An ultraviolet-spectrophotometric method for the determination of glimepiride in solid dosage forms.

BACKGROUND: Considering the cost of acquiring a liquid chromatographic instrument in underdeveloped economies, the rising incidence of diabetes mellitus, the need to evaluate the quality performance of glimepiride generics, and the need for less toxic processes, this research is an imperative. METHODS: The method was validated for linearity, recovery accuracy, intra- and inter-day precision, specificity in the presence of excipients, and inter-day stability under laboratory conditions. Student's t test at the 95% confidence limit was used for statistics. RESULTS: Using 96% ethanol as solvent, a less toxic and cost-effective spectrophotometric method for the determination of glimepiride in solid dosage forms was developed and validated. The results of the validated parameters showed a λ(max) of 231 nm, linearity range of 0.5-22 µg/mL, precision with relative SD of <1.0%, recovery accuracy of 100.8%, regression equation of y = 45.741x + 0.0202, R(2) = 0.999, limit of detection of 0.35 µg/mL, and negligible interference from common excipients and colorants. The method was found to be accurate at the 95% confidence limit compared with the standard liquid chromatographic method with comparable reproducibility when used to assay the formulated products Amaryl(®) (sanofi-aventis, Paris, France) and Mepyril(®) (May & Baker Nigeria PLC, Ikeja, Nigeria). The results obtained for the validated parameters were within allowable limits. CONCLUSION: This method is recommended for routine quality control analysis.

Antinociceptive and anti-inflammatory activities of crude extracts of Ipomoea involucrata leaves in mice and rats

OBJECTIVE@#To investigate antinociceptive and anti-inflammatory activities of crude extract from Ipomoea involucrata leaves (Convolvulaceae) in mice and rats.@*METHODS@#The antinociceptive activity was tested using acetic acid-induced abdominal writhing test in mice. The anti-inflammatory activity was evaluated using egg albumin induced oedema of rat paw.@*RESULTS@#Phytochemical screening showed the presence of alkaloids, flavonoids, saponins, terpenoids and tannin. At the doses of 25-100 mg/kg, Ipomoea involucrata exhibited dose-dependent and significant increase in pain threshold in acetic acid -induced writhing test of mice (P<0.05, student t-test) The administration of Ipomoea involucrata leaf extract (25-100 mg/kg) showed dose-dependent decreases in paw volume of egg albumin induced oedema in rats and a significant higher anti-inflammatory activity compared to the standard control (Aspirin).@*CONCLUSIONS@#These results support the claims on the traditional use of the of Ipomoea involucrata leaves in the treatment of toothache, rheumatic pains and other inflammatory conditions. Studies on the isolation and structural elucidation of the active principle are still needed being carried out.

Biodegradable microspheres based on gelatin-porcine mucin admixtures: in vitro and in vivo delivery studies.

Soluble mucus glycoprotein (S-mucin) processed from the small intestines (ileal region) of freshly slaughtered pigs via homogenization, dialysis, centrifugation and lyophilization and their admixtures with type B gelatin were used to prepare cefaclor-loaded microspheres by the emulsification-crosslinking method. The microspheres were evaluated for the in vitro delivery of cefaclor in both simulated intestinal fluid (SIF) without pancreatin (pH 7.4) and simulated gastric fluid (SGF) without pepsin (pH 1.2). Results obtained indicated that the microspheres formulated were highly mucoadhesive and that release of cefaclor in both release media was non-Fickian and was much higher and more rapid in SGF than in SIF and from microspheres based on gelatin alone when compared to those based on gelatin-procine mucin admixtures. The mean area under the plasma level versus time curves (AUC) was shown to be dependent on the formulation with values of 172.3 mug.h/ml for the control, 278.5 mug.h/ml for microspheres based on gelatin only and 353.0 mug.h/ml for microspheres formulated with equal parts of gelatin and mucin indicating that the rectal route may provide a therapeutically viable alternative to the oral route for the delivery of cefaclor. Further indications also emerged of a possibility of site-specific delivery of cefaclor to the small intestine through a careful selection of gelatin type and porcine mucin admixtures prior to formulation of the microspheres. On the whole, the inclusion of S-mucin in the composition of the microspheres had an enhancer effect on the release and rectal bioavailability of cefaclor which may be exploited in the design of a rectal delivery system of the drug.