Construction of a Sensitive Electrochemiluminescence Resonance Energy Transfer Biosensor and Its Application in Detection of Prostate Specific Antigen in Serum

KeyWord:electrochemiluminescence resonance energy transfer£¨ECL£­RET£©  prostate specific antigen£¨PSA£©  quaternary Cu-Zn-In-S nanocrystals  multi-walled carbon nanotubes£¨MWNTs£©

Abstract:

      The accurate and rapid quantitative detection on cancer biomarkers is of great significance to early diagnosis and prognosis monitoring£¬especially for prostate cancer£¬the most common malignant tumor in male genitourinary system£¬its prostate specific antigen£¨PSA£© is the most important early detection index for blood serum£®Herein£¬an electrochemiluminescence resonance energy transfer immunosensor£¨ECL£­RET£© was constructed for the ultrasensitive detection of PSA in serum£¬with quaternary Cu£­Zn£­In£­S nanocrystals£¨NCs£© as the ECL donor and gold nanostars£¨AuNSs£© as the acceptor£®The immunosensor exhibited a very strong initial ECL signal and a low ECL potential. The multi-walled carbon nanotubes£¨MWNTs£© attached on the substrate not only accelerated the reaction between NCs and S2O2?8 to obtain a high ECL signal£¬but also assembled a large number of antibodies to improve the sensitivity of the sensor as a carrier£®The electrochemical impedance spectroscopy£¨EIS£©? was used to investigate the assembly process£¬and electrochemiluminescence£¨ECL£© was used to study the response to different concentrations of PSA£®The proposed ECL£­RET immunosensor possessed a good analytical performance£¬with a wide linear range of 0.01£­150 ng/mL and a detection limit£¨ S/N = 3£© of 0.03 ng/mL. In addition£¬the ECL£­RET immunosensor was successfully applied to the determination of PSA in human serum samples£¬with relative errors of £­7.2%£­6.0%£¬indicating that the proposed immunosensor is a promising tool for PSA detection in real samples.