been the primary method to assess pharmaceutical effectiveness in the past two decades. High-performance liquid-chromatography (HPLC) is acknowledged as a dominant analytical tool but is still the subject of ongoing research to enhance performance and accuracy. From 1999 to 2021, researchers commonly used HPLC with UV-visible, photodiode array, fluorescence, and mass spectrometry detection for the pharmaceutical analysis of OSM and its metabolites. C18 is widely used in all HPLC reports for its longer carbon chain, hydrophobic nature, and interaction with analytes. ACN and MeOH are the most commonly used eluents and various buffer solutions. The most commonly reported HPLC–UV-visible detection wavelength is 207–254 nm, and 8 out of 13 quantifications were performed at 215 and 220 nm. Only one experiment was performed using fluorescent HPLC detection. The detailed chromatographic report specification for pharmaceutical analysis of OSM is presented in Table 3.

Table 3 Chromatographic reports for pharmaceutical analysis of OSM
Full size table

Charles and his colleagues have reported a reliable and rapid protocol for analyzing OSM in marketed capsules (Tamiflu and generic versions) using UV detection with a short elution time of less than 5 min. Sotalol hydrochloride was employed as the IS, and the average tR of the cited analytes were 3.34 ± 0.03 and 2.27 ± 0.02, respectively. The calibration range was 30–70 µg/mL, and the mean recovery was 100.01–102.28% [55]. Similarly, Green et al. performed calorimetric and HPLC protocols to test OSM alleged Tamiflu formulation [56]. Analysis of cited drug was also performed by Chabai et al. using monolithic column [57]. Four HPLC investigations have been addressed in the literature to quantify OSM in biological samples. Aydoğmuş et al. studied the reaction of 4-chloro-7-nitrobenzofurazan with OSM in a borate buffer solution at pH 8.50 and further quantified the same from the capsule and human plasma matrices with mexiletine hydrochloride as IS. OSM's LOD and LOQ were 5.70 and 17.38 ng/mL from plasma. Further, 99.95% amount of the drug was estimated from capsules [60]. Bahrami et al. use the procedure of SPE to extract OSM and OSM-C from human serum with a short run time < 10 min. The 98 ± 3% OSM-C and 85 ± 5% vanillin (IS) were extraction efficiencies from serum, and the proposed protocol is sensitive enough with 15 ng/mL of LOQ [61]. On the same line, Fuke & co-researcher explored HPLC with UV detection to quantify OSM and OSM-C with floropipamide (IS) from biological materials (in case of death). All analytes were extracted through a cation exchange extraction cartridge [62]. Five stability-indicating protocols were addressed for OSM using HPLC. Al-Bagary et al. reported alkaline degradation of OSM with the kinetic study. The degradation study was performed by exposing OSM to 0.1 M NaOH (10 mL) for 3 h [64]. In a separate study, researchers reported that OSM is degraded in 0.05 N NaOH for 5 h (25% degradation), 1 N HCl at 85 °C for 25 min (10% degradation), 30% H2O2 at 90 °C for 10 min (39% degradation). Whereas in thermal degradation, subjecting solid OSM at 120 °C for 1 h (22% degradation was observed) [65]. The chemical stability of OSM in an oral solution consisting of sodium benzoate (preservative) was studied using HPLC by Albert & Bockshorn [67]. Rashed et al. document a stability-indicating UPLC protocol; a calibration curve was constructed in the 6–14 µg/mL range with 0.150 and 0.501 µg/mL LOD, and LOQ values were detected and quantified. The OSM was effective with 100.79 ± 1.23% from the pharmaceutical matrix [69].

Two HPTLC investigations were found for OSM in the literature. HPTLC is an often analytical tool with many benefits relative to other analytical tools, including the small volume of developmental phase needed and the rapid and low-cost analysis [70]. A researcher reported the HPTLC protocol for assessment of OSM in pharmaceutical formulation counterfeited with ascorbic acid using (6.0:4.0:0.05v/v) MeOH: H2O: ammonia with retention factor (Rf) 0.70 and 0.83 for OSM and ascorbic acid. The OSM recovered from Taminil-N capsules was 102.51 ± 2.49% [71].

Spectrophotometric and spectrofluorometry

The spectrophotometric technique remains simple, cost-effective, and comparable to other analytical techniques in terms of instrumentation, analysis time, less sample processing time, and reduced use of hazardous organic solvents. It is commonly used to measure various therapeutic agents in pure materials and pharmaceutical formulations [72]. Twelve reports in the literature have estimated OSM using spectrophotometry and spectrofluorometry. These reports involve zero-order (D0), first-order (D1), ratio derivative, and difference spectrophotometry [58, 74, 75]. Because the OSM is poorly absorbed in the UV-visible region, the authors were able to study its colorimetric reaction.

Several colorimetric reactions were used to detect OSM. These reactions involve congo red and bromochlorophenol blue salt [56], 7,7,8,8-tetracyanoquinodimethane [73], alkaline potassium permanganate (KMnO4) [76, 77], lemieux reagent [77], 1, 2-naphthoquinone-4-sulfonic acid (NQS) [78], and 4-chloro-7-nitrobenzo-2-oxo-1,3-diazole (NBD-Cl) [79]. Additionally, there have been four spectrofluorimetric reports on OSM. Nebsen, M. et al. monitored the reaction of OSM with NBD-Cl at an alkaline medium (pH 9) [79]. Aydoğmuş Z. has presented a highly accurate method, a fluorescent derivative of OSM, using fluorescamine in a borate buffer solution (pH 8.50). This method, which uses a less toxic organic compound and solvent than previously reported protocols, allows for the precise determination of OSM in an aqueous solution. As there is no need for extraction, OSM can be determined accurately in an aqueous solution and is stable for around 6 h [80]. In another study, the Hantzsch reaction was carried out using acetylacetone and formaldehyde with the –NH2 group [81]. The sample specification, protocol, diluent, detection wavelength, linearity, LOD, LOQ, and % recovery are presented in Table 4.

Table 4 Spectral parameters of spectrophotometry and spectrofluorometry reports
Full size table

Miscellaneous analysis

ABOUL-ENEIN, Y. addressed single FTIR analysis using partial least squares (PLS) and principal component regression (PCR) chemometric tactics to determine OSM. Using PLS and PCR, the percentage amounts were 103.44 and 103.13% in the marketed TAMINIL-N matrix [83]. Tong et al. have reported the photolysis of an aq. solution of OSM using an advanced oxidation process (UV alone, UV/H2O2, and UV/H2O2/FeII). The crude photoproducts of OSM were analyzed using nuclear magnetic resonance, mass spectrophotometry, and HPLC [84].

Jabbaribar et al. conducted a study on the determination of micellar electrokinetic chromatography in Tamiflu capsules and OSM-C. The study used 10 mM of boric acid (pH 10) and 40 mM sodium dodecyl sulfate as background electrolytes [85]. The capillary electrophoresis protocol in capsule specimens involved using a fused silica capillary. The analytes were resolved by applying a potential of − 15 kV at 25 °C using a 50 mM sodium phosphate electrophoretic buffer of pH 6.3 and 226 nm UV detection. The LOD and LOQ values were 0.97 and 3.24 µg/mL [86]. Hamza et al. addressed the ion-selective electrode approach. They used polyvinyl chloride (PVC) as a membrane biosensor for developing ion association complexes of OSM cation with sodium tetraphenylborate-OSM, tungestosilisate-OSM, phosphomolybdate-OSM, and phosphotungstate-OSM as ion exchange positions in the PVC matrix [87]. Pop et al. documented a study on eight microelectrodes based on zinc complexes with porphyrins or phthalocyanines immobilized in carbon or diamond paste matrices. These electrodes were proposed to assay OSM's pharmaceutical formulation using differential pulse voltammetry (DPV). The LOD ranged between 3.64 × 10−14 and 8.17 × 10−9 mol/L. [88]. In addition, Avramov Ivić et al. reported a cyclic voltammetry protocol using a gold electrode in 0.05 M sodium bicarbonate in Tamiflu capsules [89]. Two potentiometric methods are under investigation for analyzing OSM in biological and pharmaceutical samples. Hassan and colleagues developed a PVC matrix membrane plasticized with o-nitrophenyloctyl ether, incorporating an ion association complex of OSM with the electroactive material phosphomolybdate anion [90]. Jebali and Belgaied established ion-pair complexes using new-coated platinum selective electrodes with plasticized PVC membranes doped based on phosphomolybdate-OSM and tetraphenylborate-OSM as electroactive materials [91]. The statistical overview of all the documented analytical estimations for the exploitation of OSM is presented in Fig. 2. It was revealed that hyphenated techniques (43%) are commonly used to analyze OSM in different samples.

Fig. 2
figure 2

The area chart displays the quantitative data relationship between the publication count and publication year [A] and sunburst chart revealed the percentage utility of analytical technique/methods for OSM [B]

Full size image

Sample treatment

Design a new selective and specific analytical protocol for quantifying the target analyte with excellent accuracy; choose the optimal IS significant step before the sample pretreatment begins.

The selection of an appropriate IS is of utmost importance. It should be chemically similar to the target assays being analyzed but not naturally present in a sample. The IS compensates for the loss of analyte at all stages of sample preparation and chromatographic analysis. Opting for compounds with the same physical and chemical properties as the target compounds is the most effective approach. In MS, a deuterated analog of the compound of interest is expected to be used.

An excellent example of this is the use of OSM-d3, OSM-C-d3, [2H5]-OSM, [13C,2H3]-OSM-C, OSM-d2, OSM-H2, OSM-C-d2, and OSM-C-H2 [27,28,29,30,31,32, 34, 36, 40,41,42,43,44, 49, 53]. However, apart from a deuterated analog or stable isotopes, in some cases, the compounds used as IS are drugs clinically explored to treat diseases are lidocaine hydrochloride, cephalexin, clopidogrel carboxylate [38, 39, 50]. Sample treatment is a significant part of the analysis protocol. Developing a suitable sample preparation procedure involves several steps, such as extraction and purification, to obtain a final concentrate of the target analyte extract that is as free of matrix compounds as possible [92]. The principle of green analytical chemistry emphasizes using direct analytical techniques to minimize the need for sample treatment [93]. The goal is to reduce the environmental, health, and safety issues of traditional sample preparation methods. However, direct analysis may only sometimes be feasible, as the sample needs to be in the appropriate state, and higher sensitivity, selectivity, or throughput may be required. Therefore, proper sample preparation is crucial when developing an analytical protocol for the OSM and OSM-C. The protocols have yet to report direct analysis of biological specimens for OSM. Sample preparation is necessary to make biological samples suitable for the selected protocol for quantifying the same. To achieve greater sensitivity, selectivity, or performance, biological specimens should be void of proteins, salts, sugars, and other essential compounds to minimize interference and matrix effects of early and late elution components [94].

8% trichloroAcOH, ACN, perchloric acid, and MeOH are the common precipitating agents followed by fast centrifugation to remove the proteins from biological specimens for PP [27, 29, 30, 34, 53].

Most reports use SPE, PP, and LLE as standard extraction techniques. Applying SPE sample preparation is a slightly new technique for PP and LLE. It is more often used for OSM by scientists and researchers from biological and environmental specimens [26, 28, 31, 32, 36,37,38,39,40,41,42,43,44, 51]. Off-line SPE with mixed phase cation (MPC)-standard density (SD) 96-well plate using MeOH: 50 mM AmAc (90:10 v/v) revealed a high % recovery with adequate elution of the analyte [31]. LC with strong cation exchangers separates and isolates acidified and basified sample extracts [36,37,38]. Most reports use various ratios of ammonia in MeOH to elute analytes from SPE cartridges. Since SPE and LLE pretreatment techniques are unsuitable for animal tissues, a simple and rapid QuEChERS sample preparation method was used in chicken muscle [33] due to the large sample consumption and time-consuming sample treatment procedures of SPE, PP, and LLE. Online in-tube solid-phase microextraction was reported to be a more efficient method for extracting analytes in environmental waters, reducing analysis time and providing better sensitivity and precision than the abovementioned procedures.

Recent updates for current pharmaceutical research aspects of OSM

In order to wrap up our review of the OSM, we made an effort to incorporate the latest updates for 2021. During our investigation using various reputable databases, we were surprised to find that pharmaceutical researchers have been focusing on exploring OSM in different areas due to the impact of the pandemic and other viral infections. These include repurposing, clinical approaches, medicinal chemistry, development of pharmaceutical formulations, pharmaceutical analysis, and the evaluation of pharmacokinetics and pharmacodynamics [95,96,97,98,99,100,101,102,103,104,105,106,107,108,109]. The details of the research scope, areas studied, and specific findings are outlined in Table 5. The exploration of the drug in clinical research has led to important discoveries regarding its potential use on its own or in combination with the effective treatment of COVID-19 and influenza patients. Medicinal chemistry research has been dedicated to developing new derivatives to combat resistant influenza.

Table 5 Recent scientific insights into pharmaceutical investigations of OSM
Full size table

Discussion and conclusion

The present roadmap thoroughly and comprehensively outlines the cumulative protocol for assessing OSM, whether used alone or with numerous other conventional antiviral candidates. OSM has been a consistent choice as a neuraminidase inhibitor for prophylaxis and managing infections caused by type A (pandemic H1N1) and B influenza viruses over the past two decades. M2 and neuraminidase inhibitors, two distinct therapeutic agents, are employed to combat influenza infections. However, given the resistance of H1N1 isolates to M2 inhibitors, neuraminidase inhibitors, with OSM leading the way, have emerged as the ideal approach. Therefore, our work provides a comprehensive and detailed analytical profile of OSM from 1999 – 2021, instilling confidence in its effectiveness. The author's research on OSM detection protocols highlights the effectiveness of hyphenated and chromatography techniques. These methods, including LC–MS/MS, UPLC–MS/MS, HPLC, HPTLC, UPLC, UV–Vis spectrophotometry, spectrofluorometry, FTIR, capillary electrophoresis, potentiometry, and voltammetry, have been extensively studied. Hyphenated techniques are the primary analytical technique reported in the literature review for OSM and OSM-C analysis in pharmaceutical and biological samples. These protocols demonstrate excellent specificity, reliable separation efficacy, a broad linearity range, and high automation.

Regarding detection sensitivity, the hyphenated protocols are more sensitive than the reported chromatographic protocols. Few documented reports highlighted OSM detection using LC–MS/MS in environmental water, surface water, sewage discharge, Neya River, treated sewage effluent, and surface water due to the emergence of OSM-resistant virus stains with the widespread use of TamifluTMcapsules. By surveying the reports 1999–2021, it is revealed that FA was the most common volatile additive used in solvent systems to improve the shape, resolution, and peak resolution of the OSM and, in the solvent system, dramatically decreased the interference by matrix effects. The most common ionization source is ESI; notwithstanding, ESI is the most widely employed ion source in the documented procedures. ACN is the major eluent in various reports in the solvent system, confirmed by LC–MS / MS and HPLC in 27 of 42 experiments, possibly due to its strong eluting power and favorable UV transmittance. To date, 13 analytical reports have been explored in the literature to determine OSM using HPLC.

Several reports have been published on the analysis of OSM using spectral protocols, which are rapid and easy to use. However, these protocols are less effective in analyzing OSM samples of biological origin due to interference from components and additives commonly found in pharmaceutical products. Electrochemical protocols, on the other hand, are cost-effective, rapid, and robust and can accurately detect the sample of interest, even in complex and impure samples. Despite their advantages, only a few studies have reported the detection of OSM using electrochemical protocols in pharmaceutical and biological samples, and there are few documented protocols for pharmacokinetics and bioequivalence studies. Based on the literature, many official impurities of OSM are known, opening up the possibility of comprehensive toxicity assessments (in vivo and in vitro) of OSM.

Also, impurity profiling of OSM and its active metabolites (OSM-C) has yet to be achieved. Furthermore, the reports have yet to be established according to the principles of green analytical chemistry to minimize the side effects associated with analytical procedures on the environment and analysts/operators. Regulatory authorities recommend implementing a life cycle management approach to develop analytical protocols that reduce the costs of an analytical report during its life cycle. In conclusion, all analytical protocols have specific benefits and drawbacks; a suitable protocol is selected based on the protocol's requirements to achieve the intended outcomes.

Availability of data and materials

All data and material available upon request.

Abbreviations

ACV:

Acyclovir

FA:

Formic acid

ACN:

Acetonitrile

AmAc:

Ammonium acetate

ESI:

Electrospray ionization

MeOH:

Methanol

H2O:

Water

AmFa:

Ammonium formate

aq:

Aqueous

EtOH:

Ethanol

AcOH:

Acetic acid

AmAc:

Ammonium acetate

BH:

Base hydrolysis

RT:

Room temperature

AH:

Acid hydrolysis

OD:

Oxidative degradation

TD:

Thermal degradation

NaOH:

Sodium hydroxide

LOD:

Limit of detection

LOQ:

Limit of quantitation

D0 :

Zero-order spectrophotometry

D1 :

First-order spectrophotometry

TCNQ:

7,7,8,8-Tetracyanoquinodimethane

Me2CO:

Acetone

RD:

Ratio difference spectrophotometry

\(\Delta\)A:

Difference spectrophotometry

KMnO4 :

Potassium permanganate

NaOH:

Sodium hydroxide

NBD-Cl:

4-Chloro-7-nitrobenzo-2-oxo-1,3-diazole

FEM:

Fluorescence emission

FET:

Fluorescence excitation

FLA:

Fluorescamine

FMA:

Formaldehyde

λem:

Emission

λex:

Excitation

NQS:

1,2-Naphthoquinone-4-sulfonic acid

NR:

Not reported

SPE:

Solid-phase extraction

PP:

Protein precipitation

OSM-d3:

Deuterated oseltamivir

OSM-C-d3:

Deuterated oseltamivir carboxylate

QuEChERS:

Quick, easy, cheap, effective, rugged and safe

AMT-d15 :

Amantadine-d15 hydrochloride

RBV13C5 :

Ribavirin-13C5

LLE:

Liquid-liquid extraction

LH:

Lidocaine hydrochloride

CE:

Cephalexin

CPC:

Clopidogrel carboxylate

NR:

Not reported

LC–MS/MS:

Liquid chromatography-tandem mass spectrometry

LC-MS:

Liquid chromatography-mass spectrophotometry

HPLC:

High-performance liquid chromatography

UHPLC:

Ultra-high-performance liquid chromatography

HPTLC:

High-performance thin-layer chromatography (HPTLC)

FTIR:

Fourier transform infrared spectrometry

References

  1. Widmer N, Meylan P, Ivanyuk A, Aouri M, Decosterd LA, Buclin T (2009) Oseltamivir in seasonal, avian H5N1 and pandemic 2009 A/H1N1 influenza. Clin Pharmacokinet 49:741–765. https://doi.org/10.2165/11534730-000000000-00000

    Article  Google Scholar 

  2. Elliott M (2001) Zanamivir: from drug design to the clinic. Philos Trans R Soc Lond B Biol Sci 356:1885–1893. https://doi.org/10.1098/rstb.2001.1021

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  3. Ruf BR, Szucs T (2009) Reducing the burden of influenza-associated complications with antiviral therapy. Infection 37:186–196. https://doi.org/10.1007/s15010-009-8241-1

    Article  CAS  PubMed  Google Scholar 

  4. Shtyrya YA, Mochalova LV, Bovin K (2009) NV Influenza virus neuraminidase: structure and function. Acta Naturae 1:26–32. https://doi.org/10.32607/20758251-2009-1-2-26-32

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  5. Varghese JN, Colman PM (1991) Three-dimensional structure of the neuraminidase of influenza virus A/Tokyo/3/67 at 2· 2 Å resolution. J Mol Biol 221:473–486. https://doi.org/10.1016/0022-2836(91)80068-6

    Article  CAS  PubMed  Google Scholar 

  6. Colman PM (1994) Influenza virus neuraminidase: structure, antibodies, and inhibitors. Protein Sci 3:1687–1696

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. Gubareva LV, Kaiser L, Hayden FG (2000) Influenza virus neuraminidase inhibitors. The Lancet 355:827–835. https://doi.org/10.1016/S0140-6736(99)11433-8

    Article  CAS  Google Scholar 

  8. Von Itzstein M, Wu W-Y, Kok GB, Pegg MS, Dyason JC, Jin B, Van Phan T, Smythe ML, White HF, Oliver SW (1993) Rational design of potent sialidase-based inhibitors of influenza virus replication. Nature 363:418–423. https://doi.org/10.1038/363418a0

    Article  Google Scholar 

  9. Tan Q, Duan L, Ma Y, Wu F, Huang Q, Mao K, Xiao W, Xia H, Zhang S, Zhou E (2020) is oseltamivir suitable for fighting against COVID-19: in silico assessment, in vitro and retrospective study. Bioorg Chem 104:104257. https://doi.org/10.1016/j.bioorg.2020.104257

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. Indian Pharmacopoeia (2018) Vol. I to IV, The Indian Pharmacopoeia Commission, Ghaziabad, Govt. of India, Ministry of Health & Family Welfare, New Delhi

  11. British Pharmacopoeia (2020) The British Pharmacopoeia Comission, London

  12. Ward P, Small I, Smith J, Suter P, Dutkowski R (2005) Oseltamivir (Tamiflu®) and its potential for use in the event of an influenza pandemic. J Antimicrob Chemother 55:i5–i21. https://doi.org/10.1093/jac/dki018

    Article  CAS  PubMed  Google Scholar 

  13. Babu YS, Chand P, Bantia S, Kotian P, Dehghani A, El-Kattan Y, Lin T-H, Hutchison TL, Elliott AJ, Parker CD (2000) BCX-1812 (RWJ-270201): discovery of a novel, highly potent, orally active, and selective influenza neuraminidase inhibitor through structure-based drug design. J Med Chem 43:3482–3486. https://doi.org/10.1021/jm0002679

    Article  CAS  PubMed  Google Scholar 

  14. Bianco A, Brufani M, Dri DA, Melchioni C, Filocamo L (2005) Design and synthesis of a new furanosicsialylmimetic as a potential influenza neuraminidase viral inhibitor. Lett Org Chem 2:83–88

    Article  CAS  Google Scholar 

  15. Hajzer V, Fišera R, Latika A, Durmis J, Kollár J, Frecer V, Miertuš Z, Tučeková S, Kostolanský F, Varečková E (2017) Stereoisomers of oseltamivir–synthesis, in silico prediction and biological evaluation. Org Biomol Chem 15:1828–1841. https://doi.org/10.1039/C6OB02673G

    Article  CAS  PubMed  Google Scholar 

  16. Sartori A, Dell’Amico L, Battistini L, Curti C, Rivara S, Pala D, Kerry PS, Pelosi G, Casiraghi G, Rassu G (2014) Synthesis, structure and inhibitory activity of a stereoisomer of oseltamivir carboxylate. Org Biomol Chem 12:1561–1569. https://doi.org/10.1039/C3OB42069H

    Article  CAS  PubMed  Google Scholar 

  17. Shibasaki M, Kanai M (2008) Synthetic strategies for oseltamivir phosphate. Eur J Org Chem 11:1839–1850. https://doi.org/10.1002/ejoc.200800033

    Article  CAS  Google Scholar 

  18. Bardsley A, Elliot A, Noble S (1999) Oseltamivir. Drugs 58:851–860. https://doi.org/10.2165/00003495-199958050-00007

    Article  Google Scholar 

  19. McClellan K, Perry CM (2001) Oseltamivir. Drugs 61:263–283. https://doi.org/10.2165/00003495-200161020-00011

    Article  CAS  PubMed  Google Scholar 

  20. Massarella JW, He GZ, Dorr A, Nieforth K, Ward P, Brown A (2000) The pharmacokinetics and tolerability of the oral neuraminidase inhibitor oseltamivir (Ro 64–0796/GS4104) in healthy adult and elderly volunteers. J Clin Pharmacol 40:836–843. https://doi.org/10.1177/00912700022009567

    Article  CAS  PubMed  Google Scholar 

  21. He G, Massarella J, Ward P (1999) Clinical pharmacokinetics of the prodrug oseltamivir and its active metabolite Ro 64–0802. Clin Pharmacokinet 37:471–484. https://doi.org/10.2165/00003088-199937060-00003

    Article  CAS  PubMed  Google Scholar 

  22. Eisenberg EJ, Bidgood A, Cundy KC (1997) Penetration of GS4071, a novel influenza neuraminidase inhibitor, into rat bronchoalveolar lining fluid following oral administration of the prodrug GS4104. Antimicrob Agents Chemother 41:1949–1952. https://doi.org/10.1128/AAC.41.9.1949

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Whitley RJ, Hayden FG, Reisinger KS, Young N, Dutkowski R, Ipe D, Mills RG, Ward P (2001) Oral oseltamivir treatment of influenza in children. J Pediatr Infect Dis 20:127–133

    Article  CAS  Google Scholar 

  24. Centre for Disease, Oseltamivir (Tamiflu), (2019)

  25. United State Pharmacopeia (2021) USP 44/ NF 39. US Pharmacopoeial Convention. Inc., New York

  26. Kanneti R, Bhavesh D, Paramar D, Bhatt PA (2011) Development and validation of a high-throughput and robust LC–MS/MS with electrospray ionization protocol for simultaneous quantitation of oseltamivir phosphate and its oseltamivir carboxylate metabolite in human plasma for pharmacokinetic studies. Biomed Chromatogr 25:727–733. https://doi.org/10.1002/bmc.1509

    Article  CAS  PubMed  Google Scholar 

  27. Hu ZY, Laizure SC, Meibohm B, HerringVL PRB (2013) Simple and sensitive assay for quantification of oseltamivir and its active metabolite oseltamivir carboxylate in human plasma using high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry: improved applicability to pharmacokinetic study. J Pharm Biomed Anal 72:245–250. https://doi.org/10.1016/j.jpba.2012.08.029

    Article  CAS  PubMed  Google Scholar 

  28. Gupta A, Guttikar S, Shrivastav PS, Sanyal M (2013) Simultaneous quantification of prodrug oseltamivir and its metabolite oseltamivir carboxylate in human plasma by LC–MS/MS to support a bioequivalence study. J Pharm Anal 3:149–160. https://doi.org/10.1016/j.jpha.2012.11.004

    Article  CAS  PubMed  Google Scholar 

  29. Kromdijk W, Rosing H, Van den Broek MPHJ, Beijnen JH, Huitema ADR (2012) Quantitative determination of oseltamivir and oseltamivir carboxylate in human fluoride EDTA plasma including the ex vivo stability using high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry. J Chromatogr B 891:57–63. https://doi.org/10.1016/j.jchromb.2012.02.026

    Article  CAS  Google Scholar 

  30. Heinig K, Bucheli F (2008) Sensitive determination of oseltamivir and oseltamivir carboxylate in plasma, urine, cerebrospinal fluid and brain by liquid chromatography–tandem mass spectrometry. J Chromatogr B 87:129–136. https://doi.org/10.1016/j.jchromb.2008.10.037

    Article  CAS  Google Scholar 

  31. Lindegårdh N, Hanpithakpong W, Wattanagoon Y, Singhasivanon P, White NJ, Day NPJ (2007) Development and validation of a liquid chromatographic–tandem mass spectrometric protocol for determination of oseltamivir and its metabolite oseltamivir carboxylate in plasma, saliva and urine. J Chromatogr B 859:74–83. https://doi.org/10.1016/j.jchromb.2007.09.018

    Article  CAS  Google Scholar 

  32. Wiltshire H, Wiltshire B, Citron A, Clarke T, Serpe C, Gray D, Herron W (2000) Development of a high-performance liquid chromatographic–mass spectrometric assay for the specific and sensitive quantification of Ro 64–0802, an anti-influenza drug, and its prodrug, oseltamivir, in human and animal plasma and urine. J Chromatogr B Biomed Sci Appl 745:373–388. https://doi.org/10.1016/S0378-4347(00)00300-5

    Article  CAS  PubMed  Google Scholar 

  33. Mu P, Xu N, Chai T, Jia Q, Yin Z, Qian S, Yang Y, Qiu J (2016) Simultaneous determination of 14 antiviral drugs and relevant metabolites in chicken muscle by UPLC–MS/MS after QuEChERS preparation. J Chromatogr B 1023:17–23. https://doi.org/10.1016/j.jchromb.2016.04.036

    Article  CAS  Google Scholar 

  34. Hooff GP, Meesters RJW, van Kampen JJA, van Huizen NA, Koch B, Al Hadithy AFY, van Gelder T, Osterhaus ADME, Gruters RA, Luider TM (2011) Dried blood spot UHPLC-MS/MS analysis of oseltamivir and oseltamivir carboxylate-a validated assay for the clinic. Anal Bioanal Chem 400:3473–3479. https://doi.org/10.1007/s00216-011-5050-z

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  35. Wu H, Wang J, Yang H, Li G, Zeng Y, Xia X, Li Z, Qian M (2017) Development and application of an in-cell cleanup pressurized liquid extraction with ultra-high-performance liquid chromatography-tandem mass spectrometry to detect prohibited antiviral agents sensitively in livestock and poultry feces. J Chromatogr A 1488:10–16. https://doi.org/10.1016/j.chroma.2017.01.070

    Article  CAS  PubMed  Google Scholar 

  36. Berendsen BJA, Wegh RS, Essers ML, Stolker AAM, S. Weigel S, (2012) Quantitative trace analysis of a broad range of antiviral drugs in poultry muscle using column-switch liquid chromatography coupled to tandem mass spectrometry. Anal Bioanal Chem 402:1611–1623. https://doi.org/10.1007/s00216-011-5581-3

    Article  CAS  PubMed  Google Scholar 

  37. Chan D, Tarbin J, Sharman M, Carson M, Smith M, Smith S (2011) Screening protocol for the analysis of antiviral drugs in poultry tissues using zwitterionic hydrophilic interaction liquid chromatography/tandem mass spectrometry. Anal Chim Acta 700:194–200. https://doi.org/10.1016/j.aca.2010.11.015

    Article  CAS  PubMed  Google Scholar 

  38. Lin CC, Yen JC, Wu YT, Lin LC, Tsai TH (2012) Chemical analysis and transplacental transfer of oseltamivir and oseltamivir carboxylic acid in pregnant rats. PLoS ONE 74:60–62. https://doi.org/10.1371/journal.pone.0046062

    Article  CAS  Google Scholar 

  39. Chang Q, Chow MSS, Zuo Z (2009) Studies on the influence of esterase inhibitor to the pharmacokinetic profiles of oseltamivir and oseltamivir carboxylate in rats using an improved LC/MS/MS protocol. Biomed Chromatogr 23:852–857. https://doi.org/10.1002/bmc.1195

    Article  CAS  PubMed  Google Scholar 

  40. Kataoka H, Shiba H, Saito K (2012) Automated analysis of oseltamivir and oseltamivir carboxylate in environmental waters by online in-tube solid-phase microextraction coupled with liquid chromatography-tandem mass spectrometry. Anal Protocols 4:1513–1518. https://doi.org/10.1039/C1AY05612C

    Article  CAS  Google Scholar 

  41. Kiguchi O, Ishii Y, Watanabe NT, Konno R, Matsubuchi A, T. Kobayashi T, (2020) Determination of oseltamivir phosphate and its metabolite with other pharmaceuticals in surface waters using solid phase extraction and isotope dilution liquid chromatography/tandem mass spectrometry. Int J Environ Anal Chem 100:346–360. https://doi.org/10.1080/03067319.2019.1637425

    Article  CAS  Google Scholar 

  42. Ghosh GC, Nakada N, Yamashita N, Tanaka H (2010) Oseltamivir carboxylate, the active metabolite of oseltamivir phosphate (tamiflu), detected in sewage discharge and river water in Japan. Environ Health Perspect 118:103–107. https://doi.org/10.1289/ehp.0900930

    Article  CAS  PubMed  Google Scholar 

  43. Takanami R, Ozaki H, Giri RR, Taniguchi S, Hayashi S (2010) Detection of antiviral drugs oseltamivir phosphate and oseltamivir carboxylate in Neya River, osaka, Japan. J Water Environ Technol 8:363–372. https://doi.org/10.2965/jwet.2010.363

    Article  Google Scholar 

  44. Khan GA, Lindberg R, Grabic R, Fick J (2012) The development and application of a system for simultaneously determining anti-infectives and nasal decongestants using online solid-phase extraction and liquid chromatography–tandem mass spectrometry. J Pharm Biomed Anal 66:24–32. https://doi.org/10.1016/j.jpba.2012.02.011

    Article  CAS  PubMed  Google Scholar 

  45. Bartels P, von Tümpling JW (2008) The environmental fate of the antiviral drug oseltamivir carboxylate in different waters. Sci Total Environ 405:215–225. https://doi.org/10.1016/j.scitotenv.2008.06.032

    Article  CAS  PubMed  Google Scholar 

  46. Straub JO (2009) An environmental risk assessment for oseltamivir (Tamiflu®) for sewage works and surface waters under seasonal-influenza-and pandemic-use conditions. Ecotoxicol Environ Saf 72:1625–1634. https://doi.org/10.1016/j.ecoenv.2008.09.011

    Article  CAS  PubMed  Google Scholar 

  47. Goncalves C, Perez S, Osorio V, Petrovic M, Alpendurada MF, Barcelo D (2011) Photofate of oseltamivir (tamiflu) and oseltamivir carboxylate under natural and simulated solar irradiation: kinetics, identification of the transformation products, and environmental occurrence. Environ Sci Technol 45:4307–4314. https://doi.org/10.1021/es1032629

    Article  CAS  PubMed  Google Scholar 

  48. Yamazaki Y, Ishii T, Honda A (2008) The influence of oseltamivir carboxylate and oseltamivir on hemagglutinin inhibition and microneutralization test. Antivir Res 80:354–359. https://doi.org/10.1016/j.antiviral.2008.07.008

    Article  CAS  PubMed  Google Scholar 

  49. Huang MF, Lin YR, Chang YT, Shiue YL, Liang SS (2018) Reductive amination assistance for quantification of oseltamivir phosphate and oseltamivir carboxylate by HPLC-MS/MS. J Chromatogr B 1087:23–28. https://doi.org/10.1016/j.jchromb.2018.03.040

    Article  CAS  Google Scholar 

  50. Yang D, Pearce RE, Wang X, Gaedigk R, Wan YJY, Yan B (2009) Human carboxylesterases HCE1 and HCE2: ontogenic expression, inter-individual variability and differential hydrolysis of oseltamivir, aspirin, deltamethrin and permethrin. Biochem Pharmacol 77:238–247. https://doi.org/10.1016/j.bcp.2008.10.005

    Article  CAS  PubMed  Google Scholar 

  51. Morimoto K, Kishimura K, Nagami T, Kodama N, Ogama Y, Yokoyama Y, Toda S, Chiyoda T, Shimada R, Inano A, Kano T (2011) Effect of milk on the pharmacokinetics of oseltamivir in healthy volunteers. J Pharm Sci 100:3854–3861. https://doi.org/10.1002/jps.22627

    Article  CAS  PubMed  Google Scholar 

  52. Yang YJ, Liu XW, Kong XJ, Qin Z, Jiao ZH, Li SH, Li JY (2018) Preparation and evaluation of oseltamivir molecularly imprinted polymer silica gel as liquid chromatography stationary phase. Mol 23:18–81. https://doi.org/10.3390/molecules23081881

    Article  CAS  Google Scholar 

  53. Loukotková L, Basavarajappa M, Lumen A, Roberts R, Mattison D, Morris SH, Fisher J, Beland FA, da Costa GG (2020) Pharmacokinetics of oseltamivir phosphate and oseltamivir carboxylate in non-pregnant and pregnant rhesus monkeys. Regul Toxicol Pharmacol 112:104–569. https://doi.org/10.1016/j.yrtph.2019.104569

    Article  CAS  Google Scholar 

  54. Pourghanbari G, Nili H, Moattari A, Mohammadi A, Iraji A (2016) Antiviral activity of the oseltamivir and melissa officinalis L. essential oil against avian influenza A virus (H9N2). VirusDisease 27:170–178. https://doi.org/10.1007/s13337-016-0321-0

    Article  PubMed  PubMed Central  Google Scholar 

  55. Joseph-Charles J, Geneste C, Laborde-Kummer E, Gheyouche R, Boudis H, Dubost JP (2007) Development and validation of a rapid HPLC protocol for the determination of oseltamivir phosphate in tamiflu® and generic versions. J Pharm Biomed Anal 44:1008–1013. https://doi.org/10.1016/j.jpba.2007.04.002

    Article  CAS  PubMed  Google Scholar 

  56. Green MD, Nettey H, Wirtz RA (2008) Determination of oseltamivir quality by colorimetric and liquid chromatographic protocols. Emerg Infect Dis 14:552. https://doi.org/10.3201/eid1404.061199

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  57. Chabai H, Ouarezki R, Guermouche S, Guermouche MH (2011) Rapid determination of oseltamivir phosphate in pharmaceutical preparation using monolithic silica HPLC column. J Liq Chromatogr Relat Technol 34:1913–1924. https://doi.org/10.1080/10826076.2011.582212

    Article  CAS  Google Scholar 

  58. Gungor S, Bulduk I, Sultan Aydın B, IlikciSagkan R (2021) A comparative study of HPLC and UV spectrophotometric protocols for oseltamivir quantification in pharmaceutical formulations. Acta Chromatogr. https://doi.org/10.1556/1326.2021.00925

    Article  Google Scholar 

  59. Lindegårdh N, Hien TT, Farrar J, Singhasivanon P, White NJ, Day NPJ (2006) A simple and rapid liquid chromatographic assay for evaluation of potentially counterfeit Tamiflu®. J Pharm Biomed Anal 42:430–433. https://doi.org/10.1016/j.jpba.2006.04.028

    Article  CAS  PubMed  Google Scholar 

  60. Aydoğmuş Z, Çağlar S, Toker S (2010) RP-HPLC protocol for determination of oseltamivir phosphate in capsules and spiked plasma. Anal Lett 43:2200–2209. https://doi.org/10.1080/00032711003698721

    Article  CAS  Google Scholar 

  61. Bahrami G, Mohammadi B, Kiani A (2008) Determination of oseltamivir carboxylic acid in human serum by solid phase extraction and high performance liquid chromatography with UV detection. J Chromatogr B 864:38–42. https://doi.org/10.1016/j.jchromb.2008.01.048

    Article  CAS  Google Scholar 

  62. Fuke C, Ihama Y, Miyazaki T (2008) Analysis of oseltamivir active metabolite, oseltamivir carboxylate, in biological materials by HPLC-UV in a case of death following ingestion of Tamiflu®. Legal Med 10:83–87. https://doi.org/10.1016/j.legalmed.2007.07.003

    Article  CAS  PubMed  Google Scholar 

  63. Suchada SJ, Jongrungruangchok BB, Songsak T (2011) Development and validation of oseltamivir carboxylate. Thai Pharmaceut Health Sci J 6:12–16

    Google Scholar 

  64. Ameti A, Slavkovska J, Starkoska K, Arsova-Sarafinovska Z (2012) A simple isocratic RP-HPLC protocol for quality control of oseltamivir capsules. Maced J Chem Chem Eng 31:205–215. https://doi.org/10.20450/mjcce.2012.10

    Article  CAS  Google Scholar 

  65. Bagary RI, El-Zaher AA, Morsy FA, Fouad MM (2014) Kinetic study of the alkaline degradation of oseltamivir phosphate and valacyclovir hydrochloride using validated stability indicating HPLC. Anal Chem Insights 9:41. https://doi.org/10.4137/ACI.S13878

    Article  PubMed  Google Scholar 

  66. Narasimhan B, Abida K, Srinivas K (2008) Stability indicating RP-HPLC protocol development and validation for oseltamivir API. Chem Pharm Bull 56:413–417. https://doi.org/10.1248/cpb.56.413

    Article  CAS  Google Scholar 

  67. Upmanyu N, Porwal PK (2019) Degradation behavior of oseltamivir phosphate under various stress conditions using stability-indicating HPLC protocol. J Pharm Sci Technol Manag 3:1–11

    Google Scholar 

  68. Albert K, Bockshorn J (2007) Chemical stability of oseltamivir in oral solutions. Pharmazie- Int J Pharm Sci 62:678–682. https://doi.org/10.1691/ph.2007.9.7106

    Article  CAS  Google Scholar 

  69. Rashed NS, Abdallah OM, Said NS (2017) Validated stability–indicating protocols for determination of oseltamivir phosphate. J Pharm Res Int, 1–9

  70. Khurana RK, Rao S, Beg S, Katare OP, Singh B (2016) Systematic development and validation of a thin-layer densitometric bioanalytical protocol for estimation of mangiferin employing analytical quality by design (AQbD) approach. J Chromatogr Sci 54:829–841. https://doi.org/10.1093/chromsci/bmw001

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  71. Youssef RM, Khamis EF, Younis SE, El-Yazbi FA (2013) Validated high-performance thin-layer chromatographic protocol for the evaluation of oseltamivir pharmaceutical formulations counterfeited with ascorbic acid compared with a colorimetric protocol. J Planar Chromatogr Mod TLC 26:427–434. https://doi.org/10.1556/JPC.26.2013.5.7

    Article  CAS  Google Scholar 

  72. Redasani VK, Patel PR, Marathe DY, Chaudhari SP, Shirkhedkar AA, Surana SJ (2018) A Review on derivative UV-spectrophotometry analysis of drugs in pharmaceutical formulations and biological samples review. J Chil Chem Soc 63:4126–4134. https://doi.org/10.4067/s0717-97072018000304126

    Article  CAS  Google Scholar 

  73. Ferhat S, AydoĞMuŞ Z (2008) A new spectrophotometric protocol for the determination of oseltamivir phospahate in bulk and capsules. J Fac Pharm Ist Unv 40:47–55

    Google Scholar 

  74. Gouthami TJ, Sivasubramanian L, Sowjanya V (2014) Development and validation of spectrophotometric protocols for the estimation of oseltamivir phosphate. Int J Pharm Res Technol 4:42–44

    Google Scholar 

  75. Youssef RM, El-Yazbi FA, Khamis EF, Younis SE (2014) Validated spectrophotometric protocols for the evaluation of oseltamivir counterfeit pharmaceutical capsules. Bull Fac Pharm Cairo Univ 52:63–69. https://doi.org/10.1016/j.bfopcu.2013.12.001

    Article  Google Scholar 

  76. Kumar JVS, Prasanthi S, Guravaiah M, Sekaran CB (2012) Application of potassium permanganate to the spectrophotometric determination of oseltamivir phosphate in bulk and capsules. Asian J Pharm Clin Res 5:18–22

    Google Scholar 

  77. Ramu BK, Babu MS, Prasad UV (2012) New spectrophotometric protocols development for the determination of oseltamivir phosphate in capsules based on the oxidation reactions of the olefenic double bond. Asian J Pharm Res Health Care 4:95–104

    Google Scholar 

  78. Ramu BK, Bab MS, Prasad UV (2013) A Novel visible spectrophotometric protocol development for the estimation of oseltamivir phosphate in capsules based on ferric hydroxamate reaction. Res J Pharm Dosage Forms Technol 5:70–74

    Google Scholar 

  79. Nebsen M, Fattah SAA, Hassan DW, Youssef NF (2011) Spectrophotometric and spectrofluorimetric determination of oseltamivir phosphate using 4-chloro-7-nitrobenzo-2-oxa 1, 3-diazole. Anal Chem Indian J 10:336–341

    CAS  Google Scholar 

  80. Aydoğmuş Z (2009) Simple and sensitive spectrofluorimetric protocol for the determination of oseltamivir phosphate in capsules through derivatization with fluorescamine. J Fluoresc 19:673–679. https://doi.org/10.1007/s10895-009-0461-3

    Article  CAS  PubMed  Google Scholar 

  81. Omar MA, Derayea SM, Mostafa IM (2015) Development and validation of a stability-indicating spectrofluorimetric protocol for the determination of H1N1 antiviral drug (oseltamivir phosphate) in human plasma through the Hantzsch reaction. RSC Adv 5:27735–27742. https://doi.org/10.1039/C4RA16650G

    Article  CAS  Google Scholar 

  82. Walash MI, Belal F, El-Enany N, El-Maghrabey MH (2012) Spectrofluorimetric determination of oseltamivir phosphate through derivatization with o-phthalaldehyde. Application to pharmaceutical preparations with a preliminary study on spiked plasma samples. Luminescence 27:511–518. https://doi.org/10.1002/bio.1385

    Article  CAS  PubMed  Google Scholar 

  83. Aboul-Enein Y, Bunaciu A, Sultana N, Fleschin S, Aydogmus Z (2012) A fourier transform infrared spectrophotometry protocol used for oseltamivir determination in pharmaceutical formulations. Gazi Univ J Sci 25:631–634

    Google Scholar 

  84. Tong AYC, Braund R, Tan EM, Tremblay LA, Stringer T, Trought K, Peake BM (2011) UV-induced photodegradation of oseltamivir (Tamiflu) in water. Environ Chem 8:182–189. https://doi.org/10.1071/EN10095

    Article  CAS  Google Scholar 

  85. Jabbaribar F, Mortazavi A, Jalali-Milani R, Jouyban A (2008) Analysis of oseltamivir in Tamiflu® capsules using micellar electrokinetic chromatography. Chem Pharm Bull 56:1639–1644. https://doi.org/10.1248/cpb.56.1639

    Article  CAS  Google Scholar 

  86. Laborde-Kummer E, Gaudin K, Joseph-Charles J, Gheyouche R, Boudis H, Dubost JP (2009) Development and validation of a rapid capillary electrophoresis protocol for the determination of oseltamivir phosphate in Tamiflu® and generic versions. J Pharm Biomed Anal 50:544–546. https://doi.org/10.1016/j.jpba.2009.05.016

    Article  CAS  PubMed  Google Scholar 

  87. Hamza SM, Rizk NMH, Matter HAB (2017) A new ion selective electrode protocol for determination of oseltamivir phosphate (Tamiflu) and its pharmaceutical applications. Arab J Chem 10:S236–S243. https://doi.org/10.1016/j.arabjc.2012.07.029

    Article  CAS  Google Scholar 

  88. Pop SF, Stefan-van Staden RI, van Staden JF, Aboul-Enein HY, Ion RM, Aydoğmuş Z (2012) Electroanalysis of oseltamivir phosphate using new microelectrodes based on zinc complexes with porphyrins and phthalocyanines. J Electrochem Soc 159:B789. https://doi.org/10.1149/2.001209jes

    Article  CAS  Google Scholar 

  89. Avramov Ivić M, Petrović SD, Mijin D, Drljević-Đurić KM (2011) The qualitative determination of oseltamivir phosphate in tamiflu® capsule by cyclic voltammetry. Hem Ind 65:87–91. https://doi.org/10.2298/HEMIND100908070A

    Article  Google Scholar 

  90. Hassan SSM, El-Nashar RM, El-Tantawy ASM (2013) A new validated potentiometric protocol for batch and continuous quality control monitoring of oseltamivir phosphate (taminil) in drug formulations and biological fluids. Electroanalysis 25:408–416. https://doi.org/10.1002/elan.201200437

    Article  CAS  Google Scholar 

  91. Jebali I, Belgaied JE (2014) A novel coated platinum electrode for oseltamivir determination in pharmaceuticals. Mater Sci Eng C 37:90–98. https://doi.org/10.1016/j.msec.2013.12.040

    Article  CAS  Google Scholar 

  92. Tadeo JL, Pérez RA, Albero B, García-Valcárcel AI, Sánchez-Brunete C (2012) Review of sample preparation techniques for the analysis of pesticide residues in soil. J AOAC Int 95:1258–1271. https://doi.org/10.5740/jaoacint.SGE_Tadeo

    Article  CAS  PubMed  Google Scholar 

  93. Płotka-Wasylka J (2018) A new tool for the evaluation of the analytical procedure: green analytical procedure index. Talanta 181:204–209. https://doi.org/10.1016/j.talanta.2018.01.013

    Article  CAS  PubMed  Google Scholar 

  94. Chang MS, Ji Q, Zhang J, El-Shourbagy TA (2007) Historical review of sample preparation for chromatographic bioanalysis: pros and cons. Drug Dev Res 68:107–133. https://doi.org/10.1002/ddr.20173

    Article  CAS  Google Scholar 

  95. Muralidharan N, Sakthivel R, Velmurugan D, Gromiha MM (2021) Computational studies of drug repurposing and synergism of lopinavir, oseltamivir and ritonavir binding with SARS-CoV-2 protease against COVID-19. J Biomol Struct Dyn 39:2673–2678. https://doi.org/10.1080/07391102.2020.1752802

    Article  CAS  PubMed  Google Scholar 

  96. Chiba S (2021) Effect of early oseltamivir on outpatients without hypoxia with suspected COVID-19. Wien Klin Wochenschr 133:292–297. https://doi.org/10.1007/s00508-020-01780-0

    Article  CAS  PubMed  Google Scholar 

  97. Park JH, Kim B, Antigua KJC, Jeong JH, Kim C, Choi WS, Oh S, Kim CH, Kim E-G, Choi YK (2021) Baloxavir-oseltamivir combination therapy inhibits the emergence of resistant substitutions in influenza A virus PA gene in a mouse model. Antivir Res 193:105–126. https://doi.org/10.1016/j.antiviral.2021.105126

    Article  CAS  Google Scholar 

  98. Sun L, Wang J, Shao L, Yuan C, Zhao H, Li D, Wang Z, Han P, Yu Y, Xu M (2021) Dexamethasone plus oseltamivir versus dexamethasone in treatment-naive primary immune thrombocytopenia: a multicentre, randomized, open-label, phase 2 trial. Lancet Haematol 8:e289–e298. https://doi.org/10.1016/S2352-3026(21)00030-2

    Article  CAS  PubMed  Google Scholar 

  99. Wang P, Oladejo BO, Li C, Fu L, Zhang S, Qi J, Lv X, Li X (2021) Structure-based design of 5′-substituted 1, 2, 3-triazolylated oseltamivir derivatives as potent influenza neuraminidase inhibitors. RSC Adv 11:9528–9541. https://doi.org/10.1039/D1RA00472G

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  100. Lee CW, TaiYL HLM, Chi H, Huang FY, Chiu NC, Huang CY, Tu YH, Wang JY, Huang DTN (2021) Efficacy of clarithromycin-naproxen-oseltamivir combination therapy versus oseltamivir alone in hospitalized pediatric influenza patients. J Microbiol Immunol Infect 54:876–884. https://doi.org/10.1016/j.jmii.2020.08.017

    Article  CAS  PubMed  Google Scholar 

  101. Mastroianni A, Vangeli V, Greco S, Urso F, Greco F, Chidichimo L, Mauro MV (2021) Oseltamivir and acute hepatitis, reality association or coincidence? Antivir Ther 26:87–92. https://doi.org/10.1177/13596535211041494

    Article  PubMed  Google Scholar 

  102. Zhao H, Jiang S, Ye Z, Zhu H, Hu B, Meng P, Hu Y, Zhang H, Wang K, Wang J (2021) Discovery of hydrazide-containing oseltamivir analogues as potent inhibitors of influenza A neuraminidase. Eur J Med Chem. https://doi.org/10.1016/j.ejmech.2021.113567

    Article  PubMed  PubMed Central  Google Scholar 

  103. Jayavarapu KR, Saranya Y, Divya M, Guptha RSK, Lakshmi TV, Satyanarayana T (2021) UV spectroscopic estimation of oseltamivir in bulk drug and formulation. World J Pharm Res 9:54–58

    CAS  Google Scholar 

  104. Gungor S, Bulduk I, Sultan Aydın B, Ilikci SR (2021) A comparative study of HPLC and UV spectrophotometric protocols for oseltamivir quantification in pharmaceutical formulations. Acta Chromatogr. https://doi.org/10.1556/1326.2021.00925

    Article  Google Scholar 

  105. Shimizu M, Fukami T, Ogawa H, Taniguchi T, Nomura Y, Nakajima M (2021) Systematic approach for screening of prodrugs: evaluation using oseltamivir analogues as models. J Pharm Sci 110:925–934. https://doi.org/10.1016/j.xphs.2020.10.018

    Article  CAS  PubMed  Google Scholar 

  106. Wiemken TL, Furmanek SP, Carrico RM, Peyrani P, Hoft D, Fry AM, Ramirez JA (2021) Effectiveness of oseltamivir treatment on clinical failure in hospitalized patients with lower respiratory tract infection. BMC Infect Dis 21:1–7. https://doi.org/10.1186/s12879-021-06812-2

    Article  Google Scholar 

  107. Tiwari VK, Powell DR, Broussy S, Berkowitz DB (2021) Rapid enantioselective and diastereoconvergent hybrid organic/biocatalytic entry into the oseltamivir core. J Org Chem 86:6494–6503. https://doi.org/10.1021/acs.joc.1c00326

    Article  CAS  PubMed  Google Scholar 

  108. Ye J, Lin L, Xu J, Chan PK, Yang X, Ma C (2021) Design, synthesis, biological evaluation and in silico studies of pyrazole-based NH2-acyl oseltamivir analogues as potent neuraminidase inhibitors. Pharmaceuticals 14:371. https://doi.org/10.3390/ph14040371

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  109. Ucar B, Acar T, Arayici PP, Derman S (2021) A nanotechnological approach in the current therapy of COVID-19: model drug oseltamivir-phosphate loaded PLGA nanoparticles targeted with spike protein binder peptide of SARS-CoV-2. Nanotechnology 32:485601. https://doi.org/10.1088/1361-6528/ac1c22

    Article  CAS  Google Scholar 

Download references

Acknowledgements

The authors are thankful to the Management of R. C. Patel Institute of Pharmaceutical Education and Research, Shirpur (MS), India, for providing essential library facilities to carry out this work.

Funding

Not applicable.

Author information

Authors and Affiliations

  1. Department of Pharmaceutical Chemistry, R. C. Patel Institute of Pharmaceutical Education and Research, Shirpur, 425405, MS, India

    Suraj R. Chaudhari, Vaibhavi K. Salunkhe, Shubham D. Tabade, Pragati K. Bhonde, Sarthak G. Kulkarni, Dnyaneshwar H. Maykar, Saurabh B. Ganorkar, Sanjay J,  Surana & Atul A. Shirkhedkar

Authors
  1. Suraj R. Chaudhari
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Vaibhavi K. Salunkhe
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Shubham D. Tabade
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Pragati K. Bhonde
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Sarthak G. Kulkarni
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Dnyaneshwar H. Maykar
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Saurabh B. Ganorkar
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Sanjay J
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Surana
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Atul A. Shirkhedkar
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

VKS, SDT, PKB, SGK, and DHM carried out the proposed review works, data collection, and validation work, and SRC and SBG organized the preliminary draft of the manuscript. AAS and SJS gave technical insights in compiling the final draft. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Suraj R. Chaudhari.

Ethics declarations

Competing interests

The authors declare that they have no competing interests.

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Chaudhari, S.R., Salunkhe, V.K., Tabade, S.D. et al. A critical analytical aspect on analytical protocols in the pharmaceutical analysis of H1N1 antiviral agent and its active metabolite. Futur J Pharm Sci 10, 110 (2024). https://doi.org/10.1186/s43094-024-00666-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s43094-024-00666-6

Keywords