A SPR biosensor based on signal amplification using antibody-QD conjugates for quantitative determination of multiple tumor markers.
The detection of tumor markers is very important in early cancer diagnosis; however, tumor markers are usually present at very low concentrations, especially in the early stages of tumor development. Surface plasmon resonance (SPR) is widely used to detect biomolecular interactions; it has inherent advantages of being high-throughput, real-time, and label-free technique. However, its sensitivity needs essential improvement for practical applications. In this study, we developed a signal amplification strategy using antibody-quantum dot (QD) conjugates for the sensitive and quantitative detection of α-fetoprotein (AFP), carcinoembryonic antigen (CEA) and cytokeratin fragment 21-1 (CYFRA 21-1) in clinical samples. The use of a dual signal amplification strategy using AuNP-antibody and antibody-QD conjugates increased the signal amplification by 50-folds. The constructed SPR biosensor showed a detection limit as low as 0.1 ng/mL for AFP, CEA, and CYFRA 21-1. Moreover, the results obtained using this SPR biosensor were consistent with those obtained using the electrochemiluminescence method. Thus, the constructed SPR biosensor provides a highly sensitive and specific approach for the detection of tumor markers. This SPR biosensor can be expected to be readily applied for the detection of other tumor markers and can offer a potentially powerful solution for tumor screening.
Department of Laboratory Medicine, Southwest Hospital, the Third Military Medical University, Chongqing 400038, China.|Chongqing Communication Institute, Chongqing 400035, China.
Huan
H
Wang
Department of Geriatrics, Southwest Hospital, the Third Military Medical University, Chongqing 400038, China.
Xiaomei
X
Wang
Department of Laboratory Medicine, Southwest Hospital, the Third Military Medical University, Chongqing 400038, China.
Jue
J
Wang
Department of Laboratory Medicine, Southwest Hospital, the Third Military Medical University, Chongqing 400038, China.
Weiling
W
Fu
Department of Laboratory Medicine, Southwest Hospital, the Third Military Medical University, Chongqing 400038, China.
Chunyan
C
Yao
D000951:Antigens, Neoplasm / Q000032:analysis; D014408:Biomarkers, Tumor / Q000032:analysis*; D002272:Carcinoembryonic Antigen / Q000032:analysis; D006801:Humans; D053539:Keratin-19 / Q000032:analysis; D057230:Limit of Detection; D009369:Neoplasms / Q000175:diagnosis*; D045663:Quantum Dots; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods*; D000509:alpha-Fetoproteins / Q000032:analysis
C097353:AFP protein, human; D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D053539:Keratin-19; D000509:alpha-Fetoproteins; C102012:antigen CYFRA21.1