An Ultra Sensitive Electrochemical Determination of Trypsin Based on Laser Reduced Graphene Oxide Annular Sensor in Biological Product

In this study, a novel laser reduced graphene oxide annular sensor was fabricated for electrochemical determination of trypsin in biological real samples. The annular sensor was fabricated by using a green laser diode under optimal conditions on a flexible substrate. The sensor surface was characterized by using a scan electron microscope (SEM) and Raman spectroscopy (RS). The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) showed the higher redox current and higher electrical conductivity of the sensor. Trypsin determination has been optimized in terms of deposition time, pH, and reproducibility. Under the optimization conditions, the electrochemical determination of trypsin, the calibration curve, shows a linear range between 0.02-0.10 mg/L, and with a limit of detection (LOD) of 0.01 mg/L. We have successfully used the laser-induced graphene oxide sensor fabricated in this study to determine trypsin concentrations in biological products.