Paradowska Ewa, Arkusz Katarzyna, Pijanowska Dorota G
Department of Biomedical Engineering, Faculty of Mechanical Engineering, University of Zielona Gora, Prof. Zygmunta Szafrana 4 Street, 65-516 Zielona Gora, Poland.
Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Ks. Trojdena 4 Street, 02-109 Warszawa, Poland.
Materials (Basel). 2020 Sep 25;13(19):4269. doi: 10.3390/ma13194269.
The increasing interest of attachment of gold nanoparticles (AuNPs) on titanium dioxide nanotubes (TNTs) has been devoted to obtaining tremendous properties suitable for biosensor applications. Achieving precise control of the attachment and shape of AuNPs by methods described in the literature are far from satisfactory. This work shows the comparison of physical adsorption (PA), cyclic voltammetry (CV) and chronoamperometry (CA) methods and the parameters of these methods on TNTs properties. The structural, chemical, phase and electrochemical characterizations of TNTs, Au/TNTs, AuNPs/TNTs are carried out using scanning electron microscopy (SEM), electrochemical impedance spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy. The use of PA methods does not allow the deposition of AuNPs on TNTs. CV allows easily obtaining spherical nanoparticles, for which the diameter increases from 20.3 ± 2.9 nm to 182.3 ± 51.7 nm as a concentration of tetrachloroauric acid solution increase from 0.1 mM to 10 mM. Increasing the AuNPs deposition time in the CA method increases the amount of gold, but the AuNPs diameter does not change (35.0 ± 5 nm). Importantly, the CA method also causes the dissolution of the nanotubes layer from 1000 ± 10.0 nm to 823 ± 15.3 nm. Modification of titanium dioxide nanotubes with gold nanoparticles improved the electron transfer and increased the corrosion resistance, as well as promoted the protein adsorption. Importantly, after the deposition of bovine serum albumin, an almost 5.5-fold (324%) increase in real impedance, compared to TNTs (59%) was observed. We found that the Au nanoparticles-especially those with smaller diameter-promoted the stability of bovine serum albumin binding to the TNTs platform. It confirms that the modification of TNTs with gold nanoparticles allows the development of the best platform for biosensing applications.
人们对将金纳米颗粒（AuNPs）附着在二氧化钛纳米管（TNTs）上的兴趣与日俱增，致力于获得适用于生物传感器应用的卓越性能。通过文献中描述的方法实现对AuNPs附着和形状的精确控制远不能令人满意。这项工作展示了物理吸附（PA）、循环伏安法（CV）和计时电流法（CA）方法的比较以及这些方法对TNTs性能的参数。使用扫描电子显微镜（SEM）、电化学阻抗谱、X射线衍射、X射线光电子能谱对TNTs、Au/TNTs、AuNPs/TNTs进行结构、化学、相和电化学表征。PA方法无法使AuNPs沉积在TNTs上。CV能够轻松获得球形纳米颗粒，随着四氯金酸溶液浓度从0.1 mM增加到10 mM，其直径从20.3±2.9 nm增大到182.3±51.7 nm。在CA方法中增加AuNPs沉积时间会增加金的量，但AuNPs直径不变（35.0±5 nm）。重要的是，CA方法还会导致纳米管层从1000±10.0 nm溶解到823±15.3 nm。用金纳米颗粒修饰二氧化钛纳米管改善了电子转移，提高了耐腐蚀性，并促进了蛋白质吸附。重要的是，在沉积牛血清白蛋白后，与TNTs（59%）相比，实测阻抗增加了近5.5倍（324%）。我们发现金纳米颗粒——尤其是那些直径较小的——促进了牛血清白蛋白与TNTs平台结合的稳定性。这证实了用金纳米颗粒修饰TNTs能够开发出用于生物传感应用的最佳平台。
