Low-surface-energy cotton fabrics for hygiene control: Super-repellent surfaces resistant to biological and non-biological contamination

Cotton fabrics are widely used in industries like agriculture and food processing, where they are often chosen for workwear, cleaning purposes, and as reusable cloths. Nevertheless, their inherent hydrophilicity and porous morphology facilitate the absorption and persistence of various biological substances, resulting in staining, accumulation of contaminants, and elevated risks of cross-contamination. In this study, we present a simple and scalable method to impart robust antifouling properties to cotton fabrics via one-step air-spray deposition of super-repellent nano silica (SRNS). XPS analysis confirmed successful chemical modification of the cotton surfaces. This treatment converted the originally hydrophilic cotton surface into a stable superhydrophobic interface, as evidenced by a water contact angle of 155.9 ± 1.9°. This performance was attributed to the combination of low-surface-energy chemistry and the introduction of hierarchical surface roughness via nanoparticle incorporation. As a result, SRNS-coated cotton fabrics (SRNS-CF) exhibited significant reductions in microbial adhesion, specifically inhibiting Aspergillus niger (by 83.3%) and Escherichia coli (by 99.9%) attachment in both agar plate and SEM-based evaluations. Furthermore, SRNS-CF effectively suppressed protein adsorption, recording an intensity of 0.30 via UV-Vis spectroscopy and a low sliding angle of 2.96°. The treated fabrics also markedly limited blood adhesion, with a sliding angle of 2.79° indicative of superior liquid-shedding capabilities. Additionally, gravimetric analysis demonstrated a mud anti-adhesion efficiency of 92.5%. Finally, the stability of SRNS-CF was confirmed through washing durability and chemical leaching tests. In summary, this spray-based approach offers a practical solution for producing reusable, biologically antifouling and durable cotton fabrics that enhance hygiene for food safety.