An integrated electrochemical device based on immunochromatographic test strip and enzyme labels for sensitive detection of disease-related biomarkers

Department of Chemistry and Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian Province, China.
Talanta (Impact Factor: 3.55). 05/2012; 94:58-64. DOI: 10.1016/j.talanta.2012.02.046
Source: PubMed


A novel electrochemical biosensing device that integrates an immunochromatographic test strip and a screen-printed electrode (SPE) connected to a portable electrochemical analyzer was presented for rapid, sensitive, and quantitative detection of disease-related biomarker in human blood samples. The principle of the sensor is based on sandwich immunoreactions between a biomarker and a pair of its antibodies on the test strip, followed by highly sensitive square-wave voltammetry (SWV) detection. Horseradish peroxidase (HRP) was used as a signal reporter for electrochemical readout. Hepatitis B surface antigen (HBsAg) was employed as a model protein biomarker to demonstrate the analytical performance of the sensor in this study. Some critical parameters governing the performance of the sensor were investigated in detail. Under optimal conditions, this sensor was capable of detecting a minimum of 0.3 ng mL(-1) (S/N=3) HBsAg with a wide linear concentration range from 1 to 500 ng mL(-1). The sensor was further utilized to detect HBsAg spiked in human plasma with an average recovery of 91.3%. In comparison, a colorimetric immunochromatographic test strip assay (ITSA) was also conducted. The result shows that the SWV detection in the electrochemical sensor is much more sensitive for the quantitative determination of HBsAg than the colorimetric detection, indicating that such a sensor is a promising platform for rapid and sensitive point-of-care testing/screening of disease-related biomarkers in a large population.

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Available from: Yuehe Lin, Apr 21, 2015
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    • "Replacement of conventional electrochemical cells by screen printed electrodes (SPE) connected with portable potentiostats is a main trend in the shift of lab electrochemical equipments to handheld field analyzers [15] [16]. The SPE system can be considered as a disposable electrochemical cell, which reduces the required sample volume, simplifies the apparatus and makes the point-of-care testing easy to handle and cost effective [17] [18] [19]. "
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    • "Screen printed electrode (SPE) has improved continuously over past few decades, especially in terms of the printing material. With its merits such as the output linearity, low power requirement, quick response, high sensitivity, simple operation, and low cost, SPE has attracted increasing interest in the field of biosensor (Galandová et al. 2009; Ping et al. 2012; Zou et al. 2012). "
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