Abstract

DESIGN AND DEVELOPMENT OF MICROBIALLY TRIGGERED ZIDOVUDINE TABLETS IN COLON CANCER

Surender Verma*, Dr. D. N. Mishra and Dr. Vipin Kumar

Abstract

The main objective of this study was to target zidovudine to the colon for improvement of exploited immunity by HIV infection using microbially triggered approach. Zidovudine is an antiretroviral drug which falls under the category of nucleoside reverse transcriptase inhibitor. Sodium starch glycolate (SSG) was also used for controlling drug release in such a manner that it can provide effective control over sustained release of drug. The matrix tablets were coated with enteric polymers as Eudragit L100 and Eudragit S100 in 1:1 ratio for controlling upto 12 hrs drug release in colon. The tablets were prepared by wet granulation method. Pre-formulation and micrometric studies of the drug, polymer & physical mixture were carried out. The results of pre-formulation studies were in accordance with reported literature values. Various in vitro tests like hardness, friability, weight variation, content uniformity, dissolution and disintegration were performed. Comparing the release profiles of formulations, under different pH conditions, influence of speed and concentration of super-disintegrant on the rate and extent of drug release was evident. It was also clear from the result that the drug release was faster in MF 22 but the effect of rat caecal content was more pronounced in case of MF 12. However MF 22 formulation batch has 96.45 % while MF12 formulation shows 94.02 % at stimulated intestinal pH. From the results of the data fitting to four different kinetic models, the best linearity was shown by zero order models giving value of r2 much closer to 1.. Value of “n” was found to lie between 0.67 - 0.87 indicating anomalous behavior (also called as nonfickian diffusion) as a mechanism of drug release. This consists of phenomenon of diffusion and erosion of polymer matrix.

Keywords: Microbially triggered, Guar gum, Xanthan gum, Eudragit S100, Eudragit L100.