The biological synthesis of metal nanoparticles using plant extracts with defined size and morphology is a simple, nontoxic and environmentally friendly method. The present study focused on the synthesis of silver nanoparticles (Ag NPs) by Artemisia annua L. extract as reducing and stabilising agent. The Ag NPs function, as antibacterial agents, is with that they are further used in human therapy. The effects of pH and temperature on the synthesis of NPs were characterized by UV-absorption spectroscopy and shown by surface plasmon resonance (SPR) band at 410 nm. NPs' size and morphology were measured by transmission electron microscopy (TEM) and dynamic light scattering (DLS). TEM images showed that Ag NPs were in a nano-sized range (20-90 nm) and had spherical shape. Our findings demonstrated that lower concentration (100 µg mL-1) of the biogenic Ag NPs exhibited antibacterial activity against Gram-negative Escherichia coli BW 25113 and Gram-positive Enterococcus hirae ATCC 9790.

中文翻译：

---

使用青蒿提取物在纳米颗粒中银离子的生物还原：表征和作为抗菌剂的应用。

使用具有确定的大小和形态的植物提取物生物合成金属纳米颗粒是一种简单，无毒且对环境友好的方法。本研究的重点是用青蒿提取物作为还原剂和稳定剂合成银纳米颗粒（Ag NPs）。Ag NPs作为抗菌剂，具有进一步用于人体治疗的功能。pH和温度对NP合成的影响通过紫外吸收光谱表征，并通过410 nm的表面等离振子共振（SPR）谱带显示。NP的大小和形态通过透射电子显微镜（TEM）和动态光散射（DLS）测量。TEM图像显示Ag NP在纳米范围（20-90nm）内并且具有球形。