Immobilized SCM-GFETs. Next, we demonstrated biosensing using the SCM-GFETs. CRP, which is considered a universal biomarker for a variety of diseases, including cardiovascular diseases and disorders, as well as an early indicator of infectious or inflammatory conditions, was used as the target analyte. Figure (a) depicts the schematic of a GFETsig (#1-#24), whose surface was decorated with the QAC, anti-CRP mAb, and BSA blocking, and a GFETref (#31-#54), whose surface was decorated with BSA blocking alone. The time series of ΔVDP in Fig. shows that values of ΔVDP remained relatively constant during the blank sample measurement steps. Conversely, the values of ΔVDP increased during the CRP measurement steps despite a small drift that was not fully compensated by the differential measurements, particularly at the onset of the measurements for each step. Thus, the data for the last 10 min of each step were used to calculate S. A plot of S as a function of CRP concentration, which is presented in Fig. ), demonstrates a monotonic trend. The standard deviation of S for the blank samples (σN) was calculated to be 1.1 mV, resulting in a noise floor (3σN) of 3.3 mV. S surpassed the noise floor at a concentration of 3.8 nM, indicating that the device responded to the CRP.