biostudies-literatureUnknown11Niu JThe intracellular persistence and biofilm-forming capacity of uropathogenic <i>Escherichia coli</i> (UPEC) are major contributors to urinary tract infections (UTIs) recurrence and antibiotic failure. Here, we report a precisely engineered nanotherapeutic based on ZnO quantum dots (QDs) surface-functionalized with low-molecular-weight polyethylene glycol (PEG200), designed to enhance biocompatibility while preserving potent antibacterial activity. The optimized ZnO@PEG200 QDs exhibited excellent aqueous dispersibility, minimal cytotoxicity, and broad-spectrum efficacy against both drug-sensitive and multidrug-resistant <i>Escherichia coli</i> strains. Mechanistic studies revealed that the QDs exerted multimodal bactericidal effects, including Zn²⁺ ion release, membrane destabilizInternational journal of pharmaceutics: X100479https://www.ebi.ac.uk/biostudies/studies/S-EPMC12808613biostudies-literaturePrecision PEGylation of ZnO quantum dots enables selective intracellular killing of Uropathogenic &lt;i&gt;E. coli&lt;/i&gt; via multimodal antibacterial mechanisms without inducing resistance.PMC12808613Chen QLiang XZhang MLiu SXin HYu HGao MHong YChen ZMiao BDu FNiu JLiu BfalsePrecision PEGylation of ZnO quantum dots enables selective intracellular killing of Uropathogenic &lt;i&gt;E. coli&lt;/i&gt; via multimodal antibacterial mechanisms without inducing resistance.The intracellular persistence and biofilm-forming capacity of uropathogenic <i>Escherichia coli</i> (UPEC) are major contributors to urinary tract infections (UTIs) recurrence and antibiotic failure. Here, we report a precisely engineered nanotherapeutic based on ZnO quantum dots (QDs) surface-functionalized with low-molecular-weight polyethylene glycol (PEG200), designed to enhance biocompatibility while preserving potent antibacterial activity. The optimized ZnO@PEG200 QDs exhibited excellent aqueous dispersibility, minimal cytotoxicity, and broad-spectrum efficacy against both drug-sensitive and multidrug-resistant <i>Escherichia coli</i> strains. Mechanistic studies revealed that the QDs exerted multimodal bactericidal effects, including Zn²⁺ ion release, membrane destabiliz2026-01-01T00:00:00Z2026 Jun2026-06-06T15:42:06.273Z2026-06-02T03:08:53.659ZS-EPMC128086134155198810.1016/j.ijpx.2025.100479