In this study, we design a theoretical model of glucose concentration sensor using the pole effect of the PT-symmetric structure. Unlike the traditional sensor, the designed model does not use spectrum positions as the sensing mechanism but uses transmittance detection as the sensing method. The new sensing mechanism has high precision and sensitivity. Although our model is for blood glucose sensing, it can be extended to general biomaterial sensing, including sensing various diseased cells. Therefore, this study provides a new universal method for biosensors.