Abstract
Zidovudine bioadhesive vaginal tablets were prepared using different polymer viz. Carbopol® 940, Carbopol® 934, Hydroxyl propyl methyl cellulose (HPMC) & guar gum by direct compression method. Compatibility of the drug and the polymers were assessed using Fourier transform infrared spectroscopy (FTIR). The bioadhesive strength measurement was performed by using mucosal membrane of goat vagina. The swelling behaviour of all the formulations was studied and the release mechanisms were explored in vitro by applying zero order, first order and Higuchi equations and finally in vivo study was done in female rabbit. Unchanged chemical integrity in all the formulation as indicated by FTIR studies revealed that no drug-polymer interaction occurred during the preparation and evaluation process. The swelling index differs with varied polymer concentrations and the in vitro drug release study with Carbopol® 934 (1:1) (BVT-7) showed uniform and prolonged drug release pattern over a period of 10 hrs. Time of peak concentration was achieved in 2 hrs for both oral and vaginal dosage forms with an AUC (po 6.509 µg hr mL-1; vaginally 8.406 µg hr mL-1) and Cmax (po 0.799 µg mL-1; vaginal 0.878 µg mL-1). Zidovudine with polymer Carbopol® 934 was successfully utilized in controlled delivery of the drug via vaginal route as bioadhesive tablet
