Department of Biology, Payame Noor University, Tehran, Iran.
Department of Biotechnology, College of Agriculture & Natural Resources, University of Tehran, Karaj, Iran.
Nanotechnology. 2022 Jul 7;33(39). doi: 10.1088/1361-6528/ac79bc.
Presence of inorganic pollutants in water reservoirs is the treating factor for human health and environment. Semiconductor quantum dots (QDs) has been regarded as one of the most efficient nanoparticles for their enhanced photocatalytic activity. Medicinal plants are the safe sources to provide green template for biosynthesis of inorganic nanoparticles such as quantum dots. In order to determine the photocatalytic and biological application of cadmium sulfide quantum dots (CdS QDs), a biosynthesis approach was employed using saffron () stigma extract as the green reaction substrate. The biosynthesis process was evaluated at different pH condition to obtain the most efficient CdS QDs. Characterization of prepared CdS QDs were determined through UV-vis and fluorescence spectroscopy, FTIR and TEM analysis. The obtained results showed well dsispersed and uniform QDs during green synthesis at the optimum condition. The absorption and electrical properties of green synthesized CdS QDs showed the lowest energy bandgap of 2.4 at pH 11. Photocatalytic activity of CdS QDs on Rhodamine B degradation showed 92% degradation after 80 min under UV light irradiation. The antibacterial and cell cytotoxicity of green synthesized CdS QDs were assayed by disk diffusion and MTT assays respectively. Obtained results showed significant antibacterial effect of CdS QDs against gram-positive and gram-negative bacteria including(90%) and(96%) respectively. Moreover, cytotoxicity of prepared CdS Qds through MTT assay indicated 79% apoptosis induction on MCF-7 breast cancer cells.
水库存中无机污染物的存在是影响人类健康和环境的因素之一。半导体量子点 (QDs) 因其增强的光催化活性而被认为是最有效的纳米粒子之一。药用植物是提供绿色模板用于合成无机纳米粒子（如量子点）的安全来源。为了确定硫化镉量子点 (CdS QDs) 的光催化和生物应用，采用了一种生物合成方法，使用藏红花 ()柱头提取物作为绿色反应底物。在不同的 pH 条件下评估了生物合成过程，以获得最有效的 CdS QDs。通过紫外-可见和荧光光谱、FTIR 和 TEM 分析来确定制备的 CdS QDs 的特性。结果表明，在最佳条件下，绿色合成过程中形成了良好分散且均匀的 QDs。绿色合成的 CdS QDs 的吸收和电学性质显示在 pH 11 时具有最低的能隙为 2.4。CdS QDs 在 Rhodamine B 降解上的光催化活性在 UV 光照射 80 分钟后显示出 92%的降解率。通过圆盘扩散和 MTT 测定法分别测定了绿色合成的 CdS QDs 的抗菌和细胞细胞毒性。结果表明，CdS QDs 对革兰氏阳性和革兰氏阴性细菌（包括 90%和 96%）均具有显著的抗菌作用。此外，通过 MTT 测定法制备的 CdS Qds 的细胞毒性表明，在 MCF-7 乳腺癌细胞上诱导了 79%的凋亡。
