Electronic Theses and Dissertations

Date of Award


Document Type


Degree Name

Ph.D. in Pharmaceutical Sciences


Pharmaceutics and Drug Delivery

First Advisor

Michael A. Repka

Second Advisor

Soumyajit Majumdar

Third Advisor

S. Narasimha Murthy

Relational Format



Hot melt extrusion (HME) is a leading technology that can be applied to many pharmaceutical preparations as solid dispersions. Part of this research project focus on injecting pressurized carbon dioxide (P-CO2) gas during the HME process. These combined techniques have an additional advantage of being adaptable and portable to a hot melt extruder instrument. The use of HME alongside with other techniques (P-CO2 or co extrusion process) for preparing an improved controlled/sustained release formulation is the main theme of this research project. Current research focusing on Active Pharmaceutical Ingredients (APIs) with good aqueous solubility requires novel approach to obtain tailored drug release for the processed sustained/controlled release formulations. HME, when combined with other novel techniques has been shown to be a practicable method for the development of novel floating drug delivery systems. This research also focused on the feasibility of HME/P-CO2and HME/co extrusion techniques to prepare the intended formulation with specific properties with detailed explanation of the resulting dosage forms. Also, it explores the effects of different formulation variables and process parameters on the quality of final product. These studies of research facilitate the development of floating drug delivery devices, as well as improving the consistency of the powder flow while processing which result in with improved drug content with comparable sustained release profile to the marketed formulation. The key objectives of this dissertation chapters are: (1) to introduce HME as an efficient technique alongside when combined with other novel techniques in pharmaceutical industry; (2) to prepare floating mini tablets of acetaminophen (APAP) with the hydrophobic carriers Eudragit® RL PO and Eudragit® RS PO by HME/P-CO2 and to evaluate the buoyancy efficiency through in-vitro methods. Moreover, scanning electron microscopy (SEM) was utilized to visually investigate the morphological change of the matrix; (3) to develop of sustained-released donepezil hydrochloride (DH) formulations with various hydrophobic carriers utilizing HME technique alone to optimize hot melt process parameters for obtaining the desirable sustained release profile ; (4) to develop and evaluate a sustained-release DH formulation with improved & consistent drug content and tablet content uniformity via co extrusion tablet filler through the extruder.



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