Stimuli-Responsive Hydrogels for Controlled Drug Delivery in Oncology: A Comprehensive Review

Abstract

Advancements in cancer treatment have been significant, but challenges remain with traditional methods
such as chemotherapy and radiation, which often suffer from poor specificity, toxicity, and drug resistance.
This highlights the need for more targeted drug delivery systems. On-demand, stimuli-responsive hydrogels
offer a promising solution, capable of releasing drugs in response to biological signals from the tumor
microenvironment. However, clinical challenges such as biocompatibility, scalability, and regulatory
constraints still hinder their widespread adoption. This review explores hydrogels that react to pH, temperature,
and enzyme activity–key traits of cancerous tissues. These “smart” materials improve drug bioavailability,
reduce off-target effects, and enhance patient responses. We also discuss advanced hydrogels with multiple
responsive elements, helping counteract drug resistance. While these hydrogels are transforming cancer
therapy, challenges such as biocompatibility, scalability, and regulatory hurdles persist. Future directions may
leverage emerging technologies such as artificial intelligence to optimize hydrogel design, paving the way for
safer, more effective, and personalized treatments.