In this study, zinc oxide nanoparticles (ZnO NPs) were
synthesized
using an aqueous extract of the Ocimum lamifolium (O. lamifolium) plant. The I-optimal coordinate
exchange randomized response surface methodology (RSM) was used to
optimize the effect of the zinc acetate precursor, temperature, and
time on ZnO NPs by designing nine runs. From ANOVA analysis, the significance
and validity of the designed model showed that the optimal values
of the zinc acetate precursor, temperature, and time during ZnO NPs
synthesis were found to be ∼0.06 M, ∼30 °C, and
∼1.35 h, respectively. The obtained ZnO NPs under these optimized
conditions were characterized and explored by UV–vis, TGA/DTA,
FTIR, XRD, SEM-EDX, TEM, HRTEM, and SAED. Furthermore, the electrocatalytic
performance of ZnO NPs was performed for sulfamethoxazole (SMZ) sensing
activity with a 0.3528 μM (S/N = 3) limit of detection (LOD).
In addition, an antibacterial study revealed that ZnO NPs confirmed
an excellent zone of inhibition against E. coli, S. aureus, P. aeruginosa, and S.
pyogen pathogenic drug resistance bacterial strains at concentrations
of 50, 75, and 100 μg/mL. Thus, ZnO NPs synthesized using the O. lamifolium leaf have a potential electrocatalytic activity
for diverse organic pollutant detection as well as a desirable material
for such drug resistance antimicrobial strains.