A fluorometry based gas analyzer was developed for the detection of atmospheric formaldehyde for field sampling. Formaldehyde was collected using a diffusion scrubber containing a permeable NafionRTM tube inside ¼ inch TeflonRTM tubing with dilute sulfuric acid as a scrubbing solution. The formaldehyde was mixed with 0.65 M ammonium acetate and 2,4-pentanedione to produce the fluorescent derivative 3,5 diacetyl-1,4 dihydrolutidine (DDL). When excited by 405 nm light, the DDL was quantified by fluorescence detection with peak emission near 510 nm. A custom software solution was developed for instrument control and measurement of fluorescence signals and improvement of signal to noise ratios. The combination of hardware and software components produced and instrument capable of detecting formaldehyde concentrations above 1.22 ppbv in one minute intervals.
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