Antibacterial Activity of Hydrogels Produced from Nanocellulose Derivatives for Controlled Drug Delivery

Hydrogels are a 3D polymer network capable of absorbing large amounts of water or biological fluids without dissolving, due to chemical or physical crosslinking. They are made from cellulose derivatives and are a promising research area for developing smart drug carriers in modern drug delivery systems. The present research aimed to synthesize hydrogels based on nanocellulose derivatives and evaluate their antibacterial activity. A crosslinker termed epichlorohydrin (ECH) was incorporated into Sengon plant cellulose to produce cellulose derivatives, specifically abietic nanocellulose (CAB). Hydrogels were synthesized from the nanocellulose derivatives. The hydrogels were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM). The degree of substitution, release, and swelling tests, as well as antibacterial activity tests, were conducted. The results of the FTIR spectra revealed absorption between 1400 and 1600 cm^-1, indicating a crosslinking process on the hydrogels. Furthermore, SEM cross-sectional observations demonstrated the formation of pores of various sizes. The hydrogel characterization results showed the impact of the preparation conditions, specifically the ECH concentration. The nanocellulose derivatives (NCAB): ECH concentration ratio varied between 1:0.5, 1:1, and 1:2. Based on the research results, the highest hydrogel swelling ratio was found in the CAB: ECH reaction conditions, which was 1:0.5. The findings of the present study demonstrated that modification by rosin esterification can result in hydrogels with desirable properties that can be employed for controlled drug delivery. Hydrogel from NCAB can inhibit the growth of E. coli bacteria in the weak category, but is moderate against S. aureus.