Porous graphene based electrochemical immunosensor using Cu 3 (BTC) 2 metal-organic framework as nonenzymatic label

• Published in: Talanta (Oxford) Vol. 217; p. 121042
• Main Authors: Liu, Xiaobang, Yue, Ting, Qi, Kai, Qiu, Yubing, Guo, Xingpeng
• Format: Journal Article
• Language: English
• Published: Netherlands 01.09.2020
• Subjects: Antibodies - chemistry; Biomarkers, Tumor - analysis; Biosensing Techniques; Electrochemical Techniques; Graphite - chemistry; Humans; Hydrogen Peroxide - chemistry; Immunoassay; Metal-Organic Frameworks - chemistry; Molecular Structure; Particle Size; Porosity; Prostate-Specific Antigen - analysis; Surface Properties; Cancer biomarkers; Graphene; Nonenzymatic labels; Immunosensors; Metal-organic frameworks

An electrochemical immunosensor for highly sensitive detection of cancer biomarkers has been developed based on the combination of a sensing platform of polydopamine modified porous graphene and a nonenzymatic label of metal-organic framework (MOF) conjugated secondary antibody. This approach achieves a wide range of linear response from 0.1 to 10 ng/mL, low detection limit of 0.025 ng/mL (at a signal to noise ratio of 3), good reproducibility and selectivity for the detection of prostate specific antigen (PSA) as a model analyte. The high performance of the immunosensor is attributed to the high surface area from porous graphene and the strong adhesion of polydopamine, allowing a high load of the primary antibody of PSA, as well as the highly electrocatalytic activity of the Cu (BTC) (BTC = benzene-1,3,5-tricarboxylic acid) MOF toward H O to provide greatly amplified sensitivity. In this respect, the MOF-based nonenzymatic label shows promising application for the point-of-care detection of different cancer biomarkers in clinical diagnostics.