| |
Published:
Journal of Analytical Toxicology,
ISSN 0146-4760,
Volume 26, Number 4, May/June
pp. 189-192
Simple Method of Methylation for Gas Chromatographic Analysis
of S-Benzyl-N-acetylcysteine, a Metabolite of Toluene, in Human Urine
Setsunori Takahashi[1], Takashi Uezono[2], Atsushi
Akane[3], and Kojiro Kimura[1]
[1]Department of Legal Medicine, Shimane Medical University, Izumo 693-8501,
Japan;
[2]Department of Legal Medicine, Asahikawa Medical College, Asahikawa 078-8510,
Japan; and
[3]Department of Legal Medicine, Kansai Medical University, Moriguchi 570-8506,
Japan
A simplified method of methylation
for the determination of urinary S-benzyl-N-acetylcysteine (benzylmercapturic
acid, SBAC), a metabolite of toluene, by gas chromatography (GC) was developed.
Acidified urine samples (pH 2) were extracted once with ethyl acetate and then
derivatized to methyl ester (ME) using HCl-methanol. The optimum conditions
for derivatization for SBAC and the internal standard (S-phenethyl-N-acetylcysteine)
were reaction at 60°C for 20 min. The SBAC-ME was measured by capillary
GC. The calibration curve showed good linearity over the range of 0.2 to 5.0
mg/L (r = 0.986). This method was compared with a previously developed diazomethane
methylation method for testing urine from subjects who had sniffed toluene.
The values obtained by the two different methods were in good accordance. These
results suggest that this technique for the methylation of SBAC by means of
HCl-methanol is simpler and time-saving, thus making it feasible to determine
SBAC and other mercapturic acids in urinary samples obtained from subjects who
have been exposed to organic solvents. Reproduction
of editorial content of this journal is prohibited without publisher’s
permission.
This
article is available in its entirety by fax for $40.00 each.
Visa, MasterCard and AMEX accepted.
To
order electronically click here
or call: 847-647-2900 ext. 1323
or fax request to: 847-647-1155.
To order multiple copies click here.
Please indicate JAT
volume and issue along with page numbers. |
|
Home | Subscribe
| Current Issue | Back Issues
| Search | Advertise | Other Publications
| |
