Velasco-Rodriguez Brenda, Soltero-Martínez J Félix, Rosales-Rivera Luis Carlos, Macías-Balleza Emma Rebeca, Landázuri Gabriel, Larios-Durán Erika Roxana
Departamento de Ingeniería Química, Universidad de Guadalajara, CUCEI, Blvd. M. García Barragán #1451, C.P., 44430 Guadalajara, Jalisco, México.
ACS Omega. 2020 Jul 8;5(28):17347-17355. doi: 10.1021/acsomega.0c01704. eCollection 2020 Jul 21.
The interactions of proteins and other molecules and their adsorption onto substrates is a fascinating topic that has been applied to surface technologies, biosensors, corrosion studies, biotechnologies, and other fields. The success of these applications requires a previous characterization using some analytical techniques that, ordinarily, are not electrochemical. This work proposes analyzing the variation of the double-layer capacitance obtained through impedance electrochemical spectroscopy as an alternative strategy to show evidence of the interactions between proteins and triblock copolymers. The proposal is supported through the study of the interaction and adsorption of bovine serum albumin (BSA) and a commercial triblock copolymer (P103) in phosphate buffer on a gold electrode. The double-layer capacitance and the apparent interface thickness vs polarization potential curves as well as the potential of zero charge for pure P103 (0.6 wt %, corresponding to 6 g L), pure BSA (3 mg mL), and P103-BSA solutions (0.6 wt % and 3 mg mL, respectively) are sensitive enough to show not only the interaction and the adsorption of the species but also the polarization potential where these interactions are taking place. A qualitative and quantitative analysis concerning the double-layer capacitance behavior is given. The significance and impact of this work is also presented.
蛋白质与其他分子的相互作用及其在基底上的吸附是一个引人入胜的课题，已应用于表面技术、生物传感器、腐蚀研究、生物技术及其他领域。这些应用的成功需要使用一些通常并非电化学的分析技术进行前期表征。本文提出通过阻抗电化学光谱分析双层电容的变化，作为一种显示蛋白质与三嵌段共聚物之间相互作用证据的替代策略。该提议通过研究牛血清白蛋白（BSA）与一种商用三嵌段共聚物（P103）在磷酸盐缓冲液中于金电极上的相互作用和吸附来支持。双层电容和表观界面厚度与极化电位曲线以及纯P103（0.6 wt%，相当于6 g/L）、纯BSA（3 mg/mL）和P103 - BSA溶液（分别为0.6 wt%和3 mg/mL）的零电荷电位足够灵敏，不仅能显示物种的相互作用和吸附，还能显示这些相互作用发生的极化电位。给出了关于双层电容行为的定性和定量分析。还阐述了这项工作的意义和影响。
