Milad Jafari-Nodoushan - Science Department, Iran Polymer and Petrochemical Institute, Tehran, Iran.
Tannaz Ebrahimi - Science Department, Iran Polymer and Petrochemical Institute, Tehran, Iran.
Jalal Barzin - Science Department, Iran Polymer and Petrochemical Institute, Tehran, Iran.
Hamid Mobedi - Science Department, Iran Polymer and Petrochemical Institute, Tehran, Iran.

In order to explicate the important drug release mechanisms, mathematical modeling plays an important role so as to design a predictable pharmaceutical products and avoidance of tryingout various inconspicuous specimens [1]. In the present study the influence of polymer end group functionality on a modeldrug (Naltroxone) release profiles are analyzed using three semi-empirical models: First-Order, Hixson and Gallagher-Corrigan equations and the correlation coefficients were chosen to define the approximation accuracy of models