Abstract—

The anatase nanoparticles are stabilized with titanium tetraisopropoxide Ti[OCH(CH₃)₂]₄ and isopropyl alcohol without surfactants suitable for biological studies. We showed that the hydrodynamic radii in suspensions depend on temperature and the duration of hydrolysis, whereas the composition (a mixture of anatase with brookite, anatase, brookite, and rutile) and the sizes of crystallites (X-ray), nanoparticles, and aggregates (SEM) in the dried state are mainly dependent on the pH of the environment. The nonphase of the samples stems from coherent intergrowth of unit cells of anatase and brookite via geometric and structural complementarity. We found that photocatalytic activity (PCA; Rhodamine 6G model dye under UV radiation) depends on OH/H₂O ratio (adsorbed), whereas antimicrobial activity (AMA) in the dark depends on an amount of free water on the surface of nanoparticles according to X-ray photoelectron spectroscopy (XPS). We revealed that samples with the smallest sizes of nanoparticles of all levels possess the highest PCA and AMA relative to Staphylococcus aureus and Escherichia coli.

中文翻译：

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稳定的二氧化钛纳米粒子：制备及理化，光催化和抗菌性能

摘要—

锐钛矿型纳米颗粒用四异丙醇钛Ti [OCH（CH ₃）₂ ] ₄和异丙醇稳定，没有适合生物学研究的表面活性剂。我们证明了悬浮液的流体动力学半径取决于温度和水解时间，而其组成（锐钛矿与板钛矿，锐钛矿，板钛矿和金红石的混合物）以及微晶的尺寸（X射线），纳米颗粒和聚集体（SEM）在干燥状态下主要取决于环境的pH值。样品的非相来自于锐钛矿和板钛矿的晶胞通过几何和结构互补的相干共生。我们发现光催化活性（PCA；若丹明6G模型染料在紫外线辐射下）取决于OH / H ₂根据X射线光电子能谱（XPS），O比率（被吸附），而在黑暗中的抗菌活性（AMA）取决于纳米颗粒表面上的自由水量。我们发现相对于金黄色葡萄球菌和大肠埃希菌，具有最小尺寸的纳米颗粒的样品具有最高的PCA和AMA 。