Sensitive determination of n-hexane and cyclohexane in human body fluids by capillary gas chromatography with cryogenic oven trapping.
A sensitive method was developed for determination of n-hexane and cyclohexane in human body fluids by headspace capillary gas chromatography (GC) with cryogenic oven trapping. Whole blood and urine samples containing n-hexane and cyclohexane were heated in a 7.5 mL vial at 70 degrees C for 15 min, and 5 mL of the headspace vapor was drawn into a glass syringe. All vapor was introduced through an injection port of a GC instrument in the splitless mode into an Rtx-Volatiles middle-bore capillary column at an oven temperature of -40 degrees C for trapping volatile compounds. The oven temperature was programmed to 180 degrees C for GC with flame ionization detection. These conditions gave sharp peaks for both n-hexane and cyclohexane, a good separation of each peak, and low background impurities for whole blood and urine. The extraction efficiencies of n-hexane and cyclohexane were 13.2-30.3% for whole blood and 12.7-20.7% for urine. The coefficients of within-day variation in terms of extraction efficiency of both compounds were 5.0-9.5% for whole blood and 3.8-10.8% for urine; those of day-to-day variation for the compounds were not greater than 16.6%. The regression equations for n-hexane and cyclohexane showed good linearity in the range of 5-500 ng/0.5 mL for whole blood and urine. The detection limits (signal-to-noise ratio = 3) for both compounds were 1.2 and 0.5 ng/0.5 mL for whole blood and urine, respectively. The data on n-hexane or cyclohexane in rat blood after inhalation of each compound are also presented.
Showa University School of Medicine, Department of Legal Medicine, Tokyo, Japan.
K
K
Kondo
X P
XP
Lee
T
T
Kumazawa
K
K
Sato
K
K
Watanabe-Suzuki
H
H
Seno
O
O
Suzuki
D000818:Animals; D002849:Chromatography, Gas; D003510:Cyclohexanes / Q000032:analysis* / Q000097:blood / Q000652:urine; D008401:Gas Chromatography-Mass Spectrometry; D006586:Hexanes / Q000032:analysis* / Q000097:blood / Q000652:urine; D006801:Humans; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results
D003510:Cyclohexanes; D006586:Hexanes; C026385:n-hexane