Investigation of the properties of chitosan–Pluronic based nanogel drug delivery systems utilizing various Pluronic types

This research aimed to create self‐assembled nanogel particles using chitosan grafted with various types of Pluronic to encapsulate curcumin, a hydrophobic biological agent. The study explored the properties of CS–Pluronic nanogels using Pluronic types L61, P123, F127, and F68, each varying in hydrophilic–lipophilic balance (HLB) index. Findings indicated that the critical micelle concentration (CMC) of Pluronics and CS–Pluronic copolymers did not depend on the HLB values but were influenced by the structural characteristics of each Pluronic type. The efficiency of curcumin encapsulation within the nanogels correlated with the CMC values of the CS–Pluronic copolymers, where lower CMC values resulted in higher encapsulation efficiencies. The curcumin‐loaded nanogels were spherical, positively charged, and had an average diameter under 200 nm. Controlled, pH‐dependent release of curcumin was observed in vitro studies conducted at 37°C in PBS at pH levels of 7.4 and 5.0, with a faster release in acidic conditions. Biocompatibility testing indicated that nanogel biocompatibility was influenced by the HLB value of Pluronic, with lower HLB values associated with reduced biocompatibility. Cytotoxicity testing revealed that curcumin‐loaded nanogels had increased cytotoxicity on MCF‐7 cells compared to free curcumin. CS–P123 emerged as the most effective carrier, meeting biocompatibility and stability requirements during storage.Highlights CS–Pluronic serves as an effective hydrophobic drug delivery system. The capacity of CS–Pluronic to encapsulate hydrophobic drugs is determined by its CMC value rather than its HLB index. CS–Pluronic is a copolymer known for its excellent biocompatibility. CS–Pluronic increases the toxicity of curcumin in nanogels compared to free curcumin.