Ultrasound-Assisted Synthesis of ZnO–Te/TeO2 Nanocomposite for Multidrug-Resistant Microorganisms and Biofilm Eradication

Abstract

The spread of multidrug-resistant (MDR) pathogens demands antimicrobial materials that combine tunable surface chemistry with durable, non-antibiotic kill mechanisms. We reported a sonication–freeze–dry route to hybrid ZnO-nanorod–decorated Te/α-TeO2 sheets and demonstrated that interfacial strain-engineering at the ZnO–Te/TeO2 heterointerface dramatically enhances antimicrobial potency across Gram-negative, Gram-positive, and fungal MDR strains. Structural analysis shows a two-phase Te/α-TeO2 host (~68% Te: ~32% α-TeO2) whose oxide sublattice accumulates microstrain and defects as ZnO loading increases (α-TeO2: Dmin ≈ 39.8 nm, εmax ≈ 0.384% at 40% ZnO), while Te domains recover crystallinity at 50% ZnO, consistent with strain redistribution. The best formulation (Z7, 50% ZnO- Te/α-TeO₂) produced the largest inhibition zones against Klebsiella pneumoniae (36.64±3.5 mm) and Escherichia coli (34.70±3.6 mm), achieved growth reduction efficiency of 96.45 ± 2.54% and 94.19 ± 1.63%, respectively, and showed an MIC of 1.95 mg·mL-1 (MBC 7.81 mg·mL⁻1) versus K. pneumoniae. Long-term dynamic viability analysis demonstrates complete eradication of planktonic growth within 78–90 h, depending on strain. Mechanistically, enhanced ROS production together with strong interfacial membrane disruption are proposed as potential mechanisms. The material’s structural tunability, facile synthesis, and broad anti-MDR performance make it promising for hospital coatings and infection-resistant surfaces.