Title
Sensitive Bioanalysis Based on in-Situ Droplet Anodic Stripping Voltammetric Detection of CdS Quantum Dots Label after Enhanced Cathodic Preconcentration.
Abstract
We report a protocol of CdS-labeled sandwich-type amperometric bioanalysis with high sensitivity, on the basis of simultaneous chemical-dissolution/cathodic-enrichment of the CdS quantum dot biolabel and anodic stripping voltammetry (ASV) detection of Cd directly on the bioelectrode. We added a microliter droplet of 0.1 M aqueous HNO3 to dissolve CdS on the bioelectrode and simultaneously achieved the potentiostatic cathodic preconcentration of Cd by starting the potentiostatic operation before HNO3 addition, which can largely increase the ASV signal. Our protocol was used for immunoanalysis and aptamer-based bioanalysis of several proteins, giving limits of detection of 4.5 fgmL(-1) for human immunoglobulin G, 3.0 fgmL(-1) for human carcinoembryonic antigen (CEA), 4.9 fgmL(-1) for human -fetoprotein (AFP), and 0.9 fM for thrombin, which are better than many reported results. The simultaneous and sensitive analysis of CEA and AFP at two screen-printed carbon electrodes was also conducted by our protocol.
Year
DOI
Venue
2016
10.3390/s16091342
SENSORS
Keywords
Field
DocType
immunoelectrode,aptamer-electrode,screen-printed carbon electrodes,CdS quantum dot-labeled amperometric bioanalysis,signal amplification
Detection limit,Bioanalysis,Analytical chemistry,Anodic stripping voltammetry,Amperometry,Chemistry,Stripping (chemistry),Chromatography,Quantum dot,Electrode,Aqueous solution
Journal
Volume
Issue
ISSN
16
9.0
1424-8220
Citations 
PageRank 
References 
0
0.34
0
Authors
3
Name
Order
Citations
PageRank
Xiaoli Qin100.34
Linchun Wang200.34
Qingji Xie301.35