DESIGN, PHYSICOCHEMICAL CHARACTERIZATION, AND DEVELOPMENT OF A MATRIX DIFFUSION-CONTROLLED TRANSDERMAL PATCH OF RASAGILLINE FOR SUSTAINED ANTI-PARKINSON’S THERAPY

Objective: This study aimed to design and evaluate diffusion-controlled transdermal patches of rasagiline for sustained management of Parkinson’s disease. Methods: Matrix patches were prepared using the selected copolymers with 30% w/w dibutyl phthalate as plasticizer. Patches were evaluated for mechanical, physicochemical, and permeability characteristics. Drug–polymer compatibility was confirmed by Fourier Transform Infrared Spectroscopy (FTIR) and Differential scanning calaromitry (DSC). Various permeation enhancers (isopropyl myristate [IPM], eucalyptus oil, Span® 80, Tween® 20, and limonene) were incorporated at 2–10% w/w, and their effects were assessed through in vitro and ex vivo studies using Franz diffusion cells. Results: All rasagiline patches exhibited smooth surfaces, flexibility, and uniform thickness. FTIR and DSC confirmed absence of drug–excipient interactions. The optimized RL:RS (7:3) formulation achieved a sustained 92.3% cumulative drug release after 24 hours, following Higuchi diffusion kinetics. Among all enhancers, IPM (10% w/w) produced the highest improvement, yielding a 5.4-fold increase in skin flux (53.7 µg/cm²·h) compared to control, and a total permeation of 1,342.9 µg/cm² after 24 hours. Conclusion: The optimized rasagiline patch composed of Eudragit® RL:RS (7:3) and 10% IPM achieved controlled drug release and significantly enhanced transdermal permeation. This system demonstrates strong potential for improving rasagiline bioavailability and patient compliance in Parkinson’s disease therapy.