Biochemistry Method: Simultaneous determination of formaldehyde and methyl tert-buthyl ether in environmental and human biological matrices using static headspace gas chromatography mass spectrometry

The present study describes a method based on static headspace extraction (HS) followed by gas chromatography/ mass spectrometry (GC/MS) for the qualitative and quantitative analysis of methyl tert-buthyl ether (MTBE) and formaldehyde (HCHO) in human blood and water samples. Cytochrome P4502A6 has important role for converting of MTBE to tert-butyl alcohol (TBA) and HCHO. To enhance the extraction capability of the HS, extraction parameters such as extraction temperature, extraction time, the ratio of headspace volume to sample volume and sodium chloride concentration have been optimized. Wide linearity range was verified in a range of 5-10000 μgL^-1 for MTBE (r²=0.9998), while those for HCHO was 5-500 μg L-1 (r²=0.9996). Detection limits for MTBE and HCHO was 1.0 μg L^-1 and 1.3 μg L^-1, respectively. Best results were obtained when the analyzed oily water samples were heated to 70 ◦C for 20 min, with the sample volume 10 mL in 20 mL vial, and NaCl 30% (w/v) was used to saturate the samples. The proposed analytical method was successfully used for the quantification of analytes in human biological samples and wastewater samples.