Abstract:
In the formulation of clindamycin hydrochloride gel using carbopol 940, carbopol 94, poloxamer 407, hydroxyethyl cellulose and hydroxypropyl methylcellulose as gelling agents, the proper gelling agents were poloxamer 407, hydroxyethyl cellulose and hydroxypropyl methylcellulose in the concentration of 18, 2 and 3 percents by weight, respectively. All formulations were stable physically after passing Freez-Thaw condition. The chemical stability study at ambient temperature, Joel-Davis condition and Freez-Thaw condition showed that all formulations did not degrade significantly. Considering the diffusion coefficient as the release parameter, poloxamer 407 yielded the highest release rate whereas hydroxyethyl cellulose yielded the lowest. Being an aqueous (acetate buffer) or nonaqueous (chloroform) system, the receiving solutions did not effect the rank order of drug release from different formulations. A hydrophilic (Durapor(R)) a hydrophobic (Fluoropore(R)) and dialysis (Nylon 66) membranes also gave the same rank order of diffusion coefficients. In conclusion, any kinds of membranes and receiving solutions studied could be used for comparison of drug release if the release of drug from the preparations, not the diffusion through membrane, was the rate-limiting step.