This study reports a scalable green electrochemical synthesis of novel biogenic silver nanoparticles colloid (biogenic AgNPs) in large scale up to 5 liters using the bulk silver bar and the green tea leaves (Camellia sinensis) extract (GTE) as reducing agent during the electrochemical process. Under a direct-current voltage source, the biomolecules in GTE can release electrons to promote the reducing process of Ag⁺ to Ag⁰. More interestingly, the formation of the intermediate complex helps to cap on the nanoparticles, which leads to stabilizing AgNPs. The as-synthesized biogenic AgNPs with the size of 34 nm exhibit the outstanding electrochemical properties due to the presence of biomolecules on the biogenic AgNPs surface, which facilitates the effective attaching of AgNPs on the carbon surface of the screen-printed carbon electrode (SPE) through the formation of the strong C-O coordinate bonds between O atom of oxygen functional groups and C atom of SPE. The electrochemical properties of the biogenic AgNPs-modified SPE are enhanced significantly in comparison with bare SPE and pure AgNPs-SPE. The biogenic AgNPs-SPE is applied successfully to the detection of 4-nitrophenol (4-NP). The electrochemical sensor using biogenic AgNPs can reliably detect 4-NP in the linear range from 0.1 to 25 μM with the sensitivity about 6.69 μA μM^-1 cm^-2. The present work reveals, as the greener synthesis method with ultra-large scalable ability, high purity, and excellent electrochemical properties of biogenic AgNPs is very promising for technological applications in high-sensitive electrochemical chemosensors, nanopharmaceuticals, and other fields.

中文翻译：

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新型生物银纳米粒子的可扩展电化学合成及其在水系统中4-硝基苯酚的高灵敏检测中的应用

这项研究报告新颖的生物纳米银颗粒的一个可扩展的绿色电化学合成使用批量银条和绿茶叶（大规模胶体（生物源的AgNPs）5升茶树）提取物（GTE）作为在电化学过程还原剂。在直流电压源的作用下，GTE中的生物分子可以释放电子以促进Ag ⁺还原为Ag ^0的过程。。更有趣的是，中间体复合物的形成有助于覆盖在纳米颗粒上，从而稳定了AgNPs。由于生物分子AgNPs表面上存在生物分子，因此合成后的大小为34 nm的生物AgNPs表现出出色的电化学性能，这有助于AgNPs有效地附着在丝网印刷碳电极（SPE）的碳表面上通过在氧官能团的O原子和SPE的C原子之间形成强CO配位键来实现。与裸露的SPE和纯AgNPs-SPE相比，生物型AgNPs改性的SPE的电化学性能得到了显着提高。生物型AgNPs-SPE已成功应用于4-硝基苯酚（4-NP）的检测。 μ米，大约6.69的灵敏度 μ阿 μ中号^-1厘米^-2。目前的工作表明，作为一种绿色环保的合成方法，具有超大的可扩展能力，高纯度和优异的生物型AgNPs电化学性能，对于在高灵敏度电化学化学传感器，纳米药物和其他领域的技术应用而言，非常有前途。