Vogliardi Susanna, Favretto Donata, Frison Giampietro, Ferrara Santo Davide, Seraglia Roberta, Traldi Pietro
Forensic Toxicology and Antidoping Unit, University Hospital of Padova, Padova, Italy.
J Mass Spectrom. 2009 Jan;44(1):18-24. doi: 10.1002/jms.1463.
Matrix-assisted laser desorption/ionisation (MALDI) mass spectrometry was used for the rapid detection of cocaine, benzoylecgonine and cocaethylene in hair. Different MALDI sample preparation procedures have been tested and the employment of a multi-layer 'graphite-sample-electrosprayed alpha-cyano-4-hydroxycinnamic acid (HCCA)' yielded the best results for standard solutions of the target analytes. The same approach was subsequently applied to hair samples that were known to contain cocaine, benzoylecgonine and cocaethylene, as determined by a classical GC-MS method. It was however necessary to extract hair samples by incubating them in methanol/trifluoroacetic acid for a short time (15 min) at 45 degrees C; 1 microl of the obtained supernatant was deposed on a metal surface treated with graphite, and HCCA was electrosprayed on it. This procedure successfully suppressed matrix peaks and was effective in detecting all the target analytes as their protonated species. The results obtained give further confirmation of the effectiveness of the MALDI for detecting drugs and their metabolites in complex biological matrices. The method can be useful as a fast screening procedure to detect the presence of cocaine and metabolites in hair samples.
基质辅助激光解吸/电离（MALDI）质谱法用于快速检测毛发中的可卡因、苯甲酰爱康宁和可口卡因。已测试了不同的MALDI样品制备程序，对于目标分析物的标准溶液，采用多层“石墨-样品-电喷雾α-氰基-4-羟基肉桂酸（HCCA）”产生了最佳结果。随后，将相同的方法应用于已知含有可卡因、苯甲酰爱康宁和可口卡因的毛发样品，这些样品是通过经典的气相色谱-质谱法测定的。然而，有必要将毛发样品在甲醇/三氟乙酸中于45℃孵育短时间（15分钟）进行提取；将1微升获得的上清液滴在经石墨处理的金属表面上，并在其上进行HCCA电喷雾。该程序成功抑制了基质峰，并能有效地检测到所有目标分析物的质子化形式。所获得的结果进一步证实了MALDI在复杂生物基质中检测药物及其代谢物的有效性。该方法可用作快速筛查程序，以检测毛发样品中可卡因及其代谢物的存在。
