A simple fluorometric method for the determination of sulfur dioxide in ambient air with a passive sampler

A simple and rapid fluorescence detection method was used for the determination of sulfur dioxide (SO(2)) in ambient air collected by a passive sampler. Gaseous SO(2) was absorbed as sulfite ions into an absorbing solution of triethanolamine (TEA) contained in an adsorbent sheet and reacted with N-(9-acridinyl)maleimide (NAM), which was used as a fluorescent reagent. TEA was also used as a buffer solution in this study. The calibration curve of SO(2) showed a linear correlation R(2)=0.992, and the relative standard deviation (RSD) was 2.4% for 50 ppb SO(2) with six repeated measurements. It was satisfactory to apply this method to determine the SO(2) level for simultaneous multipoint monitoring.