目的 使用单味药渣绿色合成纳米银，研究生物合成参数对纳米银生成、粒径及多分散性的影响；研究合成的纳米银理化性质、抗癌活性及作用机制。方法 使用肿节风药渣在超声条件下合成纳米银，紫外可见光谱监测纳米银生成和生长，激光粒度仪和透射电镜表征纳米银的组成、粒径、分散性、表面性质和形貌，MTT法检测抗癌活性，流式细胞技术测纳米银内吞作用，2',7'-二氯荧光素-二乙酸酯染色法检测活性氧物质。结果 pH 7.0、肿节风药渣提取液-AgNO₃ 2∶1、反应时间4.0 h时生成效率最高；pH 10.0、物料比1∶1或pH 7.0、物料比2∶1时能获得粒径为34 nm左右的纳米银，但碱性条件影响纳米银的分散性；物料比1∶1时可获得分散性最好的纳米银，多分散指数（polydispersity index，PDI）为0.20。pH 7.0、物料比2∶1、反应时间2.0 h时生成的纳米银呈近球形，粒径在20～30 nm，以单分散形式存在，为六方晶型结构，表面带负电荷，ζ电势−22.2 mV，1个月内保持稳定，对人肝癌HepG2细胞的半数抑制浓度（IC₅₀）为44.2 μg/mL，该方法合成的纳米银可被细胞摄入并在细胞内产生活性氧物质。结论 使用单味中药肿节风药渣可绿色合成纳米银，生物合成参数对纳米银形成、粒径及多分散性影响较大；制得的纳米银有强体外抗癌活性，可能通过产生活性氧物质破坏细胞组织或DNA等杀死癌细胞。

Objective To develop a novel method to biosynthesize silver nanoparticles (AgNPs) by using the extract of single Chinese herbal waste to overcome the difficulty in obtaining raw materials. To evaluate the effect of biosynthesis parameters on the formation of AgNPs, average size and polydispersity, and investigating the anticancer activity. Methods The formation of AgNPs was monitored by UV-visible spectroscopy; The average size, polydispersity, surface and morphology features of AgNPs were characterized by laser granularity analyzer and transmission electron microscopy; The anticancer activity of AgNPs were evaluated by MTT assay. The internalization of AgNPs inside HepG2 cancer cell line was determined by flow cytometric analysis. Reactive oxygen species (ROS) were measured by 2',7'-dichlorofluorescein-diacetate staining. Results By using the extract of Glabrous sarcandra herb residues, AgNPs could be prepared at ambient temperature under ultrasonic radiation. Biosynthesis of AgNPs- AgNO₃ 2∶1 at pH 7.0 would have the maximum efficiency. The AgNPs with small average size could be obtained at pH 10.0, extract-AgNO₃ 1∶1 or pH 7.0, extract-AgNO₃ 2∶1. But the AgNPs with superior polydispersity could be prepared under extract- AgNO₃ 2∶1. TEM, HRTEM and SAED characterization revealed that AgNPs (pH 7.0; material proportion 2∶1; 2.0 h) had a hexagonal structure, spherical shape with an average size of (34.0 ±0.7) nm and existed in monodispersed form. The ζ potential of as-prepared AgNPs was −22.2 mV. The biosynthesized AgNPs displayed potent toxic effects against HepG2 cancer cell line with IC₅₀ 44.2 μg/mL. The AgNPs as-prepared revealed significant uptake into cancer cell and could produce reactive oxygen species in HepG2 cancer cell lines. Conclusion The extract of G. sarcandra residues could be used to synthesize AgNPs at ambient temperature; The biosynthesis parameters have significant effects on the generation, average size and polydispersity of AgNPs; The biosynthesized AgNPs have potent anticancer activity, which may originate from the formation of ROS.

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国家自然科学基金资助项目(22103007);陕西省高校科协青年人才托举计划(20190307);陕西省教育厅重点科研计划(21JY009);陕西省重点研发项目(2019SF-082);陕西省教育厅自然科学研究项目(19JK0233)