Skip to main content

Table 1 Examples for applications of ultraviolet spectrophotometric methods for the determination of the minor component presented in different fixed-dose pharmaceutical combinations

From: Ultraviolet spectrophotometric methods for the determination of the minor component presented in fixed-dose pharmaceutical combinations through the last two decades (2000–2020)

Method Mixture Pharmaceutical combination Ref
Methods based on signal enhancing
 Zero-crossing derivative Chlorpheniramine maleate (CP), phenylephrine HCl (PE) and phenylpropanolamine HCl (PP) Tablet dosage form, labeled to contain (CP, 2 mg; PE, 5 mg, and PP, 20 mg) per one tablet [7]
Omeprazole (OMP), tinidazole (TIN), and doxycycline (DOX) Capsules dosage form, labeled to contain 20 mg (OMP), 500 mg (TIN), 50 mg (DOX) per one capsule [8]
 Area under the curve correction Ofloxacin (OFX), prednisolone acetate (PA) and tetryzoline HCl (TZH) with benzalkonium chloride (BNZ). Eye drops, labeled to contain 3 mg of OFX, 2 mg of PA, 0.4 mg of TZH, and 0.05 mg of BNZ per 1 mL [9]
Chemometric methods
 Continuous wavelet transform as a pre-processing tool in partial least-squares Drotaverine (DRO), caffeine (CAF), paracetamol (PAR), and p-aminophenol (PAP, the major impurity of PAR) Tablet dosage form, labeled to contain 40.0 mg of DRO, 400.0 mg of PAR, and 60.0 mg of CAF per one tablet [10]
 Partial least-squares Bromhexine (BRM) and cotrimoxazole Tablets dosage form labeled to contain cotrimoxazole and BRM per one tablet in ratio of (100:1) (in weight) [11]
Sulfamethoxazole (SMX) and trimethoprim (TMP) Oral suspension dosage form, labeled to contain 400 mg SMX, and 80 mg TMP per 5 mL in ratio (5:1) [12]
 Partial least squares with regression model updating Chloramphenicol (CPL) and dexamethasone sodium phosphate (DSP) with benzalkonium chloride (BNZ) Eye drops, labeled to contain 5 mg CPL, 1 mg DSP, and 0.1 mg BNZ per 1 mL [13]
 Artificial neural networks (ANN) Paracetamol (PAR) and orphenadrine citrate (ORN) Tablet dosage form, labeled to contain PAR, and ORN in ratio (14:1) per one tablet [14]
Methods based on geometrical relationship of standard addition
 H-Point standard addition Paracetamol (PAR) and diclofenac sodium (DCL) Tablet dosage form, labeled to contain (PAR 250 mg + DCL 50 mg) per one tablet in ratio (5:1) [15]
 Ratio H-point standard addition Tetryzoline HCl (TZH) with ofloxacin (OFX) and prednisolone acetate (PA) with benzalkonium chloride (BNZ) Eye drops, labeled to contain 3 mg of OFX, 2 mg of PA, 0.4 mg of TZH, and 0.05 mg of BNZ per 1 mL in ratio of (7.5:5:1) [16]
Metoclopramide hydrochloride (MET) with aspirin (ASP) Sachets
Each sachet contains10 mg MET, 1620 mg lysine acetylsalicylate (which was equivalent to 900 mg ASP), and aspartame in ratio of (1:90)
[17]
Sodium Cromoglicate (SCG)
Tetryzoline HCl (TZH) with benzalkonium chloride (BNZ)
Eye drops, labeled to contain 40 mg of SCG, 0.5 mg of TZH, and 0.1 mg of BNZ per 1 mL in ratio (80:1) [16]
 -Geometrical amplitude modulation
 -Geometrical induced amplitude modulation
Tetryzoline HCl (TZH) with ofloxacin (OFX) and prednisolone acetate (PA) with benzalkonium chloride (BNZ) Eye drops, labeled to contain 3 mg of OFX, 2 mg of PA, 0.4 mg of TZH, and 0.05 mg of BNZ per 1 mL [16]
Sodium cromoglicate (SCG)
Tetryzoline HCl (TZH) with benzalkonium chloride (BNZ)
Eye drops, labeled to contain 40 mg of SCG, 0.5 mg of TZH, and 0.1 mg of BNZ per 1 mL [16]
Methods based on geometrical relationship of blank subtraction
 Derivative compensation ratio Sodium cromoglicate (SCG) and xylometazoline hydrochloride (XYLO) Nasal drop, labeled to contain 2% SCG and 0.025% XYLO per 100 mL [18]
 Compensated area under the curve Tetryzoline HCl (TZH) with Ofloxacin (OFX) and prednisolone acetate (PA) with benzalkonium chloride (BNZ) Eye drops, labeled to contain 3 mg of OFX, 2 mg of PA, 0.4 mg of TZH, and 0.05 mg of BNZ per 1 mL [9]
Methods based on ratio spectra
 Ratio difference Pseudoephedrine hydrochloride (PSE) and ibuprofen (IBU) Tablet dosage form, labeled to contain 30 mg of (PSE), and 200 mg of (IBU) per one tablet [19]
Sodium cromoglicate (SCG) and fluorometholone (FLU) Ophthalmic solution, labeled to contain, SCG and FLU in ratio of (20:1) per 1 mL. [20]
Chloramphenicol (CPL) and dexamethasone sodium phosphate (DSP) with benzalkonium chloride (BNZ) Eye drops, labeled to contain 5 mg CPL, 1 mg DSP, and 0.1 mg BNZ per 1 mL [13]
 Ratio subtraction coupled with extended ratio subtraction Sodium cromoglicate (SCG) and fluorometholone (FLU) Eye drops, labeled to contain 20 mg of SCG and 1 mg of FLU per 1 mL [21]
 Ratio subtraction Ciprofloxacin (CIP) and fluocinolone acetonide (FLU Single-dose otic solution labeled to contain CIP and FLU in a ratio of (CIP: FLU) (12 : 1) per 1 mL [22]
Omeprazole (OMP), tinidazole (TIN), and doxycycline (DOX) Capsule dosage form, labeled to contain 20 mg (OMP), 500 mg (TIN), 50 mg (DOX) per one capsule [8]
Flumethasone (FP) pivalate and clioquinol (CL) Ear drops labeled to contain 0.2 mg of FP and 10 mg of CL per 1 mL [23]
 Extended ratio subtraction Ciprofloxacin (CIP) and fluocinolone acetonide (FLU Single-dose otic solution labeled to contain CIP and FLU in a ratio of (CIP: FLU) (12 : 1) per 1 mL. [22]
 Derivative ratio Pseudoephedrine sulphate (PSE), loratadine (LOR), and paracetamol (PAR). Tablet dosage form claimed to contain 120 mg of PSE, 5 mg of LOR, and 500 mg of PAR per one tablet [24]
 -Double divisor ratio spectra
 -Derivative
 -Area under curve of derivative ratio
 -Successive
 -Derivative of ratio spectra
Ofloxacin (OFX), prednisolone acetate (PA), and tetryzoline HCl (TZH) with benzalkonium chloride (BNZ) Eye drops, labeled to contain 3 mg of OFX, 2 mg of PA, 0.4 mg of TZH, and 0.05 mg of BNZ per 1 mL [9]
 Derivative ratio–zero crossing Omeprazole (OMP), tinidazole (TIN), and doxycycline (DOX Capsule dosage form, labeled to contain 20 mg (OMP), 500 mg (TIN), 50 mg (DOX) per one capsule [8]
 Successive derivative ratio Omeprazole (OMP), tinidazole (TIN), and doxycycline (DOX), Capsule dosage form, labeled to contain 20 mg (OMP), 500 mg (TIN), 50 mg (DOX) per one capsule [8]
ofloxacin (OFX), prednisolone acetate (PA), and tetryzoline HCl (TZH) with benzalkonium chloride (BNZ) Eye drops, labeled to contain 3 mg of OFX, 2 mg of PA, 0.4 mg of TZH, and 0.05 mg of BNZ per 1 mL [9]
 Constant center Pseudoephedrine sulphate (PSE), loratadine (LOR), and paracetamol (PAR). Tablet dosage form, labeled to contain 120 mg of PSE, 5 mg of LOR, and 500 mg of PAR per one tablet [24]
Omeprazole (OMP), tinidazole (TIN), and doxycycline (DOX) Capsule dosage form, labeled to contain 20 mg (OMP)/500 mg (TIN)/50 mg (DOX) per one capsule [8]
Sodium cromoglicate (SCG) and fluorometholone (FLU) Eye drops, labeled to contain 20 mg of SCG and 1 mg of FLU per 1 mL [21]
 Amplitude modulation Ciprofloxacin (CIP) and fluocinolone acetonide (FLU) Single-dose otic solution labeled to contain CIP and FLU in a ratio of (CIP: FLU) (12 : 1) per 1 mL [25]
Chloramphenicol (CHL), dexamethasone sodium phosphate (DXM), and tetryzoline hydrochloride (TZH) with benzalkonium chloride (BNZ) Eye drops, labeled to contain 5 mg of CHL, 1 mg of DXM, 0.25 mg of TZH, and 0.02 mg BNZ per 5 mL [13]
 -Amplitude summation
 -Absorption subtraction
Chloramphenicol (CHL), dexamethasone sodium phosphate (DXM), and tetryzoline hydrochloride (TZH) with benzalkonium chloride (BNZ) Eye drops, labeled to contain 5 mg of CHL, 1 mg of DXM, 0.25 mg of TZH, and 0.02 mg BNZ per 5 mL [13]
 -Absorptivity centering
 -Extended ratio subtraction
Ciprofloxacin (CIP) and fluocinolone acetonide (FLU) Single-dose otic solution labeled to contain CIP and FLU in a ratio of (CIP: FLU) (12 : 1) per 1 mL [22]
 Derivative subtraction coupled with constant multiplication Chloramphenicol (CPL) and dexamethasone sodium phosphate (DSP) with benzalkonium chloride (BNZ) Eye drops, labeled to contain 5 mg CPL, 1 mg DSP, and 0.1 mg BNZ per 1 mL [13]
 Mean centering Flumethasone pivalate (FP) and clioquinol (CL) Ear drops labeled to contain FP and CL in ratio of (1:50) (FP: CL) per 1 mL [23]
 Continuous wavelet transform Ofloxacin (OFX), prednisolone acetate (PA), and tetryzoline HCl (TZH) with benzalkonium chloride (BNZ) Eye drops, labeled to contain 3 mg of OFX, 2 mg of PA, 0.4 mg of TZH, and 0.05 mg of BNZ per 1 mL [16]
Drotaverine (DRO), caffeine (CAF), paracetamol (PAR), and p-aminophenol (PAP, the major impurity of PAR) Tablet dosage form, labeled to contain 40.0 mg of DRO, 400.0 mg of PAR, and 60.0 mg of CAF per one tablet [9]
Method based on spectrum addition and methods based on sample enrichment by spiking or spectrum addition technique
 Spectrum addition Ciprofloxacin (CIP) and fluocinolone acetonide (FLU) Single-dose otic solution labeled to contain CIP and FLU in a ratio of (CIP: FLU) (12 : 1) per 1 mL. [22]
 Sample spiking Sodium cromoglicate (SCG) and xylometazoline hydrochloride (XYLO) Nasal drop, labeled to contain 2% SCG and 0.025% XYLO per 100 mL [18]
Canagliflozin (CAG) and metformin (MEF) Tablet dosage form, labeled to contain10 mg (CAG) and 100 mg (MEF) [26]