Synthesis and Effect of Covalent Crosslinking Agents (Aldehyde Groups) on Properties of Maize Corn Cob Cellulose-Chitosan Gel Beads and Antimicrobial Assay

Abstract Novel cellulose-chitosan crosslinked polymers were synthesized using a Schiff base reaction by combining cellulose extracted from corn cobs via chemically treated methods (NaOH, H 2 O 2 /NaOH) and shrimp chitosan with aldehyde linkers (glutaraldehyde and formaldehyde). Structural, compositional, and chemical characterization of the fiber was performed using SEM, FTIR, UV-Vis, XRD, and EDX analyses. Treatment with H₂O₂ effectively removed waxy and fatty acid residues from the cellulose surface without altering its chemical composition. FTIR analysis confirmed the presence of aldehyde crosslinking, with variations in peak intensities (around 1400 cm⁻¹) indicating differential interactions between formaldehyde and glutaraldehyde linkers. SEM revealed an amorphous microstructure with compact, globular particles of varying sizes. Crosslinking enhanced antibacterial activity, as demonstrated by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 9.37 mg/mL and 18.75 mg/mL, respectively, against Staphylococcus aureus and Pseudomonas aeruginosa . These results highlight the potential of cellulose-chitosan crosslinked polymers as effective antimicrobial agents, with aldehyde crosslinking playing a pivotal role in improving their efficacy.