Locust bean gum-based silver nanocomposite hydrogel as a drug delivery system and an antibacterial agent

Effective drug release is of utmost importance in the medical field for treating various diseases, particularly cancer. Nanocomposite hydrogels remain the best materials for enhancing the bioavailability and therapeutic levels of drugs as they enable sustained, targeted, or controlled drug release. In this work, a nanocomposite hydrogel containing locust bean gum (LBG), poly(4-acryloylmorpholine) (PAcM), and silver nanoparticles (SN) has been made using an eco-friendly microwave (MW)-assisted method and characterized by various advanced techniques. The material is evaluated for its potential as a polymer matrix towards delivering 5-fluorouracil (5-FU), an anticancer drug in the gastrointestinal tract, and inhibiting bacterial growth. The pH-dependency of the nanocomposite material towards swelling and drug release and its antibacterial characteristics have been compared with the neat gel in order to understand the role of SN in enhancing the performance of the materials. The results indicated both polymer materials exhibit a pH-dependent release of 5-FU with a higher release at pH 1.2, simulated gastric fluid, than at pH 7.4, simulated intestinal fluid. About 72 % of the loaded drug was released from the nanocomposite, as compared to 44 % from the neat gel at pH 1.2 during the observation period of 3 h. The drug release process could be best explained by the first-order kinetic model and Fickian diffusion transport mechanism. The nanocomposite exhibited remarkable antibacterial activity against Staphylococcus aureus and Escherichia coli. The biocompatibility of the drug-loaded nanocomposite was demonstrated by a cytotoxicity study, which showed higher than 80 % viability of healthy IEC-6 cells. The results indicate the suitability of the developed nanocomposite material as a polymer matrix for sustained release of 5-FU for cancer therapy and also as an antibacterial agent to fight against bacterial infections.