Gas chromatographic determination of formaldehyde in air using solid-phase microextraction sampling

摘要

The optimization of in situ derivatization and preconcentration of formaldehyde in air using solid phase microextraction with gas chromatographic determination was investigated. A dimethylpolysiloxane coating (7 mu m) solid-phase microextraction needle was used in the final procedure as a support for derivatizing reagents such as 2,4-dinitrophenylhydrazine and acetylacetone. Standard concentrations of formaldehyde in air were obtained using a headspace technique and equilibrium concentrations of formaldehyde in air were calculated using Henry's law. After derivatization on the fiber, the derivative was thermally desorbed in the injector of a gas chromatograph and analyzed using an electron capture detector. A detection limit of 0.17 mg m(-3) was obtained. Calibration was done at 296 K. Reproducibility of the method was 9.6 %. Some real air samples were also analyzed. The method is very convenient and ideal for the rapid determination of formaldehyde in air. [References: 22]