A label-free electrochemical immnunosensor based on signal magnification of oxygen reduction reaction catalyzed by uniform PtCo nanodendrites for highly sensitive detection of carbohydrate antigen 15-3

• Published in: Analytica chimica acta Vol. 1176; p. 338750
• Main Authors: Ge, Xin-Yue, Feng, Yi-Ge, Cen, Shi-Yun, Wang, Ai-Jun, Mei, Li-Ping, Luo, Xiliang, Feng, Jiu-Ju
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2021
• Subjects: Carbohydrate antigen 15-3; l-Carnosine; Label-free immunosensor; Oxygen reduction reaction; Platinum-cobalt nanodendrites; Carbohydrate antigen 15-3; Label-free immunosensor; Platinum-cobalt nanodendrites; l-Carnosine; Oxygen reduction reaction
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2021.338750

Developing a highly sensitive immunoassay for tumor biomarkers is particularly important in bioanalysis and early disease diagnosis. In this work, a simple one-pot solvothermal method was developed for controllable synthesis of well-dispersed PtCo alloyed nanodendrites (PtCo NDs) by using l-carnosine as the co-structure-directing agent. The PtCo NDs had a large specific surface area and provided abundant active sites available for electrocatalytic oxygen reduction reaction (ORR). Based on the highly enhanced currents of the ORR, a novel label-free electrochemical immunosensor was fabricated for highly sensitive assay of carbohydrate antigen 15–3 (CA15-3). The sensor showed a wide linear range of 0.1–200 U mL−1 and a low limit of detection (LOD) down to 0.0114 U mL−1 (S/N = 3), in turn exploring its application to diluted human serum samples with satisfactory results. This study provides a feasible platform for monitoring other tumor markers in clinical diagnosis. [Display omitted] •Uniform PtCo NDs were prepared by a one-pot solvothermal method.•l-Carnosine acted as the co-structure-directing agent for the dendritic structures.•PtCo NDs had large specific surface area and highly catalytic activity for ORR.•The highly enhanced ORR currents were used for constructing the immnunosensor.•The immnunosensor was employed for ultrasensitive detection of CA15-3.