A nanocomposite containing Prussian Blue, platinum nanoparticles and polyaniline for multi-amplification of the signal of voltammetric immunosensors: highly sensitive detection of carcinoma antigen 125

作者：Zheng, Yun; Wang, Huiqiang; Ma, Zhanfang^*

来源：Microchimica Acta, 2017, 184(11): 4269-4277.

DOI：10.1007/s00604-017-2470-2

• Tumor marker
• Glassy carbon electrode
• Square wave voltammetry
• Electrochemical biosensor
• Human serum
• Redox species
• Conductive hydrogel
• Catalytic activity
• Chemiluminescent microparticle immunoassay

The authors describe a method for signal amplification of label-free voltammetric immunosensors. A glassy carbon electrode (GCE) was modified with Prussian Blue-platinum nanoparticles (PB-PtNPs) as a redox-active species that gives a strong amperometric signal at 0.18 V (vs. Ag/AgCl). Benefitting from the excellent electrical conductivity and the strong catalytic activity to H2O2, the modified GCE gives a strongly enhanced signal. The PB-PtNPs were incorporated into a polyaniline (PANI) hydrogel to further enhance the signal. The signal response of the PB-PtNP-PANI/GCE is larger by a factor of 7.6 than that of PB-PtNP/GCE. In order to further improve electrical conductivity and immobilize antibody, gold nanoparticles (AuNPs) were deposited on the surface of the PB-PtNP-PANI hydrogel. The AuNP-PB-PtNP-PANI hydrogel nanocomposite on the GCE was used in an immunosensor for the model analyte carcinoma antigen 125 (CA125), a biomarker for epithelial ovarian cancer, by immobilizing the respective antibody on the modified GCE. A linear response found for the 0.01 to 5000 U mL(-1) CA125 concentration range, with a detection limit of 4.4 mU mL(-1) (at an S/N ratio of 3). The electrochemical sensitivity is as high as 119.76 mu A.(U/mL)(-1).cm(-2). The detection of CA125 in human serum showed satisfactory accuracy compared to a commercial chemiluminescent microparticle immunoassay (CMIA).

• 出版日期2017-11
• 单位首都师范大学