Article

Electrical detection of protein biomarkers using bioactivated microfluidic channels.

Stanford University Electrical Engineering Department, Stanford, CA 94305, USA.
Lab on a Chip (Impact Factor: 5.75). 06/2009; 9(10):1429-34. DOI: 10.1039/b818872f
Source: PubMed

ABSTRACT Current methods used for analyzing biomarkers involve expensive and time consuming techniques like the Sandwich ELISA which require lengthy incubation times, high reagent costs, and bulky optical equipment. We have developed a technique involving the use of a micro-channel with integrated electrodes, functionalized with receptors specific to target biomarkers. We have applied our biochip to the rapid electrical detection and quantification of target protein biomarkers using protein functionalized micro-channels. We successfully demonstrate detection of anti-hCG antibody, at a concentration of 1 ng ml(-1) and a dynamic range of three orders of magnitude, in less than one hour. We envision the use of this technique in a handheld device for multiplex high throughput analysis using an array of micro-channels for probing various protein biomarkers in clinically relevant samples such as human serum for cancer detection.

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