A Comprehensive Study on the Development of Stimuli-Responsive Smart Polymer Systems for Controlled Drug Delivery

Abstract

Stimuli-responsive smart polymers are in a paradigm shift of pharmaceutical delivery systems that can be used to control drug release kinetics in unprecedented detail through external and internal environmental triggers. This study systematically addresses the development, characterization and clinical applications of smart polymer systems for controlled drug delivery. The research goals were to evaluate the effectiveness of pH responsive, temperature responsive, and dual-stimulus polymers in altering drug release patterns, and to correlate the polymer's physicochemical attributes to therapeutic effects. The methodology used was a comprehensive systematic review, which included a review of 87 published studies (2019-2025) from peer-reviewed journals from PubMed and Google Scholar. This hypothesis proposed that polymers with multiple stimulus-responsive properties would exhibit higher bioavailability (>75%) than polymers with a single stimulus-responsive property. The results showed that the pH-responsive poly (methacrylic acid) systems showed drug release efficiency in the range of 68–82% in simulated intestinal fluid and the temperature-responsive poly(N-isopropylacrylamide) systems showed precise release with minimal burst release (<15%) at temperature 37°C. The optimal performance was observed for dual-stimulus systems (pH and temperature responsiveness) and 85-92% cumulative drug release with lower cytotoxicity profiles. The release kinetics of different polymer types were significantly different (p<0.05) based on the statistical analysis. Overall, multi-stimulus responsive polymer systems exhibit a better controlled release profile and thus higher therapeutic potential for the treatment of cancer, diabetes and inflammatory diseases and thus, are promising to be translated into clinical applications.

Keywords: Stimuli-responsive polymers; Controlled drug delivery; Smart polymer systems; pH-responsive hydrogels; Drug release kinetics.