Dear Aditya,

I had not come across any literature speaking of the drug release rate in accordance with the HPMS content. However, to discuss this, we need to know the external matrix content used for release. Also the solubility of the drug plays a vital role in release. If your drug is hydrophobic and the external matrix is mere PBS solution, then you ought to add surfactant to the external matrix so that the drug would actually diffuse through the barrier. Also, if you are using UV spec for studying the rate, make sure the you homogenize/monodisperse the solution before analysis.

Cheers