Irving J, Leeb B, Foltz R L, Cook C E, Bursey J T, Willette R E
J Anal Toxicol. 1984 Jul-Aug;8(4):192-6. doi: 10.1093/jat/8.4.192.
A comparison was made of several cannabinoid urine assays. Two hundred randomly selected urine specimens were initially screened by two enzyme immunoassays (EMIT-st and EMIT-d.a.u.) and a radioimmunoassay (Abuscreen RIA). Selected specimens found positive by any of these methods were further analyzed by gas-liquid chromatography with flame ionization detection (GLC/FID), gas chromatography/mass spectrometry (GC/MS), and an experimental RIA from Research Triangle Institute (RTI RIA). The GLC/FID method gave confirmations in 69 to 92% of the samples, depending on the method used and the cut-off employed. GC/MS confirmed 98% of the EMIT and RIA positives using a low cut-off (20 ng/mL). All RIA positives at 100 ng/mL were confirmed by GC/MS. There was complete agreement between the RTI RIA and the EMIT assays, but not with the Abuscreen RIA at the 100 ng/mL cut-off. The study illustrates that care must be exercised in establishing assay cut-offs and the designation of false positive results.
对几种大麻素尿液检测方法进行了比较。最初，用两种酶免疫分析法（EMIT-st和EMIT-d.a.u.）和一种放射免疫分析法（Abuscreen RIA）对200份随机选取的尿液标本进行筛查。通过这些方法中任何一种检测出呈阳性的选定标本，再用带有火焰离子化检测的气液色谱法（GLC/FID）、气相色谱/质谱法（GC/MS）以及来自三角研究园研究所的一种实验性放射免疫分析法（RTI RIA）进行进一步分析。根据所使用的方法和采用的临界值，GLC/FID方法在69%至92%的样本中给出了确认结果。使用低临界值（20纳克/毫升）时，GC/MS确认了98%的EMIT和RIA阳性样本。所有100纳克/毫升的RIA阳性样本均被GC/MS确认。RTI RIA与EMIT检测方法完全一致，但在100纳克/毫升临界值时与Abuscreen RIA不一致。该研究表明，在确定检测临界值和假阳性结果的判定时必须谨慎。
