Molecules 2013, 18(10), 12675-12686; doi:10.3390/molecules181012675
Article

Electrochemical Enzyme-Linked Immunosorbent Assay (ELISA) for α-Fetoprotein Based on Glucose Detection with Multienzyme-Nanoparticle Amplification

1 Department of Laboratory Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong, China 2 Research Center of Clinical Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong, China 3 The State Key Laboratory Base of Novel Functional Materials and Preparation Science, Faculty of Material Science and Chemical Engineering of Ningbo University, Ningbo 315211, China These authors contributed equally to this work.
* Authors to whom correspondence should be addressed.
Received: 2 August 2013; in revised form: 7 October 2013 / Accepted: 10 October 2013 / Published: 14 October 2013
PDF Full-text Download PDF Full-Text [963 KB, uploaded 14 October 2013 09:31 CEST]
Abstract: Since glucose biosensors are one of the most popular and widely used point-of-care testing devices, a novel electrochemical enzyme-linked immunosorbent assay (ELISA) for protein biomarkers has been developed based on a glucose detection strategy. In this study, α-fetoprotein (AFP) was used as the target protein. An electrochemical ELISA system was constructed using anti-AFP antibodies immobilized on microwell plates as the capture antibody (Ab1) and multi-label bioconjugates as signal tracer. The bioconjugates were synthesized by attaching glucoamylase and the secondary anti-AFP antibodies (Ab2) to gold nanoparticles (AuNPs). After formation of the sandwich complex, the Ab2-glucoamylase-AuNPs conjugates converted starch into glucose in the presence of AFP. The concentration of AFP can be calculated based on the linear relation between AFP and glucose, the concentration of which can be detected by the glucose biosensor. When the AFP concentration ranged from 0.05 to 100 ng/mL, a linear calibration plot (i (µA) = 13.62033 − 2.86252 logCAFP (ng/mL), r = 0.99886) with a detection limit of 0.02 ng/mL was obtained under optimal conditions. The electrochemical ELISA developed in this work shows acceptable stability and reproducibility, and the assay for AFP spiked in human serum also shows good recovery (97.0%–104%). This new method could be applied for detecting any protein biomarker with the corresponding antibodies.
Keywords: glucoamylase; glucose biosensor; electrochemical enzyme-linked immunosorbent assay; starch; gold nanoparticles

Article Statistics

Load and display the download statistics.

Citations to this Article

Cite This Article

MDPI and ACS Style

Liu, Q.-L.; Yan, X.-H.; Yin, X.-M.; Situ, B.; Zhou, H.-K.; Lin, L.; Li, B.; Gan, N.; Zheng, L. Electrochemical Enzyme-Linked Immunosorbent Assay (ELISA) for α-Fetoprotein Based on Glucose Detection with Multienzyme-Nanoparticle Amplification. Molecules 2013, 18, 12675-12686.

AMA Style

Liu Q-L, Yan X-H, Yin X-M, Situ B, Zhou H-K, Lin L, Li B, Gan N, Zheng L. Electrochemical Enzyme-Linked Immunosorbent Assay (ELISA) for α-Fetoprotein Based on Glucose Detection with Multienzyme-Nanoparticle Amplification. Molecules. 2013; 18(10):12675-12686.

Chicago/Turabian Style

Liu, Qin-Lan; Yan, Xiao-Hui; Yin, Xiao-Mao; Situ, Bo; Zhou, Han-Kun; Lin, Li; Li, Bo; Gan, Ning; Zheng, Lei. 2013. "Electrochemical Enzyme-Linked Immunosorbent Assay (ELISA) for α-Fetoprotein Based on Glucose Detection with Multienzyme-Nanoparticle Amplification." Molecules 18, no. 10: 12675-12686.

Molecules EISSN 1420-3049 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert