REMOTE SCANNING ULTRAVIOLET DETECTION FOR CAPILLARY GAS-CHROMATOGRAPHY

A remote flow cell has been interfaced to a scanning uv-visible absorbance detector for the detection of gas chromatography (GC) analytes. The unique optical bench, detection scheme, and thermal control allow low-noise operation at flow cell temperatures of 350-degrees-C. Noise of 1 x 10(-5) a.u. (peak to peak over a 1-min period) and drift at the 1 x 10(-4) a.u./h level facilitate detection of coumarin in the gas phase at 40 pg/s. Flow cell volume was optimized for use with capillary GC columns. An effective band pass of < 3 nm provides spectral resolution which shows solute absorbance fine structure to aid in compound identification.