title: Photophysical mechanism for quantum dots-induced bacterial growth inhibition.
abstract: Quantum dots-induced cell growth inhibition effect and its photophysical mechanism were investigated in this report. Cell growth curve and atomic force microscopy show that QDs block cell division to inhibit the growth of bacterial cells. On the basis of combined biological and physical discoveries from cytochrome c reduction assay, hydrodynamic size, photoluminescence and UV-visible spectrometry, a photophysical mechanism involving a polypeptide or amino acid adsorption-mediated fluorescence and reactive oxygen species quenching process is proposed. The photophysical mechanism may not only provide physical insight of QDs-induced toxicity, but also render QDs potentials in antimicrobial and cancer photodynamic therapy applications.
authors.affiliation: School of Chemical and Biomedical Engineering and Center for Advanced Bionanosystems, Nanyang Technological University, 70 Nanyang Drive, Singapore 637457, Singapore.
authors.forename: Zhisong
authors.initials: Z
authors.lastname: Lu
authors.forename: Chang Ming
authors.initials: CM
authors.lastname: Li
authors.forename: Haifeng
authors.initials: H
authors.lastname: Bao
authors.forename: Yan
authors.initials: Y
authors.lastname: Qiao
authors.forename: Qiaoliang
authors.initials: Q
authors.lastname: Bao
mesh_terms: D045304:Cytochromes c / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development*; D029968:Escherichia coli Proteins / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D049449:Luminescence; D010084:Oxidation-Reduction / Q000187:drug effects; D045663:Quantum Dots; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D029968:Escherichia coli Proteins; D017382:Reactive Oxygen Species; D045304:Cytochromes c