Evaluation of Nano-Zinc Borate Effects on Thermal Properties, Morphology, Antibacterial Activity, and Drug Release Behavior of Starch/Gelatin Hydrogel Films for Biomedical Applications

Starch and gelatin offer opportunities for use due to their non-toxicity, biocompatibility, physical and functional properties. In this study, different amounts of nano-zinc borate were added to starch/gelatin composition for biological applications and their properties were studied. The structure of the films was investigated by various techniques. Nanostructured zinc borate was synthesized using a chemical method and particle sizes were determined as 196 nm. The atenolol drug was doped into the polymer composite. The atenolol release was performed at pH 7.4 and in phosphate-buffered saline solution medium. Cumulative drug release was 76% with the inclusion of nano-zinc borate in the polymer mixture. The atenolol release was approximately 50%–70% in films with nano-zinc borate added after 300 min. Furthermore, thermal resistance of the films improved with the addition of nano-zinc borate. The investigated chemical compound exhibited pronounced antibacterial activity against Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus), with significantly greater potency compared to Gram-negative bacteria (E. coli and Pseudomonas aeruginosa). Notably, the formulation containing 1.5% starch, 0.5% gelatin, and 1% nano-zinc borate demonstrated broad-spectrum efficacy against all tested pathogens, highlighting its potential as a promising antibacterial agent. The observed differential activity against bacterial strains suggests that fine-tuning the concentrations of starch, gelatin, and nano-zinc borate may optimize antibacterial efficacy and broaden the spectrum. The results showed us that non-toxic and biocompatible polymer films can be realized in pharmaceutical industry systems and biomedical applications.