A Review on Physicochemical Characteristics, Classification, Synthesis, Applications of Nanogels as Novel Drug Delivery Systems

Review Article

Abstract

Nanogels are a class of three-dimensionally crosslinked polymeric networks that bridge the gap between macroscopic hydrogels and colloidal nanoparticles. These nanosized constructs possess unique features such as high-water content, mechanical flexibility, and a high surface area-to-volume ratio, facilitating the efficient encapsulation of diverse therapeutic payloads ranging from small molecules to biologics. The integration of stimuli-responsive elements allows for autonomous drug release in response to localized physiological triggers like pH gradients, redox potential, and enzymatic activity, thereby enhancing therapeutic index while minimizing systemic toxicity. Fabrication methods involving both top-down lithographic techniques and bottom-up chemical polymerization provide precise control over morphological and topological parameters. Despite superior performance in preclinical models for oncology, neurology, and inflammatory disorders, clinical transition faces hurdles including manufacturing scalability, potential immunogenicity of PEGylated surfaces, and the need for standardized regulatory pathways. Future advancements utilizing bioorthogonal chemistry and computational modeling are essential to refine the pharmacokinetic profiles of these systems. The maturation of nanogel technology signifies a shift toward personalized nanomedicine, where delivery platforms are tailored to specific pathological microenvironments to ensure optimal clinical outcomes