Detection of CO concentration by using SnO2 SPR apparatus and common-path heterodyne interferometer

Abstract

A conception by using integration of chemical microsensors and surface plasmon resonance (SPR) is proposed to sense carbon monoxide (CO). The research is based on the common-path heterodyne interferometer which contains nondestructive, high-sensitivity, and high accuracy optical sensing system and combines the tin dioxide which is chemical stability to sense CO as analyte of SPR. Under this configuration, the method can measure tiny phase differences for SnO2 with different CO concentration. The minimum resolution of gas concentration is verified with a best value of 0.0207ppm occurring in pH 9. © 2013 Springer Science+Business Media New York.