SODIUM AND POTASSIUM SENSORS BASED ON SEPARATED EXTENDED GATE FIELD EFFECT TRANSISTOR 

[[abstract]]A double potassium and sodium ions sensor based on separated extended gate field effect transistor (SEGFET) and a new entrapment method are proposed in this study. Having high sensitivity, reproducibility, and a simple manufacturing process, the sensors are quickly able to supply information and detect human blood within an abnormal range. The sensing membranes were fabricated using a Poly(vinyl chloride) carboxylated (PVC-COOH) matrix; sodium ionophore (B12C4) or potassium ionophore (valinomycin). The sensitivity of ion-selective biosensors is 42.55 mV/decade for Na(+) between 1 M and 10(-7) M, 42.75 mV/decade for K(+) between 1 M and 10(-6) M.[[note]]SC