One step in-situ synthesis of amine functionalized graphene for immunosensing of cardiac marker cTnI

2-Aminobenzyl amine (2-ABA) functionalized graphene is proposed for the ultrasensitive immunosensing of Cardiac Troponin I (cTnI). 2-ABA was electrochemically polymerized on the graphene decorated interdigitated electrode to obtain the amine functionalized graphene (f-GN). The f-GN electrode was then modified with monoclonal anti-cTnI antibodies via Schiff reaction based chemistry. Detailed characteristics of the processes involved and the finally developed antibody conjugated f-GN interdigitated electrode have been studied. The above micro-device was used in a drain source configuration for the sensing of cTnI. A wide dynamic linear range of antigen detection (0.01-1 ng/mL) is achieved with the limit of detection of 0.01 ng/mL. The utility of the proposed sensing technique is demonstrated by successfully testing the antigen concentration in spiked serum samples.