Pharmaceutical Science

The term “nanogel” describes hydrogel nanoparticles composed of cross-linked hydrophilic polymer networks. This review highlights the various types, applications, and evaluation strategies for nanogels, which are emerging as a highly promising platform for drug delivery. Nanogels demonstrate significant potential in areas such as chemotherapy, diagnostics, targeted organ delivery, and the administration of bioactive compounds. While conventional macroscopic gels react to environmental stimuli relatively slowly and often face challenges like poor pharmacokinetics, limited in vivo stability, and potential toxicity, nanogels and other nanoscale carriers are helping to overcome these limitations. These nanoparticles can selectively swell or collapse in response to external pH changes, offering precise control over drug release. Nanogel formulations represent a convergence of advanced technology and herbal therapeutics, providing innovative delivery systems for herbal drugs due to their high encapsulation efficiency, uniformity, low toxicity, and enhanced stability. This article primarily reviews general strategies and recent advancements in the field. Nanogels are notable for their uniform size, tunable dimensions, minimal toxicity, stability in serum, and responsive behavior, along with high drug-loading capacity. Additionally, current biomedical applications and ongoing clinical trials involving nanogels are briefly summarized. The discussion focuses on different types of nanogels, their synthesis methods, and mechanisms of drug release. Overall, nanogels have gained significant attention as versatile drug delivery systems, particularly for site-specific and controlled release of therapeutic agents.