Determination of the Minimum Detectability of Surface Plasmon Resonance Devices by Using the 3σ Rule

Abstract

Surface plasmon resonance (SPR) devices are known to be able to detect traces of chemicals and can, therefore, be applied to a variety of applications. However, in order to define the sensitivity of such a device, one must obtain its minimum detectability. Nevertheless, the standard way to define the lower limit of detectability of an SPR device has not yet been established. In this paper, we propose a method to define the minimum detectability of SPR devices based on the 3σ rule. We measured the response of an SPR device by varying the concentrations of a single neutral analyte (ethylene glycol in deionized water). Then, we successfully obtained its lower limit of detectability, based on the measured data and the 3σ rule. Our method provides a standardized way to easily evaluate the quality of SPR devices.