Simultaneous determination of urinary hippuric acid, o-, m- and p-methylhippuric acids, mandelic acid and phenylglyoxylic acid for biomonitoring of volatile organic compounds by gas chromatography–mass spectrometry

摘要: Abstract A sensitive and precise method for the simultaneous determination of hippuric acid, o -, m - p -methylhippuric acids, mandelic acid phenylglyoxylic which are major urinary metabolites toluene, -xylenes, styrene ethylbenzene, respectively, was developed. These were converted into their methyl ester derivatives with methanol in hydrochloric then quantitated by gas chromatography–mass spectrometry (GC–MS) selected ion monitoring using a DB-1 capillary column. The injected compounds quantitatively reproducibly resolved within 19 min detection limit 8–27 pg. calibration curves linear range 0.05–25 μg each compound, correlation coefficients above 0.9999. This successfully used to analyze small amounts both rat human urine samples without any interference from coexisting substances. Overall recoveries these spiked 92–104%. analytical results contents presented.