Determination of formaldehyde by ion exclusion and ion exchange separation with amperometric detection
A method has been developed for determination of formaldehyde in air sample extracts by ion exclusion and ion exchange separation followed by amperometric detection. Optimum eluant compositions and separation columns for the best separation have been determined, as well as the optimum working electrode, electrolytes, and applied potentials for the best detection. An internal standardization was used to correct for detector drift. An interference study was performed for organic acids, other aldehydes, and alcohols. Using impingers containing aqueous bisulfite solution for collection, a side by side comparison study with the 2,4-DNPH method (also using impingers) was conducted. The detection limit of the method is 1 ng (in solution). The method has been used to determine formaldehyde concentrations in air on the UNLV campus. The method is also potentially applicable to biological and food sample analysis.