Abstract：
The forensic analysis of amide-based synthetic cannabinoids (SCs) in seized materials is routinely performed using gas chromatography-mass spectrometry (GC-MS); however, a major challenge associated with GC-MS is the thermolytic degradation of substances with sensitive functional groups. Herein, we report the comprehensive thermal degradation and ester transformation of amide-based SCs, such as AB-FUBINACA, AB-CHMINACA, and MAB-CHMINACA, during GC-MS analysis and their treatment with analyte protectants (APs). These SCs were found to undergo thermolytic degradation during GC-MS in the presence of non-alcohol solvents. Using methanol as an injection solvent resulted in the conversion of the amide group to an ester group, producing other SCs such as AMB-FUBINACA, MA-CHMINACA, and MDMB-CHMINACA. Degradant and ester product formation has been interpreted as the adsorption of target SCs on glass wool via hydrogen bonding interactions between the active silanol and amide groups of the SCs, followed by an addition and/or elimination process. The factors found to influence the thermal degradation and/or esterification of the amide functional group include residence time, activity of glass wool, and injection volume. This report presents the fragmentation patterns of all compounds that were produced by degradation and esterification. Using 0.5 % sorbitol (AP) in MeOH as an injection solvent resulted in complete protection and improvement of the chromatographic shape of the compounds. This method has been successfully confirmed in terms of sensitivity, linearity, accuracy, and precision for standard solutions and tablet extraction using 0.5 % sorbitol in MeOH. Using AP increased the sensitivity by ten times or more compared to the use of only MeOH. The limit of detection for all analytes was determined as 25 ng/mL, and the calibration curves were linear over the concentration range of 50-2000 ng/mL. The values of accuracy error were below 11 %, and precision was less than 13 %. The effects of phytochemicals of herbal products, tablet ingredients, and biological matrices on the degradation and/or esterification and APs performance have also been evaluated in this work.
摘要：
通常使用气相色谱-质谱法（GC-MS）对缉获材料中的酰胺基合成大麻素（SC）进行法医分析；但是，与GC-MS相关的主要挑战是具有敏感官能团的物质的热解降解。在这里，我们报道了酰胺基干细胞的综合热降解和酯转化，比如AB-FUBINACA，AB-CHMINACA,和MAB-CHMINACA，在GC-MS分析和用分析物保护剂(AP)处理期间。发现这些SC在非醇溶剂存在下在GC-MS期间经历热解降解。使用甲醇作为注射溶剂导致酰胺基团转化为酯基团，产生其他SC，如AMB-FUBINACA，MA-CHMINACA,和MDMB-CHMINACA。降解和酯产物的形成已被解释为目标SCs在玻璃棉上的吸附通过活性硅烷醇和酰胺基团之间的氢键相互作用。然后是添加和/或消除过程。发现影响酰胺官能团的热降解和/或酯化的因素包括停留时间，玻璃棉的活性，和注射量。该报告介绍了通过降解和酯化产生的所有化合物的断裂模式。使用在MeOH中的0.5%山梨糖醇(AP)作为注射溶剂导致化合物的完全保护和色谱形状的改善。该方法在灵敏度方面已成功证实，线性度准确度,和使用在MeOH中的0.5%山梨糖醇的标准溶液和片剂提取的精密度。与仅使用MeOH相比,使用AP使灵敏度增加十倍或更多。所有分析物的检测限确定为25ng/mL，在50-2000ng/mL的浓度范围内，校准曲线呈线性关系。精度误差低于11%，精度低于13%。草药产品的植物化学物质的影响，片剂成分，和生物基质对降解和/或酯化和AP的性能也在这项工作中进行了评估。
