Authors:M. C. Damle, K. S. Topagi, and K. G. Bothara
An accurate, sensitive, rapid, and precise stability-indicating high-performance thin-layer chromatographic (HPTLC) method for analysis of nebivolol hydrochloride and hydrochlorothiazide as the bulk drug and in tablets has been developed and validated. Optimum separation was achieved on silica gel 60 F254 plates with ethyl acetate-methanol-acetic acid 6.5:1:0.5 (υ/υ) as mobile phase. Detection and quantification were performed at 280 and 270 nm for nebivolol hydrochloride and hydrochlorothiazide, respectively. The drugs get resolved with RF 0.46 ± 0.02 and 0.78 ± 0.02 for nebivolol hydrochloride and hydrochlorothiazide, respectively. The drugs were subjected to hydrolysis under acidic, basic, and neutral conditions, oxidation, heat, and photolysis as stress conditions. Peaks of degradation products were observed when the drugs were subjected to oxidative stress. Acidic conditions were also found to affect the tablet sample substantially. The degradation products resulting from stress conditions did not interfere with the drug peak. The method can be used for stability testing of these drugs during stability studies.
Authors:V. T. Gawande, K. G. Bothara, and C. O. Satija
Stability-indicating High-Performance Thin-Layer Chromatography (HPTLC) method for simultaneous estimation of cefixime trihydrate and azithromycin dihydrate was developed. Both the drugs were subjected to different stress conditions recommended by International Conference on Harmonization (ICH) guideline Q1A (R2). Forced degradation was carried out for hydrolytic, oxidative, photolytic, and thermal degradation conditions. Cefixime was susceptible for degradation under all stress conditions showing four degradation products (CI–IV). However, azithromycin formed only one degradation product (AI) under acid hydrolysis. Aluminum plates precoated with silica gel 60F254 were used as the stationary phase while mixture of ethyl acetate–methanol–acetone–toluene–ammonia (1:5:7:0.5:0.5, v/v) was used as mobile phase. Detection wavelength used was 235 nm for CEFI and CI–IV. AZI and AI were detected by post development derivatization, spraying with sulfuric acid–ethanol (1:4, v/v) followed by heating at 100 °C for 5 min. Degradation products were isolated by preparative HPTLC and characterized by MS/MS. The developed method was validated for linearity, precision, accuracy, specificity, and robustness and has been successfully applied in the analysis of these drugs in tablet dosage form.
Authors:M. R. Sengar, S. V. Gandhi, U. P. Patil, V. S. Rajmane, and K. G. Bothara
A simple, specific, accurate, and precise high-performance thin-layer chromatographic method for analysis of cefuroxime axetil and potassium clavulanate in a combined tablet dosage form is reported. The compounds were separated on aluminium foil plates precoated with silica gel 60 F254, with chloroform-methanol-toluene 4:3:3 (v/v) as mobile phase. Densitometric evaluation of the separated bands was performed at 225 nm. The two drugs were satisfactorily separated with RF 0.77 ± 0.0114 and 0.29 ± 0.0114 for cefuroxime axetil and potassium clavulanate, respectively. Response was a linear function of amount over the calibration ranges 500–2500 and 2000–10 000 ng per band, respectively. The method was successfully validated and used for analysis of the drugs in a pharmaceutical formulation. Recovery was 100.05 ± 0.98% for cefuroxime axetil and 99.94 ± 0.538% for potassium clavulanate (mean ± RSD).