ABSTRACT
Rosuvastatin-Ca was prepared in solid dispersion as buccoadhesive tablets to increase its bioavailability and the release of the drug from its buccoadhesive formulae due to its poor aqueous solubility. The solid dispersions were prepared using β-cyclodextrin, polyethylene glycol 6000 and polyethylene glycol 4000 by kneading and solvent evaporation methods and were characterized by differential scanning calorimetry (DSC). They were also prepared using poloxamer 407 as a biocompatible and mucoadhesive carrier by freeze drying method. The buccoadhesive tablets of the drug were formulated using sodium carboxymethyl cellulose, hydroxypropylmethyl cellulose and sodium alginate by direct compression method. The prepared tablets were evaluated for their physical, dissolution, mucoadhesive and swelling properties. An in-vitro release study showed slow and prolonged release of the drug from tablets as compared to marketed formulation. Five formulae were selected for applying the recently reported analytical methods and results were compared statistically with a compendial one.
ABSTRACT
Three new accurate and sensitive methods were developed for the determination of two veterinary drugs. Florfenicol was analyzed by a stability-indicating TLC/densitometric method in presence of its amine degradation product obtained via acid hydrolysis. It was based on the difference in Rf values of the drug and its degradation product at 254 nm on silica gel 60 GF254 plates using chloroform–methanol (7:3 v/v) as developing solvent (Method A). However, buparvaquone was analyzed through reduction with NaBH4 in methanolto yielda red colored product measured spectrophotometrically at 489 nm (Method B). This reduction product was also measured spectrofluorometrically at 450 nm after excitation at 334 nm (Method C). Good linearity was obtained in the range of 10-100 μg/spot for florfenicol in method A and 10-120 or 0.3-2.4 μg mL-1 for buparvaquone by methods B and C with mean accuracy of 99.94%±0.89, 99.99%±0.99 or 99.66%±1.80, respectively. The densitometric method A proved to be stability-indicating in presence of 10-90% of buparvaquone amine degradation product. The three proposed methods were validated according to ICH guidelines and successfully applied for the assay of the cited drugs in their pharmaceutical formulations.
ABSTRACT
Aims: Stability indicating densitometry-TLC assay was established and validated for determination of azelastine hydrochloride (AZT) and emedastine difumarate (ETD) in the presence of their acid and oxidative degradants. Methodology: Forced degradation was performed using 30% H2O2 and 5 M HCl. The method was based on thin-layer chromatographic separation of the two drugs from their degradants, using methanol- 10% ammonia (9.5:0.5, v/v) as developing system, followed by densitometric measurements of the intact drug spots at 292 and 283 nm, for azelastine hydrochloride and emedastine difumarate respectively. Results: The linear range was 0.5 - 10.0 μg/spot, with mean recoveries of 100.09 ± 0.53% and 100.36 ± 0.40% for azelastine hydrochloride and emedastine difumarate respectively. Conclusion: The proposed method was successfully applied for the routine quality control analysis of both drugs in laboratory prepared mixtures and commercially available preparations. The degradation products were identified by IR and MS and the pathways were illustrated. The method was validated according to ICH.