Intrinsic dissolution testing: A tool for determining the effect of processing on dissolution behavior of the drug

Abstract

Intrinsic dissolution testing has been applied for characterization of pure API with respect to its dissolution behavior. The effect of formulation factors and processing parameters on dissolution rate is evaluated by dissolution testing of the final product, which is a time and resource-consuming process. Our objective was to use intrinsic dissolution testing for determining the effect of processing parameters on drug release. In the present study, an intrinsic dissolution testing method was developed for atenolol and validated according to the standard guidelines using USP-recommended dissolution media. Various experimental variables (compaction pressure and rotation speed of the disk) were optimized by studying at three levels. Atenolol was subjected to granulation in a super mixer granulator by applying standard wet granulation protocols. Granulation time and binder concentration were taken as process variables while dissolution rate was a response variable. Dissolution media had no interference with sample analysis, and all validation parameters for the developed method were in an acceptable range (%RSD > 1). The intrinsic dissolution rate of atenolol (1.84 ± 0.13 mg/cm2 min) was high due to its better solubility in dissolution media. The dissolution rate of atenolol was decreased by granulating with PVP under different conditions. We concluded that intrinsic dissolution testing method can be applied for determining the effect of processing parameters on dissolution rate of the API at the pre-compression level. This method will reduce experimentation for optimization of dissolution rate and will spare time and resources.