Electronic Theses and Dissertations

Date of Award


Document Type


Degree Name

M.S. in Pharmaceutical Science

First Advisor

Michael A. Repka

Second Advisor

Eman Ashour

Third Advisor

Dr. Walter Chambliss


University of Mississippi

Relational Format



This work aimed to develop a novel gastroretentive floating drug delivery system based on non-effervescent technology using hot melt extrusion technology to synergize gastric floating and bioadhesion strategies to achieve extended drug release. All components of the formulations including the active pharmaceutical ingredient (API) of the drug (theophylline), the polymers acting as a floating matrix and achieving the adhesive function (chitosan, HPC HF, HPMC K4M, and PEO N80), and the gas generating agent sodium bicarbonate were directly fed into the hot melt extruder to prepare the novel gastroretentive pellets. The uniformity of all formulations met the United States Pharmacopeia criteria. Additionally, in vitro drug release studies were performed in pH 1.2 buffer solution, and all formulations were capable of extended release for up to 24 hours. F1, F2, F5, and F6 could maintain buoyancy throughout the entire dissolution process while exhibiting bioadhesive properties in the bioadhesion study. The kinetics of the drug release followed the first order, Hixson-Crowell, and Korsmeyer-Peppas model. Moreover, the stability data indicated that all these formulations showed no significant difference in appearance, physical statement, weight, and drug content after storing at 40 °C/75% RH for 30 days.

Available for download on Saturday, September 13, 2025