Electrochemical DNA Biosensor Based on thiolated-MWCNTs modified glassy carbon electrode for Determination of Protein and Hemoglobin in Urine at Exercise Training Levels

Abstract

The synthesis of conjugated glycated hemoglobin (gHb)-DNA on thiolated-MWCNTs modified glassy carbon electrode (gHb-DNA/MWCNTs/GCE) and application as a sensor of nuclear matrix protein 22 (NMP22) and hemoglobin (protein inside red blood cells) in urine specimens at different levels of exercise training was studied. Surface analysis of functionalized MWCNTs/GCE using SEM analysis revealed that formation entangled f-MWCNT network can act as a porous conductive substrate for immobilization DNA. Electrochemical analyses were performed using DPV and amperometry. The electrochemical results showed the simultaneous determination of Hb and NMP22 with higher stability and sensitivity on gHb-DNA/MWCNTs/GCE toward f-MWCNTs/GCE,gHb-DNA/GCE. The amperometric analyses of gHb-DNA/MWCNTs/GCE showed that the linear range, limit of detection and the sensitivity for determination NMP22 were obtained 1 to 100μg/mL, 0.007ng/mL and 10.4146μA/μg mL−1, respectively. The linear range, the limit of detection, and the sensitivity for determination of NMP22 were obtained 1 to 100μg/mL, 0.005ng/mL and 14.0865μA/μg mL−1, respectively. The selectivity and practical ability of gHb-DNA/MWCNTs/GCE for determination of Hb and NMP22 were examined in presence of various interfering species and prepared clinical urine specimens. The results indicated a selective, reliable, and accurate response of gHb-DNA/MWCNTs/GCE as electrochemical Hb and NMP22 sensors.