Label-free detection of C-reactive protein using a carbon nanofiber based biosensor

Authors

Rakesh K. Gupta, NASA Ames Research Center
Adaikkappan Periyakaruppan, NASA Ames Research Center
M. Meyyappan, NASA Ames Research Center
Jessica E. Koehne, NASA Ames Research CenterFollow

Document Type

Article

Date of this Version

2014

Citation

Biosensors and Bioelectronics 59 (2014) 112-119

Comments

This article is a U.S. government work, and is not subject to copyright in the United States.

Abstract

We report the sensitive detection of C-reactive protein (CRP), a biomarker for cardiac disease, using a carbon nanofiber based biosensor platform. Vertically aligned carbon nanofibers were grown using plasma enhanced chemical vapor deposition to fabricate nanoelectrode arrays in a 3 x 3 configuration. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (ElS) were used for the CRP detection. The CV responses show a 25% reduction in redox current upon the immobilization of anti-CRP on the electrode where as a 30% increase in charge transfer resistance is seen from EIS. Further reduction in redox current and increase in charge transfer resistance result from binding of CRP on anti-CRP immobilized surface, proportional to the concentration of the CRP target. The detection limit of the sensor is found to be ~ 90 pM or ~ 11 ng/ml, which is in the clinically relevant range. Control tests using non-specific myoglobin antigen confirmed the specificity of the present approach.