Department of Physics, Jadavpur University, Kolkata 700032, India.
Department of Life Science and Biotechnology, Jadavpur University, Kolkata 700032, India.
J Nanosci Nanotechnol. 2019 Nov 1;19(11):7112-7122. doi: 10.1166/jnn.2019.16658.
The size-dependent antibacterial activities of three minerals namely; alkali feldspar, calcite and stibnite are reported as examined individually against and by evaluating minimum inhibitory concentration (MIC) with colony counting method, along with cell survivability assay (MTT). Each of these minerals were grinded into fine-size fractions-S1 (bulk), S₂ (ball milled) and S3 (nanosized) and spectroscopically characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and ultraviolet-visible (UV-Vis) spectroscopy. Antibacterial activity was found to be highest in the nanosized (S3) minerals. Interaction between bacteria and nanosized mineral samples produce intracellular reactive oxygen species (ROS), which might cause higher bacterial mortality. The penetration due to nano-dimension is another significant observation as evidenced by bacterial FESEM micrographs. The current findings thus provide a pathway for future research on antibacterial products retrievable from widely available geological materials. The size dependant antibacterial activity of naturally formed minerals is a new insight to reduce bacterial contamination in living systems.
报告了三种矿物质（碱长石、方解石和辉锑矿）的尺寸依赖性抗菌活性，通过评估最小抑菌浓度（MIC）和细胞存活率测定（MTT），单独针对 和 进行了检测。将这些矿物质分别研磨成细颗粒-S1（大块）、S₂（球磨）和 S3（纳米级），并使用 X 射线衍射（XRD）、场发射扫描电子显微镜（FESEM）和紫外可见（UV-Vis）光谱对其进行了光谱特性分析。纳米级（S3）矿物质的抗菌活性最高。细菌与纳米级矿物样品之间的相互作用会产生细胞内活性氧（ROS），这可能导致更高的细菌死亡率。由于纳米尺寸的穿透性是另一个重要的观察结果，这可以从细菌 FESEM 显微照片中得到证明。因此，这些发现为从广泛可用的地质材料中获取可用于抗菌产品的未来研究提供了一条途径。天然形成的矿物质的尺寸依赖性抗菌活性是减少生活系统中细菌污染的新见解。
