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