Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University, Nanjing, 211198, China.
Faculty of Medicine & Health Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom.
Ultrason Sonochem. 2021 May;73:105485. doi: 10.1016/j.ultsonch.2021.105485. Epub 2021 Feb 3.
Due to the high reactivity of Ag and uncontrolled growth process, the AgNPs produced by conventional Lee-Meisel method always exhibited larger particle size (30-200 nm) and polydisperse morphology (including spherical, triangular, and rod-like shape). An ultrasound-intensified Lee-Meisel (UILM) method is developed in this study to environmental-friendly and controllable synthesize monodisperse spherical AgNPs (~3.7 nm). Effects of Ag:citrate ratio (1:3 or 5:4), ultrasound power (300 to 1200 W) and reaction time (4 to 24 min) on the physical-chemical properties of AgNPs are investigated systematically. The transmission electron microscope (TEM) images, UV-Vis spectra, average particle size, zeta potential and pH value all demonstrate that crystallization and digestive ripening processes are facilitated in the presence of ultrasound irradiation. Therefore, both chemical reaction rate and mass transfer rate are enhanced to accelerate primary nucleation and inhibit uncontrolled particle growth, leading to the formation of monodisperse spherical AgNPs. Moreover, a machine learning approach - Decision Tree Regressor in conjunction with Shapley value analysis reveal the concentration of reactants is a more important feature affecting the particle.
由于 Ag 的高反应性和不可控的生长过程，传统的 Lee-Meisel 法制备的 AgNPs 通常表现出较大的粒径（30-200nm）和多分散的形态（包括球形、三角形和棒状）。本研究开发了一种超声强化 Lee-Meisel（UILM）方法，以环保和可控的方式合成单分散的球形 AgNPs（~3.7nm）。系统研究了 Ag:柠檬酸盐比（1:3 或 5:4）、超声功率（300-1200W）和反应时间（4-24min）对 AgNPs 物理化学性质的影响。透射电子显微镜（TEM）图像、紫外-可见光谱、平均粒径、Zeta 电位和 pH 值均表明，超声辐照有助于促进结晶和消化陈化过程。因此，化学反应速率和传质速率都得到了提高，从而加速了初级成核并抑制了不可控的颗粒生长，形成了单分散的球形 AgNPs。此外，机器学习方法-决策树回归器结合 Shapley 值分析表明，反应物的浓度是影响颗粒的更重要特征。
