ABSTRACT

Green synthesis of metal nanoparticles and nanocomposites offers numerous advantages over conventional methods. The present study deals with the synthesis of Ag nanoparticles and Ag@MoS2 nanocomposites by Dracocephalum kotschyi extract as a reductant and a stabilising agent. The influence of extract volume, reaction temperature, contact time and pH on the synthesis of d-AgNPs was investigated. Further, the modified MoS2 using D. kotschyi extract (d-MoS2) could deposit Ag+ ions onto the MoS2 nanosheets surface, reduce the ions to AgNPs, and stabilise the reduced particles effectively. The synthesised nanostructures were characterised by XRD, SEM-EDS, TEM, Zeta potential and FT-IR analysis. Ag nanoparticles are spherical with diameter of 58–75 nm for d-AgNPs and 35–55 nm for Ag@d-MoS2, respectively. The d-AgNPs exhibited high activity in the inhibition of acetylcholinesterase. Also, loading of AgNPs on MoS2 nanosheets resulted in the increase of inhibitory activity against acetylcholinesterase compared to MoS2 nanosheets.

摘要

与传统方法相比，金属纳米颗粒和纳米复合材料的绿色合成具有许多优势。本研究涉及由Dracocephalum kotschyi合成 Ag 纳米颗粒和 Ag@MoS2 纳米复合材料提取物作为还原剂和稳定剂。考察了提取量、反应温度、接触时间和pH对d-AgNPs合成的影响。此外，使用 D. kotschyi 提取物 (d-MoS2) 改性的 MoS2 可以将 Ag+ 离子沉积到 MoS2 纳米片表面，将离子还原为 AgNPs，并有效地稳定还原后的粒子。通过XRD、SEM-EDS、TEM、Zeta电位和FT-IR分析对合成的纳米结构进行了表征。Ag 纳米粒子是球形的，d-AgNPs 的直径为 58-75 nm，Ag@d-MoS2 的直径为 35-55 nm。d-AgNPs 在抑制乙酰胆碱酯酶方面表现出高活性。此外，与 MoS2 纳米片相比，在 MoS2 纳米片上负载 AgNP 导致对乙酰胆碱酯酶的抑制活性增加。