Label-free detection of C-reactive protein using a carbon nanofiber based biosensor.
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 3×3 configuration. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) 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.
NASA Ames Research Center, Moffett Field, CA 94035, USA; Department of Electronics, G. G. M. Science College, Jammu Tawi, 18004, J&K, India.
Rakesh K
RK
Gupta
NASA Ames Research Center, Moffett Field, CA 94035, USA; NASA Johnson Space Center, Houston, TX 77058, USA.
Adaikkappan
A
Periyakaruppan
NASA Ames Research Center, Moffett Field, CA 94035, USA.
M
M
Meyyappan
NASA Ames Research Center, Moffett Field, CA 94035, USA. Electronic address: Jessica.E.Koehne@nasa.gov.
Jessica E
JE
Koehne
D015374:Biosensing Techniques / Q000295:instrumentation*; D002097:C-Reactive Protein / Q000032:analysis*; D002244:Carbon / Q000737:chemistry*; D058266:Dielectric Spectroscopy / Q000295:instrumentation; D004867:Equipment Design; D006801:Humans; D057230:Limit of Detection; D057139:Nanofibers / Q000737:chemistry*
D002244:Carbon; D002097:C-Reactive Protein
Biosensors; C-reactive protein; Carbon nanofibers; Electrical impedance spectroscopy etc.; Nanoelectrode array