Background: Silver nanoparticles (AgNPs) are widely used in food industries, biomedical, dentistry, catalysis, diagnostic biological probes and sensors. The use of plant extract for AgNPs synthesis eliminates the process of maintaining cell culture and the process could be scaled up under a non-aseptic environment. The purpose of this study is to determine the classes of phytochemicals, to biosynthesize and characterize the AgNPs using Clinacanthus nutans leaf and stem extracts. In this study, AgNPs were synthesized from the aqueous extracts of C. nutans leaves and stems through a non-toxic, cost-effective and eco-friendly method. Results: The formation of AgNPs was confirmed by UV-Vis spectroscopy, and the size of AgNP-L (leaf) and AgNP-S (stem) were 114.7 and 129.9 nm, respectively. Transmission electron microscopy (TEM) analysis showed spherical nanoparticles with AgNP-L and AgNP-S ranging from 10 to 300 nm and 10 to 180 nm, with average of 101.18 and 75.38 nm, respectively. The zeta potentials of AgNP-L and AgNP-S were recorded at −42.8 and −43.9 mV. X-ray diffraction analysis matched the face-centred cubic structure of silver and was capped with bioactive compounds. Fourier transform infrared spectrophotometer analysis revealed the presence of few functional groups of phenolic and flavonoid compounds. These functional groups act as reducing agents in AgNPs synthesis. Conclusion: These results showed that the biogenically synthesized nanoparticles reduced silver ions to silver nanoparticles in aqueous condition and the AgNPs formed were stable and less toxic.

背景：银纳米颗粒（AgNPs）广泛用于食品工业，生物医学，牙科，催化，诊断性生物探针和传感器。将植物提取物用于AgNPs合成可以消除维持细胞培养的过程，并且可以在非无菌环境下扩大该过程。这项研究的目的是确定的植物化学物质的类别，生物合成和表征使用的AgNPs Clinacanthus穗披碱草茎叶提取物。在这项研究中，AgNPs是通过无毒，经济高效和生态友好的方法从C. nutans叶和茎的水提物中合成的。结果：通过UV-Vis光谱法确认了AgNP的形成，并且AgNP-L（叶）和AgNP-S（茎）的尺寸分别为114.7nm和129.9nm。透射电子显微镜（TEM）分析显示球形纳米颗粒，其AgNP-L和AgNP-S的范围分别为10至300 nm和10至180 nm，平均分别为101.18和75.38 nm。在-42.8和-43.9mV处记录AgNP-L和AgNP-S的ζ电位。X射线衍射分析与银的面心立方结构匹配，并被生物活性化合物封端。傅立叶变换红外分光光度计分析表明存在酚和类黄酮化合物的几个官能团。这些官能团在AgNPs合成中充当还原剂。结论：这些结果表明，生物合成的纳米颗粒在水性条件下将银离子还原为银纳米颗粒，并且形成的AgNP稳定且毒性较小。