ElSohly M A, Feng S
ElSohly Laboratories, Incorporated (ELI), Oxford, Mississippi 38655, USA.
J Anal Toxicol. 1998 Jul-Aug;22(4):329-35. doi: 10.1093/jat/22.4.329.
Gas chromatography-mass spectrometry (GC-MS) analysis of meconium specimens screening positive for cannabinoids by the EMIT 20 Assay showed a low confirmation rate for 11-nor-9-carboxy-delta 9-tetrahydrocannabinol (THCCOOH). A study was designed to investigate the possible contribution of other delta 9-tetrahydrocannabinol (THC) metabolites, including glucuronides, to the overall response of the EIA. delta 9-THC-glucuronide was synthesized in order to develop the most efficient procedure for hydrolysis of glucuronides in meconium. Procedures were developed for the extraction and GC-MS analysis of delta 9-THC, 11-OH-delta 9-THC, 8 alpha- and 8 beta-OH-delta 9-THC, 8 beta,11-diOH-delta 9-THC, and THCCOOH, after enzymatic hydrolysis of meconium extracts. It is concluded that enzymatic hydrolysis of meconium extracts is necessary for efficient recovery of delta 9-THC metabolites; delta 9-THC and its 8-OH metabolite(s) are basically absent in meconium specimens; and 11-OH-delta 9-THC and 8 beta,11-diOH-delta 9-THC contribute significantly to the immunoassay response of meconium extracts. Analysis of several meconium specimens that screened positive for cannabinoids but failed to confirm for THCCOOH showed significant amounts of 11-OH-delta 9-THC and 8 beta,11-diOH-delta 9-THC. Therefore, GC-MS confirmation of cannabinoids in meconium should include analysis for these two metabolites in addition to THCCOOH.
采用发射免疫分析法（EMIT 20法）检测胎粪标本中大麻素呈阳性的气相色谱-质谱联用（GC-MS）分析显示，11-去甲-9-羧基-δ9-四氢大麻酚（THCCOOH）的确认率较低。设计了一项研究，以调查包括葡糖苷酸在内的其他δ9-四氢大麻酚（THC）代谢物对酶免疫分析（EIA）总体反应的可能贡献。合成了δ9-THC-葡糖苷酸，以便开发出最有效的胎粪中葡糖苷酸水解方法。开发了胎粪提取物酶水解后，对δ9-THC、11-羟基-δ9-THC、8α-和8β-羟基-δ9-THC、8β,11-二羟基-δ9-THC以及THCCOOH进行提取和GC-MS分析的方法。得出的结论是，胎粪提取物的酶水解对于有效回收δ9-THC代谢物是必要的；胎粪标本中基本不存在δ9-THC及其8-羟基代谢物；11-羟基-δ9-THC和8β,11-二羟基-δ9-THC对胎粪提取物的免疫分析反应有显著贡献。对几份大麻素筛查呈阳性但THCCOOH未能确认的胎粪标本进行分析，结果显示存在大量的11-羟基-δ9-THC和8β,11-二羟基-δ9-THC。因此，胎粪中大麻素的GC-MS确认除了THCCOOH外，还应包括对这两种代谢物的分析。
