Naslov
Micro-HPLC-UV analysis of cocaine and its adulterants seized by Austrian police in period from 2012 to 2017

Autori
Vinković, Kristinka ; Galić, Nives ; Schmidt, G. Martin

Kolaboracija
CEEPUS , project CIII-RO0010-10-1516 and CIII-RO-0010-10-1617

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, prošireni sažetak, znanstveni

Izvornik
18th International Chromatography school / Ašperger, Danijela ; Ukić, Šime - Zagreb : Fakultet kemijskog inženjerstva i tehnologije Sveučilišta u Zagrebu, 2018, 35-36

ISBN
978-953-6470-85-3

Skup
18th International Chromatography School

Mjesto i datum
Zagreb, Hrvatska, 14.06.2018. - 15.06.2018

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Cocaine ; levamisole HCl ; phenacetin ; caffeine ; lidocaine HCl ; micro-HPLC

Sažetak
The worldwide consumption of illicit drugs presents a big problem in terms of health care and prosecution. In the recent years, hundreds of novel psychoactive substances came up and were traded via the Internet, but there is still a big demand for classic illicit drugs such as cocaine, heroin, cannabis and ecstasy. Among these, cocaine particularly is frequently altered not only with excipients, but also with other physiologically active substances. The goal of this work was to develop and validate a simple micro-HPLC method with UV detection of cocaine and its adulterants at four different wavelengths. The advantages of this approach were decreased costs of analyses in comparison with usual LC-MS/MS analyses and minimized production of organic waste due to micro flow rate of mobile phase which was 70 μL/min. Six cocaine adulterants were chosen according to the estimation of their appearance frequency in cocaine samples seized by the Austrian police: caffeine, procaine, levamisole, phenacetin, lidocaine and benzocaine. The analytes were separated on the C18 column. The detection wavelengths of the analytes were set to maxima of the UV absorbance spectra to improve the sensitivity and selectivity. Adequate pH value of the mobile phase was estimated to range from 4.5 to 6.0 according to pKa values of analytes with respect to the optimal pH range for C18 column operation and pH of 5.5 was proven to give best results in terms of selectivity and peak shapes. Application of gradient elution improved peak shapes of strongly retained compounds and time of analysis was set to 18 minutes. Sample concentration was adjusted to 0.5 mg/mL and injection volume was 0.1 μL to ensure sample solubility in given diluent, achieve optimal sensitivity, and to prevent column overload and analyte carry over. After development and validation, the method was applied for the analysis of 110 cocaine samples seized from dealers in Austria to reveal the trend in terms of composition of the samples from 2013-2017. Cocaine was found as its hydrochloride salt in all cases and the purity grades varied considerably. Purity of the cocaine HCl increased during the last years. The most frequent adulterants were levamisole HCl and phenacetin, followed by caffeine and lidocaine HCl. There was a trend of higher purity of cocaine samples while number of adulterants became less in term of mass fraction and frequency of appearance. The variety of composition might be additionally dangerous for consumers, who cannot estimate the proper amount for consummation.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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