Cocaine, benzoylecgonine and cocaethylene in hair of chewed coca leave by UPLC-DAD

LEDA GIANNUZZI, LUIS A. FERRARI, DANIELA SEDAN, FERNANDO GALASSI, MARIANO MONJES, BRENDA CRUZ, JOSEPH BLOOM.

Geneva, Suiza

Congreso; The International Association of Forensic Toxicologists. TIAFT. 47 th International Meeting.; 2009

The International Association of Forensic Toxicologists. TIAFT

Introduction: The chewing (¡°coqueo¡±) of cocaine leaves (Erytroxillum coca) is habitual in the NW and Argentine NE, having very peculiar sociocultural and religious connotations. Although the cases of abuse of the ¡°coqueo¡± are not habitual in these communities, characteristic signs and symptoms have been reported. After an exhaustive bibliographical research, the authors have found few studies or data collections with respect to the presence in leaf of diverse cocaine related compound in pericraneal hair. Given the low levels of concentration that are possible to hope, a new method of liquid chromatography practiced, UPLC (Ultra performance liquid chromatography), of extraordinary rapidity and resolution, due to the filling of column with particles <2m. The system was connected to a DAD detector. However, previously, hair samples were analyzed by radioimmunoassay (RIA) for the cocaine metabolite benzoylecgonine (BZE) in an attempt to verify a history of coca leave use. Aim: The propose of our work was to study Cocaine (C), benzoylecgonine (BZ) and cocaethylene (CE) in pericraneal hair of individual that chewing of cocaine leaves within or without simultaneous alcoholic beverages.   Material and Methods: Samples of pericraneal hair of 10 consumers of cocaine leaf were analyzed by RIA and after by UPLC-DAD. Initially, we washed the hair with dichloromethane and water to 37¨¬C. The washing liquids were kept for later analysis. Next, the samples were processed with HCl 0.1 N to 50¨¬C during 24 hours, and then filtrate. The water extract was processed by means of SPE (Bond Elut C-18), retaken with 500 ¥ìL of methanol. The extracts were injected in an equipment Aquity UPLC (Waters), with column C18 (50 x 2.1 mm id) with particle size of 1.8 ¥ìm. Mobile phase: potassium phosphate buffer, 20 mM, pH 7. DAD Detector 9695 Waters. LOD and LOQ of 0.1ng/mg and 0, 5 ng/mg. Results: In three cases were detected BZ by UPLC-DAD (Rt: 3.12 m) and in two cases  CE was detected (Rt: 3.92 m). BZ concentration was in the range: 3.7-30 ng/mg of hair and for CE: 0.4-1.2 ng/mg. However, in few cases were observed C signal and we couldn¡¯t quantify by UPLC-DAD (< LOQ). We will discuss possible incidence of the entrance route, type and/or variety of coca leaf consumed, in the cocaine detection in hair and origin of CE in chewing coca leave persons (¡°coqueros¡±) Conclusion: 1. [BZ] > [C]. 2. In case of simultaneous consumption of alcohol and coca leaves, it¡¯s possible to detect CE. 3. Its necessary to analyze other compound that be pattern of coca leave consume.