Nano- and microcrystalline ZnO is an inexpensive, easily synthesized material with a multitude of applications. Its usefulness in the present and future stems from its exceptional optoelectronic, structural, and chemical characteristics as well as a broad range of production techniques. One application comes from its ability to inhibit bacterial growth. Despite the well-documented, vigorously studied antimicrobial action of ZnO particles, the most fundamental physical and chemical mechanisms driving growth inhibition are still not well identified. Particularly, the nature of interactions between ZnO surfaces and extracellular material is not totally clear. This is important given the anisotropic lattice of ZnO leading to two characteristically different lattice terminations: polar and nonpolar, polar being electrically charged with many defect sites and nonpolar being electrically neutral while remaining relatively defect-free. In this work, we employ a hydrothermal growth protocol that allows us to produce ZnO microcrystals with dependable control of morphology and, particularly, the relative abundances of polar and nonpolar free surfaces. This functions as a platform for our investigations into surface-surface interactions behind the antibacterial action of ZnO microcrystals. In our studies, we produced ZnO crystals comparable in size or larger than Staphylococcus aureus bacteria. This was done intentionally to ensure that the ZnO particles would not internalize into the bacterial cells. Our experiments were performed in conjunction with surface photovoltage studies of ZnO crystals to characterize electronic structure and charge dynamics that might be contributing to the antibacterial properties of our samples. We report on the interactions between ZnO microcrystalline surfaces and extracellular material of Staphylococcus aureus bacteria.

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具有可控晶体形态的微米级氧化锌作为研究金黄色葡萄球菌抗菌作用的平台

纳米和微晶 ZnO 是一种廉价、易于合成的材料，具有多种应用。它在现在和未来的实用性源于其卓越的光电、结构和化学特性以及广泛的生产技术。一种应用来自其抑制细菌生长的能力。尽管 ZnO 颗粒的抗菌作用得到充分记录和深入研究，但驱动生长抑制的最基本的物理和化学机制仍未得到很好的确定。特别是，ZnO 表面和细胞外物质之间相互作用的性质尚不完全清楚。考虑到 ZnO 的各向异性晶格导致两个特征性不同的晶格终止：极性和非极性，这一点很重要，极性带电，带有许多缺陷位点，非极性带电中性，同时保持相对无缺陷。在这项工作中，我们采用了一种水热生长协议，使我们能够生产具有可靠控制形态的 ZnO 微晶，特别是极性和非极性自由表面的相对丰度。这作为我们研究 ZnO 微晶抗菌作用背后的表面 - 表面相互作用的平台。在我们的研究中，我们生产的 ZnO 晶体的尺寸与 极性和非极性自由表面的相对丰度。这作为我们研究 ZnO 微晶抗菌作用背后的表面 - 表面相互作用的平台。在我们的研究中，我们生产的 ZnO 晶体的尺寸与 极性和非极性自由表面的相对丰度。这作为我们研究 ZnO 微晶抗菌作用背后的表面 - 表面相互作用的平台。在我们的研究中，我们生产的 ZnO 晶体的尺寸与金黄色葡萄球菌细菌。这样做是为了确保 ZnO 颗粒不会内化到细菌细胞中。我们的实验与 ZnO 晶体的表面光电压研究结合进行，以表征可能有助于我们样品抗菌性能的电子结构和电荷动力学。我们报告了 ZnO 微晶表面与金黄色葡萄球菌细胞外物质之间的相互作用。