Enhanced antimicrobial efficacy of biogenic ZnO nanoparticles through UV-B activation: A novel approach for textile garment

Abstract

Zinc oxide nanoparticles (ZnO NP) are characterized by novel properties which have been attracting the attention of different lines of research due to their wide applicability. Obtaining this nanomaterial is strongly linked to biogenic synthesis methods, which have also been developed in this research, using Coriandrum sativum extract as a reducing agent. ZnO NPs have been properly characterized by techniques to evaluate their morphology by transmission electron microscopy (TEM) and elemental analysis by EDX. The evaluation of the antimicrobial and antifungal effects is linked to the use of a system provided by "locker sanitizer" equipment, which has been designed and built as part of this research, and is intended to treat textile garments by nebulizing the ZnO NP colloid (99.08 μg/mL) + UV-B, water + UV-B, and UV-B only, and also to evaluate the influence of the treatment time for 1, 2 and 3 min. In this sense, it is known that the nanomaterial used shows a better response to UV light because more hydroxyl radicals are produced, leading to a higher reaction rate, which results in greater efficiency in inhibitory processes. The results show that the use of the locker sanitizer is more efficient when using ZnO NP + UV-B light since it achieved 100 % growth inhibition against E. coli, C. albicans, and A. brasiliensis, and >99 % against S. aureus, after 3 min of treatment.

Keywords: Sanitization; UV disinfection; UV photoactivation; ZnO nanoparticles.

Fig. 1

Design of the locker sanitizer.

Fig. 2

Characterization of ZnO NPs by (a) Transmission electron microscopy, (b) Size histogram, (c) Elemental analysis by EDX, (d) XRD ZnO NPs.

Fig. 3

Representative photos of Colony Forming Units of E. coli in (a) negative control and UV light treatment at 1, 2, and 3 min (top section) and (b) negative control and ZnO NP + UV light at 1, 2, 3 min.

Fig. 4

Representative photos of Colony Forming Units of S. aureus in (a) negative control and UV light treatment at 1, 2, and 3 min and (b) negative control and ZnO NP + UV light at 1, 2, and 3 min.

Fig. 5

Representative photos of Colony Forming Units of C. albicans in (a) negative control and UV light treatment at 1, 2, and 3 min and (b) negative control and ZnO NP + UV light at 1, 2, and 3 min.

Fig. 6

Representative photos of Colony Forming Units of A. brasilienses in (a) negative control and UV light treatment at 1, 2, and 3 min and (b) negative control and ZnO NP + UV light at 1, 2, and 3 min.