DEVELOPMENT AND EVALUATION OF A MUCOADHESIVE DRUG-DELIVERY SYSTEM FORDUAL-CONTROLLED DELIVERY OF NONOXYNOL-9

A mucoadhesive drug-delivery system (AmDDS) was developed using carbop ol 934P to achieve dual-controlled delivery of N-9 and EDTA for enhanc ed fertility control. The effects of mucoadhesive polymers and calcium -related interaction on the residence characteristics of AmDDS within the vagina and the release kinetic profile of N-9 from AmDDS were inve stigated. Maximum adhesion force and work of adhesion shear derived fr om mucin-polymer interaction between AmDDS and lamb vaginal mucosa inc reased with increasing the carbopol 934P loading in AmDDS. The maximum adhesion force of AmDDS to lamb vaginal mucosa decreased with increas ing pH of buffer in which polymer was dispersed. The mucoadhesive stre ngth of AmDDS to lamb vaginal mucosa increased with EDTA, but decrease d with calcium, indicating that divalent cations play an important rol e in mucus-carbopol adhesion. The amounts of N-9 released from AmDDS f ollowed a profile, which was similar to a Q vs. t(1/2) pattern. The op timal loading dose of N-9 in AmDDS to achieve appropriate release of N -9 was of the order of 1.0%. The release flux was not affected by EDTA , but was reduced in the presence of calcium chloride. These results i ndicate that AmDDS seems suitable to achieve controlled release of N-9 for prolonged spermicidal action and enhanced fertility control.