Diltiazem.

The purpose of this study was selection of most influential variable for the preparation of prolonged release nanoparticulate formulation by desolvation method for diltiazem hydrochloride with bioadhesive polymer gelatin. Formulation and processing variables which effect various response variables were studied by a Taguchi design. Independent variables studied were the amount of polymer, amount of glutaraldehyde, amount of Poloxamer 237, acetone addition rate, pH, stirring time and stirring speed. The dependent variables considered were the particle size, polydispersity index, amount of drug released in 6 h, time required to release 60 % of drug, mucoadhesiveness, entrapment efficiency and loading efficiency. Pareto charts showed that the two significant factors affecting the response variables were amount of glutaraldehyde and amount of polymer.