Mikelashvili Vladimer, Kekutia Shalva, Markhulia Jano, Saneblidze Liana, Maisuradze Nino, Kriechbaum Manfred, Almásy László
Nanocomposites Laboratory, Vladimer Chavchanidze Institute of Cybernetics of the Georgian Technical University, Z. Anjafaridze Str. 5, 0186 Tbilisi, Georgia.
Institute of Inorganic Chemistry, Graz University of Technology, Stremayrgasse 9/5, A-8010 Graz, Austria.
Materials (Basel). 2023 Jan 12;16(2):746. doi: 10.3390/ma16020746.
Chemical co-precipitation from ferrous and ferric salts at a 1:1.9 stoichiometric ratio in NHOH base with ultrasonication (sonolysis) in a low vacuum environment has been used for obtaining colloidal suspensions of FeO nanoparticles coated with citric acid. Before coating, the nanoparticles were processed by electrohydraulic discharges with a high discharge current (several tens of amperes) in a water medium using a pulsed direct current. Magnetite nanoparticles were obtained with an average crystallite diameter D = 25-28 nm as obtained by XRD and particle sizes of 25 nm as measured by small-angle X-ray scattering. Magnetometry showed that all samples were superparamagnetic. The saturation magnetization for the citric acid covered samples after electrohydraulic processing showed higher value (58 emu/g) than for the directly coated samples (50 emu/g). Ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy showed the presence and binding of citric acid to the magnetite surface by chemisorption of carboxylate ions. Hydrodynamic sizes obtained from DLS and zeta potentials were 93 and 115 nm, -26 and -32 mV for the citric acid covered nanoparticles and 226 nm and 21 mV for the bare nanoparticles, respectively. The hydraulic discharge treatment resulted in a higher citric acid coverage and better particle dispersion. The developed method can be used in nanoparticle synthesis for biomedical applications.
在低真空环境中，通过超声处理（声解），以1:1.9的化学计量比在氢氧化铵碱中由亚铁盐和铁盐进行化学共沉淀，已被用于获得涂有柠檬酸的FeO纳米颗粒的胶体悬浮液。在涂层之前，使用脉冲直流电在水介质中通过高放电电流（几十安培）的电液压放电对纳米颗粒进行处理。通过XRD获得的磁铁矿纳米颗粒的平均微晶直径D = 25 - 28 nm，通过小角X射线散射测量的粒径为25 nm。磁强计表明所有样品都是超顺磁性的。电液压处理后，柠檬酸覆盖样品的饱和磁化强度（58 emu/g）高于直接涂层样品（50 emu/g）。紫外可见光谱和傅里叶变换红外光谱表明，通过羧酸根离子的化学吸附，柠檬酸存在于磁铁矿表面并与之结合。通过动态光散射（DLS）获得的流体动力学尺寸和zeta电位，对于柠檬酸覆盖的纳米颗粒分别为93和115 nm、-26和-32 mV，对于裸露的纳米颗粒分别为226 nm和21 mV。液压放电处理导致更高的柠檬酸覆盖率和更好的颗粒分散性。所开发的方法可用于生物医学应用的纳米颗粒合成。
