Simultaneous HPTLC and RP-HPLC methods for determination of bumadizone in the presence of its alkaline-induced degradation product

Accurate, selective, sensitive and precise HPTLC‐densitometric and RP‐HPLC methods were developed and validated for determination of bumadizone calcium semi‐hydrate in the presence of its alkaline‐induced degradation product and in pharmaceutical formulation. Method A uses HPTLC‐densitometry, depending on separation and quantitation of bumadizone and its alkaline‐induced degradation product on TLC silica gel 60 F₂₅₄ plates, using hexane–ethyl acetate–glacial acetic acid (8:2:0.2, v/v/v) as a mobile phase followed by densitometric measurement of the bands at 240 nm. Method B comprises RP‐HPLC separation of bumadizone and its alkaline‐induced degradation product using a mobile phase consisting of methanol–water–acetonitrile (20:30:50, v/v/v) on a Phenomenex C₁₈ column at a flow‐rate of 2 mL/min and UV detection at 235 nm. The proposed methods were successfully applied to the analysis of bumadizone either in bulk powder or in pharmaceutical formulation without interference from other dosage form additives, and the results were statistically compared with the established method. Copyright © 2011 John Wiley & Sons, Ltd.     

Comparison of high performance TLC and HPLC for separation and quantification of chlorogenic acid in green coffee bean extracts

Two chromatographic methods, high-performance TLC (HPTLC) and HPLC, were developed and used for separation and quantitative determination of chlorogenic acid in green coffee bean extracts. For HPTLC silica gel Kieselgel 60 F 254 plates with ethyl acetate/dichlormethane/formic acid/acetic acid/water (100:25:10:10:11, v/v/v/v/v) as mobile phase were used. Densitometric determination of chlorogenic acid by HPTLC was performed at 330 nm. A gradient RP HPLC method was carried out at 330 nm. All necessary validation tests for both methods were developed for their comparison. There were no statistically significant differences between HPLC and HPTLC for quantitative determination of chlorogenic acid according to the test of equality of the means.     

Normal phase high performance liquid chromatography for determination of paclitaxel incorporated in a lipophilic polymer matrix

A normal phase (NP) high performance liquid chromatography (HPLC) method was developed for analysis of paclitaxel incorporated in poly(sebacic-co-ricinoleic acid), a lipophilic polymer matrix utilized for preparation of an injectable formulation for the localized delivery of paclitaxel. Thin layer chromatography experiments revealed that separation of paclitaxel from the polymer is dependent on the eluting strength (solvent strength) of the mobile phase. The HPLC system consists of a Purospher STRAR Si analytical HPLC column (5 microm, 250mm x 4mm, Merck), and 1-2.5% (v/v) methanol in dichloromethane as the mobile phase. Detection was by UV absorbance at 240 and 254 nm. The effect of the mobile phase composition on paclitaxel retention, peak shape and column efficiency, and the influence of the sample loading on the shape of the paclitaxel peak were studied. The mobile phases used for the chromatography consisted of 1.5% (v/v) methanol in dichloromethane. Paclitaxel was determined in the formulation and in the samples from degradation studies using UV detection at a wavelength of 254 nm. UV detection at 240 nm has advantages for following polymer matrix degradation products due to higher detector response at this wavelength. The utility of the proposed NP HPLC approach was demonstrated by assessment of intra- and inter-batch content uniformity, and by the determination of paclitaxel content after 7 and 60 days exposure of the paclitaxel-loaded polymer matrix to in vitro and in vivo degradation.     

Simultaneous estimation of pantoprazole and domperidone in pure powder and a pharmaceutical formulation by high-perfomance liquid chromatography and high-performance thin-layer chromatography methods

This paper describes validated high-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC) methods for the simultaneous estimation of pantoprazole (PANT) and domperidone (DOM) in pure powder and capsule formulations. The HPLC separation was achieved on a Phenomenex C18 column (250 mm id, 4.6 mm, 5 pm) using 0.01 M, 6.5 pH ammonium acetate buffer-methanol-acetonitrile (30 + 40 + 30, v/v/v, pH 7.20) as the mobile phase at a flow rate of 1.0 mL/min at ambient temperature. The HPTLC separation was achieved on an aluminum-backed layer of silica gel 60F254 using ethyl acetate-methanol (60 + 40, v/v) as the mobile phase. Quantification was achieved with ultraviolet (UV) detection at 287 nm over the concentration range 400-4000 and 300-3000 ng/mL with mean recovery of 99.35+/-0.80 and 99.08+/-0.57% for PANT and DOM, respectively (HPLC method). Quantification was achieved with UV detection at 287 nm over the concentration range 80-240 and 60-180 ng/spot with mean recovery of 98.40+/-0.67 and 98.75+/-0.71% for PANT and DOM, respectively (HPTLC method). These methods are simple, precise, and sensitive, and they are applicable for the simultaneous determination of PANT and DOM in pure powder and capsule formulations.     

Stability Indicating HPTLC and LC Determination of Dasatinib in Pharmaceutical Dosage Form

Two sensitive and reproducible methods are described for the quantitative determination of dasatinib in the presence of its degradation products. The first method was based on high performance thin layer chromatography (HPTLC) followed by densitometric measurements of their spots at 280 nm. The separation was on HPTLC aluminium sheets of silica gel 60 F₂₅₄ using toluene:chloroform (7.0:3.0, v/v). This system was found to give compact spots for dasatinib after development (R _F value of 0.23 ± 0.02). The second method was based on high performance liquid chromatography (HPLC) of the drug from its degradation products on reversed phase, PerfectSil column [C₁₈ (5 μm, 25 cm × 4.6 mm, i.d.)] at ambient temperature using mobile phase consisting of methanol:20 mM ammonium acetate with acetic acid (45:55, v/v) pH 3.0 and retention time (t _R = 8.23 ± 0.02 min). Both separation methods were validated as per the ICH guidelines. No chromatographic interference from the tablet excipients was found. Dasatinib was subjected to acid–alkali hydrolysis, oxidation, dry heat, wet heat and photo-degradation. The drug was susceptible to acid–alkali hydrolysis and oxidation. The drug was found to be stable in neutral, wet heat, dry heat and photo-degradation conditions. As the proposed analytical methods could effectively separate the drug from its degradation products, they can be employed as stability indicating.     

Simultaneous estimation of acetylsalicylic acid and clopidogrel bisulfate in pure powder and tablet formulations by high-performance column liquid chromatography and high-performance thin-layer chromatography

This paper describes validated high-performance column liquid chromatographic (HPLC) and high-performance thin-layer chromatographic (HPTLC) methods for simultaneous estimation of acetylsalicylic acid (ASA) and clopidogrel bisulfate (CLP) in pure powder and formulations. The HPLC separation was achieved on a Nucleosil C8 column (150 mm length x 4.6 mm id, 5 microm particle size) using acetonitrile-phosphate buffer, pH 3.0 (55 + 45, v/v) mobile phase at a flow rate of 1.0 mL/min at ambient temperature. The HPTLC separation was achieved on an aluminum-backed layer of silica gel 60F254 using ethyl acetate-methanol-toluene-glacial acetic acid (5.0 + 1.0 + 4.0 + 0.1, v/v/v/v) mobile phase. Quantitation was achieved with UV detection at 235 nm over the concentration range 4-24 microg/mL for both drugs, with mean recoveries of 99.98 +/- 0.28 and 100.16 +/- 0.66% for ASA and CLP, respectively, using the HPLC method. Quantitation was achieved with UV detection at 235 nm over the concentration range of 400-1400 ng/spot for both drugs, with mean recoveries of 99.93 +/- 0.55 and 100.21 +/- 0.83% for ASA and CLP, respectively, using the HPTLC method. These methods are simple, precise, and sensitive, and they are applicable for the simultaneous determination of ASA and CLP in pure powder and formulations.     

Chromatographic methods development,validation and degradation characterization of the antithyroid drug Carbimazole

The current paper reports the development and validation of stability‐indicating HPLC and HPTLC methods for the separation and quantification of main impurity and degradation product of Carbimazole. The structures of the degradation products formed under stress degradation conditions, including hydrolytic and oxidative, photolytic and thermal conditions, were characterized and confirmed by MS and IR analyses. Based on the characterization data, the obtained degradation product from hydrolytic conditions was found to be methimazole—impurity A of Carbimazole as reported by the British Pharmacopeia and the European Pharmacopeia. A stability‐indicating HPLC method was carried out using a Zorbax Eclipse Plus CN column (150 × 4.6 mm i.d, 5 μm particle size) and a mobile phase composed of acetonitrile–0.05 m KH₂PO₄ (20: 80, v/v) in isocratic elution, at a flow rate of 1 mL/min. The method was proved to be sensitive for the determination down to 0.5% of Carbimazole impurity A. Additionally, a stability‐indicating chromatographic HPTLC method was achieved using cyclohexane–ethanol (9:1, v/v) as a developing system on HPTLC plates F₂₅₄ with UV detection at 225 nm. The proposed HPLC and HPTLC methods were successfully applied to Carbimazole^® tablets with mean percentage recoveries of 100.12 and 99.73%, respectively.     

Stability indicating reversed-phase high-performance liquid chromatographic and thin layer densitometric methods for the determination of ziprasidone in bulk powder and in pharmaceutical formulations

Two sensitive and reproducible methods were developed and validated for the determination of ziprasidone (ZIP) in the presence of its degradation products in pure form and in pharmaceutical formulations. The fi rst method was based on reversed-phase high-performance liquid chromatography (HPLC), on a Lichrosorb RP C(18) column using water:acetonitrile:phosphoric acid (76:24:0.5 v/v/v) as the mobile phase at a fl ow rate of 1.5 mL min(-1) at ambient temperature. Quantification was achieved with UV detection at 229 nm over a concentration range of 10-500 micro g mL(-1) with mean percentage recovery of 99.71 +/- 0.55. The method retained its accuracy in presence of up to 90% of ZIP degradation products. The second method was based on TLC separation of ZIP from its degradation products followed by densitometric measurement of the intact drug spot at 247 nm. The separation was carried out on aluminium sheet of silica gel 60 F(254) using choloroform:methanol:glacial acetic acid (75:5:4.5 v/v/v) as the mobile phase, over a concentration range of 1-10 micro g per spot and mean percentage recovery of 99.26 +/- 0.39. Both methods were applied successfully to laboratory prepared mixtures and pharmaceutical capsules.     

Validated HPTLC and HPLC methods for determination of fluorometholone and sodium cromoglycate in presence of their impurities and degradation products; application to kinetic study and on rabbit aqueous humor

Fluorometholone (FLM) and Sodium Cromoglycate (CMG) are co-formulated in ophthalmic preparation and showed marked instability under different conditions. Two specific, sensitive and precise stability-indicating chromatographic methods have been developed and validated for their determination in the presence of their degradation products and FLM impurity. Ten components were efficiently separated by them. The first method was HPTLC-spectrodensitometry, where the separation was achieved using silica gel 60?F₂₅₄ HPTLC plates and developing system of ethyl acetate: methanol (9:1, v/v). The second method was a reversed phase HPLC associated with kinetic study of the degradation process and was successfully applied for determination of the studied compounds in spiked rabbit aqueous humor. The mobile phase was acetonitrile: methanol: 0.05?M potassium dihydrogenphosphate (0.1% trimethylamine); pH 2.5, adjusted with orthophosphoric acid (20: 30: 50, by volume). In both methods, the separated components were detected at 240?nm and system suitability was checked. Good correlation was obtained in the range of 0.10–24.00 and 0.20–48.00?µg band^?1, for FLM and CMG by HPTLC. While for HPLC, the linearity ranges from 0.01–50.00 and 0.05–50.00?µg?mL^?1 for both drugs. The methods were applied in pharmaceutical formulation, where they were compared to the reported method with no significant difference.     

Stability indicating methods for the determination of some anti-fungal agents using densitometric and RP-HPLC methods

Two chromatographic methods were developed for the determination of some anti-fungal drugs in the presence of either their degradation products or cortisone derivatives. The densitometric method determined mixtures of each of ketoconazole (KT), clotrimazole (CL), miconazole nitrate (MN) and econazole nitrate (EN) with the degradation products of each one. Mixtures of MN with hydrocortisone (HC) and of EN with triamcinolone acetonide (TA) were also successfully separated and determined by this technique. For KT and CL, a mixture of methanol:water:triethylamine (70:28:2 v/v) was used as a developing system and the spots were scanned at 243 nm and 220 nm for KT and CL, respectively. For MN and EN, a mixture of hexane:isopropyl alcohol:triethylamine (80:17:3 v/v) was used as a developing system and the spots were scanned at 225 nm for both drugs. The HPLC method determined mixtures of CL or EN with their degradation products which were separated and quantified on a Zorbax C8 column. Elution was carried out using methanol:phosphate buffer pH 2.5 (65:35 v/v) as a mobile phase at a flow rate of 1.5 ml/min and UV detection at 220 nm for CL. For EN, a mixture of methanol:water containing 0.06 ml triethylamine pH 10 (75:25 v/v) was used as a mobile phase at a flow rate of 1.5 ml/min and UV detection at 225 nm. The methods were also used to separate mixtures of CL with betamethasone dipropionate (BD) and EN with TA in a laboratory prepared mixture and in pharmaceutical preparations. The methods were sensitive, precise and applicable for determination of the drugs in pharmaceutical dosage forms.     

Estimation of Alprazolam and Sertraline in Pure Powder and Tablet Formulations by High-Performance Liquid Chromatography and High-Performance Thin-Layer Chromatography

Abstract

This article describes validated high-performance liquid chromatographic (HPLC) and high-performance thin-layer chromatographic (HPTLC) methods for simultaneous estimation of alprazolam (ALZ) and sertraline (SER) in pure powder and tablet formulation. The HPLC separation was achieved on a Nucleosil C18 column (150 mm long, 4.6 mm i.d., and 5-µm particle size) using acetonitrile and phosphate buffer (50 + 50 v/v), pH 5.5, as the mobile phase at a flow rate of 1.0 mL/min at ambient temperature. The HPTLC separation was achieved on an aluminum-backed layer of silica gel 60 F₂₅₄ using acetone/toluene/ammonia (6.0:3.0:1.0, v/v/v) as the mobile phase. Quantification with the HPLC method was achieved with ultraviolet (UV) detection at 230 nm over the concentration range 3–18 µg/mL for both drugs with mean recovery of 101.86 ± 0.21 and 100.57 ± 0.31% for ALZ and SER, respectively. Quantification in HPTLC was achieved with UV detection at 230 nm over the concentration range of 400–1400 ng/spot for both drugs with mean recoveries of 101.32 ± 0.15 and 100.38 ± 0.51% for ALZ and SER, respectively. These methods are rapid, simple, precise, sensitive, and are applicable for the simultaneous determination of ALZ and SER in pure powder and formulations.     

Simultaneous Determination of Tinidazole and Furazolidone in Suspension by HPTLC and HPLC

Abstract

High performance thin layer chromatographic (HPTLC) and high performance liquid chromatographic (HPLC) methods were developed for the simultaneous determination of Tinidazole and Furazolidone in suspension.

In the HPTLC method the separation of Tinidazole and Furazolidone was carried out on silica gel 60F₂₅₄ HPTLC glass plate using chloroform:methanol:ammonia (9:1:0.1 v/v) as a mobile phase. Rf values obtained were 0.63 and 0.79 for Furazolidone and Tinidazole respectively. Densitometric evaluation was done at 335 nm. Linearity was obtained within the concentration range 10–50 μg/ml and 3.5–17.5 μg/ml for Tinidazole and Furazolidone respectively.

The second method is based on high performance liquid chromatography on a reversed phase column (μ Bondapak C₁₈) using a mobile phase comprised of water: acetonitrile: triethylamine (80:20:0.1 v/v) adjusted to pH = 3.0 with dil. phosphoric acid. Retention times were 5.24 and 7.82 min for Tinidazole and Furazolidone respectively at a flow rate of 1.5 ml/min. Detection was done at 335 nm. Linearity was obtained within the concentration range 30–180 μg/ml and 10.5–63 μg/ml for Tinidazole and Furazolidone resp.     

Determination of rosuvastatin and ezetimibe in a combined tablet dosage form using high-performance column liquid chromatography and high-performance thin-layer chromatography

This paper describes validated HPLC and HPTLC methods for the simultaneous determination of rosuvastatin (ROS) and ezetimibe (EZE) in a combined tablet dosage form. The isocratic RP-HPLC analysis was performed on a Chromolith C18 column (100 x 6 mm id) using 0.1% (v/v) orthophosphoric acid solution (pH 3.5)-acetonitrile (63 + 37, v/v) mobile phase at a flow rate of 1 mL/min at ambient temperature. Quantification was carried out using a photodiode array UV detector at 245 nm over the concentration range of 0.5-10 microg/mL for ROS and EZE. The HPTLC separation was carried out on an aluminum-backed sheet of silica gel 60F(254) layers using n-butyl acetate-chloroform-glacial acetic acid (1 + 8 + 1, v/v/v) mobile phase. Quantification was achieved with UV densitometry at 245 nm over a concentration range of 0.1-0.9 micro/spot for ROS and EZE. The analytical methods were validated according to International Conference on Harmonization guidelines. Low RSD values indicated good precision. Both methods were successfully applied for the analysis of the drugs in laboratory-prepared mixtures and commercial tablets. No chromatographic interference from the tablet excipients was found. These methods are simple, precise, and sensitive, and are applicable for simultaneous determination of ROS and EZE in pure powder and tablets.     

Simultaneous determination of atorvastatin calcium and ramipril in capsule dosage forms by high-performance liquid chromatography and high-performance thin layer chromatography

Two simple and accurate methods to determine atorvastatin calcium and ramipril in capsule dosage forms were developed and validated using HPLC and HPTLC. The HPLC separation was achieved on a Phenomenex Luna C18 column (250 x 4.6 mm id, 5 microm) in the isocratic mode using 0.1% phosphoric acid-acetonitrile (38 + 62, v/v), pH 3.5 +/- 0.05, mobile phase at a flow rate of 1 ml/min. The retention times were 6.42 and 2.86 min for atorvastatin calcium and ramipril, respectively. Quantification was achieved with a photodiode array detector set at 210 nm over the concentration range of 0.5-5 microg/mL for each, with mean recoveries (at three concentration levels) of 100.06 +/- 0.49% and 99.95 +/- 0.63% RSD for atorvastatin calcium and ramipril, respectively. The HPTLC separation was achieved on silica gel 60 F254 HPTLC plates using methanol-benzene-glacial acetic acid (19.6 + 80.0 + 0.4, v/v/v) as the mobile phase. The Rf values were 0.40 and 0.20 for atorvastatin calcium and ramipril, respectively. Quantification was achieved with UV densitometry at 210 nm over the concentration range of 50-500 ng/spot for each, with mean recoveries (at three concentration levels) of 99.98 +/- 0.75% and 99.87 +/- 0.83% RSD for atorvastatin calcium and ramipril, respectively. Both methods were validated according to International Conference on Harmonization guidelines and found to be simple, specific, accurate, precise, and robust. The mean assay percentages for atorvastatin calcium and ramipril were 99.90 and 99.55% for HPLC and 99.91 and 99.47% for HPTLC, respectively. The methods were successfully applied for the determination of atorvastatin calcium and ramipril in capsule dosage forms without any interference from common excipients.     

Stability-indicating method for determination of oxyphenonium bromide and its degradation product by high-performance liquid chromatography

A high-performance liquid chromatographic (HPLC) method was developed for determination of oxyphenonium bromide (OX) and its degradation product. The method was based on the HPLC separation of OX from its degradation product, using a cyanopropyl column at ambient temperature with mobile phase of acetonitrile-25 mM potassium dihydrogen phosphate, pH 3.4 (50 + 50, v/v). UV detection at 222 nm was used for quantitation based on peak area. The method was applied to the determination of OX and its degradation product in tablets. The proposed method was also used to investigate the kinetics of the acidic and alkaline degradation of OX at different temperatures, and the apparent pseudo first-order rate constant, half-life, and activation energy were calculated. The pH-rate profile of the degradation of OX in Britton-Robinson buffer solutions within the pH range 2-12 was studied.     

HPLC, TLC, and first-derivative spectrophotometry stability-indicating methods for the determination of tropisetron in the presence of its acid degradates

Three stability-indicating assay methods were developed for the determination of tropisetron in a pharmaceutical dosage form in the presence of its degradation products. The proposed techniques are HPLC, TLC, and first-derivative spectrophotometry (1D). Acid degradation was carried out, and the degradation products were separated by TLC and identified by IR, NMR, and MS techniques. The HPLC method was based on determination of tropisetron in the presence of its acid-induced degradation product on an RP Nucleosil C18 column using methanol-water-acetonitrile-trimethylamine (65 + 20 + 15 + 0.2, v/v/v/v) mobile phase and UV detection at 285 nm. The TLC method was based on the separation of tropisetron and its acid-induced degradation products, followed by densitometric measurement of the intact spot at 285 nm. The separation was carried out on silica gel 60 F254 aluminum sheets using methanol-glacial acetic acid (22 + 3, v/v) mobile phase. The 1D method was based on the measurement of first-derivative amplitudes of tropisetron in H2O at the zero-crossing point of its acid-induced degradation product at 271.9 nm. Linearity, accuracy, and precision were found to be acceptable over concentration ranges of 40-240 microg/mL, 1-10 microg/spot, and 6-36 micro/mL for the HPLC, TLC, and 1D methods, respectively. The suggested methods were successfully applied for the determination of the drug in bulk powder, laboratory-prepared mixtures, and a commercial sample.     

Stability-Indicating Chromatographic Methods for Simultaneous Determination of Mosapride and Pantoprazole in Pharmaceutical Dosage Form and Plasma Samples

Simple, sensitive, selective, precise, and stability-indicating thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) methods for the determination of mosapride and pantoprazole in pharmaceutical tablets were developed and validated as per the International Conference on Harmonization guidelines. The TLC method employs aluminum TLC plates precoated with silica gel 60F₂₅₄ as the stationary phase and ethyl acetate/methanol/toluene (4:1:2, v/v/v) as the mobile phase to give compact spots for mosapride (R _f 0.73) and pantoprazole (R _f 0.45) separated from their degradation products; the chromatogram was scanned at 276 nm. The HPLC method utilizes a C18 column and a mobile phase consisting of acetonitrile/methanol/20 mM ammonium acetate (4:2:4, v/v/v) at a flow rate of 1.0 mL min⁻¹ for the separation of mosapride (t _R 11.4) and pantoprazole (t _R 4.4) from their degradation products. Quantitation was achieved with UV detection at 280 nm. The same HPLC method was successfully used in performing calibrations in lower concentration ranges for both drugs in human plasma using ezetimibe as internal standard. The methods were validated in terms of accuracy, precision, linearity, limits of detection, and limits of quantification. Mosapride and pantoprazole were exposed to acid hydrolysis and then analyzed by the proposed methods. As the methods could effectively separate the drugs from their degradation products, these techniques can be employed as stability-indicating methods that have been successively applied to pharmaceutical formulations without interference from the excipients. Moreover the HPLC method was successfully used in the determination of both drugs in spiked human plasma.

     

Stability-Indicating Chromatographic Methods for Simultaneous Determination of Mosapride and Pantoprazole in Pharmaceutical Dosage Form and Plasma Samples

Simple, sensitive, selective, precise, and stability-indicating thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) methods for the determination of mosapride and pantoprazole in pharmaceutical tablets were developed and validated as per the International Conference on Harmonization guidelines. The TLC method employs aluminum TLC plates precoated with silica gel 60F₂₅₄ as the stationary phase and ethyl acetate/methanol/toluene (4:1:2, v/v/v) as the mobile phase to give compact spots for mosapride (R _f 0.73) and pantoprazole (R _f 0.45) separated from their degradation products; the chromatogram was scanned at 276 nm. The HPLC method utilizes a C18 column and a mobile phase consisting of acetonitrile/methanol/20 mM ammonium acetate (4:2:4, v/v/v) at a flow rate of 1.0 mL min^?1 for the separation of mosapride (t _R 11.4) and pantoprazole (t _R 4.4) from their degradation products. Quantitation was achieved with UV detection at 280 nm. The same HPLC method was successfully used in performing calibrations in lower concentration ranges for both drugs in human plasma using ezetimibe as internal standard. The methods were validated in terms of accuracy, precision, linearity, limits of detection, and limits of quantification. Mosapride and pantoprazole were exposed to acid hydrolysis and then analyzed by the proposed methods. As the methods could effectively separate the drugs from their degradation products, these techniques can be employed as stability-indicating methods that have been successively applied to pharmaceutical formulations without interference from the excipients. Moreover the HPLC method was successfully used in the determination of both drugs in spiked human plasma.     

Quantitative determination of oxybutynin hydrochloride by spectrophotometry, chemometry and HPTLC in presence of its degradation product and additives in different pharmaceutical dosage forms

Simple, accurate, sensitive and validated UV spectrophotometric, chemometric and HPTLC-densitometric methods were developed for determination of oxybutynin hydrochloride (OX) in presence of its degradation product and additives in its pharmaceutical formulations. Method A is the first derivative of ratio spectra (DD¹) which allows the determination of OX in presence of its degradate in pure form and tablets by measuring the peaks amplitude at 216 nm. Method B and C are principal component regression (PCR) and partial least-squares (PLS) for determination of OX in presence of its degradate in pure form, tablets and syrup. While, the developed high performance thin layer chromatography HPTLC-densitometric method was based on the separation of OX from its degradation product, methylparaben and propylparaben followed by densitometric measurement at 220 nm which allows the determination of OX in pure form, tablets and syrup. The separation was achieved using HPTLC silica gel F₂₅₄ plates and chloroform:methanol:ammonia solution:triethylamine (100:3:0.5:0.2, v/v/v/v) as the developing system. The accuracy, precision and linearity ranges of the developed methods were determined. The results obtained were statistically compared with each other and to that of a reported HPLC method, and there was no significant difference between the proposed methods and the reported method regarding both accuracy and precision.     

Development and validation of HPTLC and green HPLC methods for determination of furosemide,spironolactone and canrenone,in pure forms,tablets and spiked human plasma

Two selective and accurate chromatographic methods are presented for simultaneous quantitation of spironolactone (SP) and furosemide (FR) and canrenone (CN), the main degradation product and the main active metabolite of SP. Method A was HPTLC, where separation was completed on silica gel HPTLC F₂₅₄ plates using ethyl acetate–triethylamine–acetic acid (9:0.7:0.5, by volume) as a developing system and UV detection at 254 nm. Method B was a green isocratic RP‐HPLC utilizing a C₁₈ (4.6 × 100 mm) column, the mobile phase consisting of ethanol–deionized water (45: 55, v/v) and UV estimation at 254 nm. Adjustment of flow rate at 1 mL/min and pH at 3.5 with glacial acetic acid was done. Regarding the greenness profile, the proposed RP‐HPLC method is greener than the reported one. ICH guidelines were followed to validate the developed methods. Successful applications of the developed methods were revealed by simultaneous determination of FR, SP and CN in pure forms and plasma samples in the ranges of 0.2–2, 0.05–2.6 and 0.05–2 μg/band for method A and 5–60, 2–60 and 2–60 μg/mL for method B for FR, SP and CN, respectively.