TY - JOUR
T1 - Conversion of γ-hydroxybutyric acid to a fluorescent derivative
T2 - A method for screening
AU - Matsuda, Kumi
AU - Asakawa, Naoyuki
AU - Iwanaga, Megumi
AU - Gohda, Akinaga
AU - Fukushima, Sunao
AU - Ishii, Yuji
AU - Yamada, Hideyuki
N1 - Funding Information:
Acknowledgments This work was supported by Health and Labour Sciences Research Grants from the Ministry of Health, Labour and Welfare, Japan.
PY - 2006/7
Y1 - 2006/7
N2 - Conversion of γ-hydroxybutyric acid (GHB) to a fluorescent derivative using 3-bromomethyl-6,7-dimethoxy-1-methyl-1,2-dihydroquinoxaline-2-one (Br-DMEQ), and its application to drug screening were studied. Br-DMEQ reacted with the carboxyl group of sodium GHB in the presence of a potassium salt and crown ether to produce a fluorescent derivative, which could be easily detected by thin-layer chromatography (TLC). An electrospray ionization mass spectrum of the fluorogenic product supported the expected structure. The Br-DMEQ-derivatized GHB gave an Rf value of 0.49 on TLC, which was easily distinguished from 19 other carboxylic acids; all of the latter had Rf values over 0.61. Various sodium carboxylates including sodium GHB reacted with Br-DMEQ in the presence of KCl, but the free forms of the carboxylic acids did not react under these conditions. When aqueous solution containing GHB was pretreated with sulfuric acid, GHB was converted to γ-butyrolactone, resulting in removal of its reactivity with Br-DMEQ. By such analysis following the derivatization, with and without the above pre-treatment with sulfuric acid, GHB added to human urine could be specifically detected, although the limit of detection was about 100μg/ml, which was 20 times higher than the endogenous blood GHB level. Therefore, the present method seems useful for screening GHB present in a solid state such as powder and tablets, and also in urine samples obtained in overdose cases.
AB - Conversion of γ-hydroxybutyric acid (GHB) to a fluorescent derivative using 3-bromomethyl-6,7-dimethoxy-1-methyl-1,2-dihydroquinoxaline-2-one (Br-DMEQ), and its application to drug screening were studied. Br-DMEQ reacted with the carboxyl group of sodium GHB in the presence of a potassium salt and crown ether to produce a fluorescent derivative, which could be easily detected by thin-layer chromatography (TLC). An electrospray ionization mass spectrum of the fluorogenic product supported the expected structure. The Br-DMEQ-derivatized GHB gave an Rf value of 0.49 on TLC, which was easily distinguished from 19 other carboxylic acids; all of the latter had Rf values over 0.61. Various sodium carboxylates including sodium GHB reacted with Br-DMEQ in the presence of KCl, but the free forms of the carboxylic acids did not react under these conditions. When aqueous solution containing GHB was pretreated with sulfuric acid, GHB was converted to γ-butyrolactone, resulting in removal of its reactivity with Br-DMEQ. By such analysis following the derivatization, with and without the above pre-treatment with sulfuric acid, GHB added to human urine could be specifically detected, although the limit of detection was about 100μg/ml, which was 20 times higher than the endogenous blood GHB level. Therefore, the present method seems useful for screening GHB present in a solid state such as powder and tablets, and also in urine samples obtained in overdose cases.
UR - http://www.scopus.com/inward/record.url?scp=33747498443&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33747498443&partnerID=8YFLogxK
U2 - 10.1007/s11419-006-0007-1
DO - 10.1007/s11419-006-0007-1
M3 - Article
AN - SCOPUS:33747498443
SN - 1860-8965
VL - 24
SP - 41
EP - 47
JO - Forensic Toxicology
JF - Forensic Toxicology
IS - 1
ER -