Comparison of measurement protocol for biosensors using fiber optic localized surface plasmon resonance sensor

In an immunoassay test, which is a representative analytical method for evaluating the performance of a biosensor, the change of the sensor’s output with respect to the continuous change of the measurement target concentration is represented by a graph and defined as the characteristic curve of the sensor. In most studies using biosensors (disposable or not disposable), the characteristic curve of the sensor is obtained by accumulating and successively changing the concentration of the target using a single sensor (consecutive measurement using a single sensor: CS protocol). However, the CS protocol has an inherent error because the accumulated measurement results for a single sensor that continuously varies with the concentration of the target material are considered as the sensor’s output at each concentration level. In this paper, we obtain the characteristic curve of the sensor by measuring the different concentrations of the target using different sensors (separate measurement using the individual sensor: SI protocol). By comparing this characteristic curve with the characteristic curve obtained using the CS protocol, we prove that the widely used method based on CS protocol is inaccurate as a measurement protocol for biosensors.