|Name||Mr. Arthur Omran|
|Organization||Florida State University Department of Chemistry and Biochemistry|
A Quantitative Assay for Formaldehyde Detection using Orcinol
Arthur P. Omran and Oliver Steinbock
Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306-4390
Colorimetric tests are a quick and efficient way to determine if a chemical is present. One reliable colorimetric method is Bial’s test. Classically Bial’s solution has been used to detect pentose and hexose sugars in solution. Bial’s solution also could be used to identify formaldehyde. We have extended the modern Bial’s test to include formaldehyde in a quantitative fashion. Concentrations of formaldehyde over 1 mM form a brown precipitate that sediments after forming. For a quick and simple detection of high concentrations this precipitate is a good indicator. Below 1 mM no observable precipitate is formed. Using ultraviolet/visible light spectroscopy and fluorescent emission spectroscopy is a reliable way to detect and quantify formaldehyde. The method reliably detects formaldehyde in the millimolar and micromolar ranges of 0.03 mM (0.9 ppm) to 1.8 mM (54 ppm), and 0.6 μM (0.018 ppm) to 20 μM (0.6 ppm). The Environmental Protection Agency uses a standard method of derivatization and ion chromatography to detect formaldehyde. The limit of detection for the EPA’s method is 0.2 μM or 6.02 x10-3 ppm. This is slightly more sensitive than our method. Our method is faster and more affordable. Our method does not require derivatization, or separations. We recommend this method for quick analysis of water samples that may be contaminated with formaldehyde.