Sustainable Chitosan-Based Nanoparticles for Curcumin Delivery: Assessment of Chemical Integrity and Antibacterial Activity Against Escherichia coli

Abstract Curcumin (CUR) is a natural polyphenol with recognized antibacterial and antioxidant properties, whose biomedical application is limited by poor aqueous solubility, low bioavailability, and rapid chemical degradation under physiological conditions. In this study, green and sustainable chitosan-fatty acid nanoparticles were developed through a mild cosolvent evaporation strategy to improve CUR stability and facilitate antibacterial activity while avoiding harsh preparation conditions. The obtained nanosystem showed that CUR encapsulation and formation of stable nanosized particles are suitable for aqueous dispersion and biological applications, since curcumin was efficiently transported into the intracellular compartment of Escherichia coli. This was used as Gram-negative bacterium to investigate the antibacterial activity of encapsulated CUR. In addition, the chitosan-based carrier effectively preserved the chemical integrity of CUR both during nanoparticle preparation and under physiological conditions. The combined effects of sustainable formulation, improved CUR stability, and antibacterial activity highlight the potential of these chitosan-based nanoparticles as effective delivery systems for poorly soluble bioactive molecules. Overall, the proposed strategy represents an environmentally friendly platform for the development of advanced antimicrobial nanomaterials based on natural polymers.