Miao Juncong, Du Kang, Li Xuan, Xu Xiaoting, Dong Xue, Fang Jinglong, Cao Wei, Wei Qin
Collaborative Innovation Center for Green Chemical Manufacturing and Accurate Detection, Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China.
CECEP&CIECC Environmental Investment Management Co.,Ltd., Beijing, 100034, China.
Biosens Bioelectron. 2021 Jan 1;171:112713. doi: 10.1016/j.bios.2020.112713. Epub 2020 Oct 10.
Procalcitonin (PCT) as a disease marker is of great significance in the early diagnosis of septicemia and pyemia. Biosensor have good prospects for analysis and detection of disease markers, but developing highly sensitive detection methods for detecting PCT remains a daunting task. In this paper, we develop a ratiometric electrochemical immunosensor with Au NPs modified SiO-Fc-COOH complex as matrix and UiO-66 loaded with Toluidine blue (TB) as a marker for quantitative detection of procalcitonin (PCT). The SiO modified by APTES not only has a large specific surface area but also contains abundant amino groups, which can be connected to the electrochemical probe of ferrocenecarboxylic acid (Fc-COOH). UiO-66 has the advantages of large specific surface area, high porosity and adjustable structure, which can adsorb toluidine blue electrochemical probe through electrostatic attraction. Measurement and analysis of the prepared immunosensor by Differential Pulse Voltammetry (DPV) show that the oxidation peak currents of Fc-COOH and TB appear at potentials of 0.30 V and -0.30 V respectively. As the PCT concentration increases, the oxidation peak current of TB increases and the oxidation peak current of Fc-COOH decreases. The ratios (ΔI=ΔI/ΔI) between the double signals could show a certain linear relationship with the concentration of the PCT within a certain range. Under optimal conditions, the linear range of detection obtained by the immunosensor was 1 pg/mL-100 ng/mL and the detection limit was 0.3 pg/mL. In this work, the developed ratiometric electrochemical immunosensor not only provides a simple, reliable and sensitive strategy for quantitative detection of PCT but also provides a useful method for clinical detection of other disease markers.
降钙素原（PCT）作为一种疾病标志物，在败血症和脓血症的早期诊断中具有重要意义。生物传感器在疾病标志物的分析检测方面具有良好的前景，但开发用于检测PCT的高灵敏度检测方法仍然是一项艰巨的任务。本文构建了一种比率型电化学免疫传感器，以金纳米粒子修饰的SiO-Fc-COOH复合物为基质，负载甲苯胺蓝（TB）的UiO-66为标记物，用于降钙素原（PCT）的定量检测。经APTES修饰的SiO不仅具有较大的比表面积，而且含有丰富的氨基，可与二茂铁羧酸（Fc-COOH）电化学探针相连。UiO-66具有比表面积大、孔隙率高和结构可调控等优点，可通过静电吸引吸附甲苯胺蓝电化学探针。采用差分脉冲伏安法（DPV）对制备的免疫传感器进行测量和分析，结果表明Fc-COOH和TB的氧化峰电流分别出现在0.30 V和-0.30 V电位处。随着PCT浓度的增加，TB的氧化峰电流增大，Fc-COOH的氧化峰电流减小。双信号之间的比率（ΔI=ΔI/ΔI）在一定范围内与PCT浓度呈一定的线性关系。在最佳条件下，该免疫传感器的检测线性范围为1 pg/mL-100 ng/mL，检测限为0.3 pg/mL。本研究中构建的比率型电化学免疫传感器不仅为PCT的定量检测提供了一种简单、可靠且灵敏的策略，也为其他疾病标志物的临床检测提供了一种有用的方法。
