The derivatization of formaldehyde with 2,4-dinitrophenylhydrazine and the extraction of the product formalhydrazone is studied. The determination is carried out by HPLC. Applying a cryogenic sampling technique and a sampling volume of 300 l of air the detection limit of formaldehyde in air is 30 pptv and this is suitable for measurements of formaldehyde in the atmosphere.
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