Skip to Content
MilliporeSigma
  • Determination of levamisole and tetramisole in seized cocaine samples by enantioselective high-performance liquid chromatography and circular dichroism detection.

Determination of levamisole and tetramisole in seized cocaine samples by enantioselective high-performance liquid chromatography and circular dichroism detection.

Journal of chromatography. A (2014-08-16)
Carlo Bertucci, Daniele Tedesco, Edoardo Fabini, Anna Maria Di Pietra, Francesca Rossi, Marco Garagnani, Elia Del Borrello, Vincenza Andrisano
ABSTRACT

Levamisole, an anthelmintic drug, has been increasingly employed as an adulterant of illicit street cocaine over the last decade; recently, the use of tetramisole, the racemic mixture of levamisole and its enantiomer dexamisole, was also occasionally observed. A new enantioselective high-performance liquid chromatography (HPLC) method, performed on cellulose tris(3,5-dimethylphenylcarbamate) chiral stationary phases in normal-phase mode, was validated to determine the enantiomeric composition of tetramisole enantiomers in seized cocaine samples. Furthermore, the hyphenation of the validated HPLC method with a circular dichroism (CD) detection system allowed the direct determination of elution order and a selective monitoring of levamisole and dexamisole in the presence of possible interferences. The method was applied to the identification and quantitation of the two enantiomers of tetramisole in seized street cocaine samples.

MATERIALS
Product Number
Brand
Product Description

Caffeine, European Pharmacopoeia (EP) Reference Standard
Sigma-Aldrich
Ethyl alcohol, Pure, 190 proof, meets USP testing specifications
Sigma-Aldrich
Diethylamine, purified by redistillation, 99.5%
Sigma-Aldrich
2-Propanol, 99.5%, HPLC grade
Sigma-Aldrich
Hexane, anhydrous, 95%
Supelco
Ethanol standards 10% (v/v), 10 % (v/v) in H2O, analytical standard
Sigma-Aldrich
Cocaine free base
Sigma-Aldrich
Caffeine, meets USP testing specifications, anhydrous
Sigma-Aldrich
2-Propanol, HPLC Plus, for HPLC, GC, and residue analysis, 99.9%, poly coated bottles
Sigma-Aldrich
Ethyl alcohol, Pure, 190 proof, ACS spectrophotometric grade, 95.0%
Sigma-Aldrich
Diethylamine, ≥99.5%
Sigma-Aldrich
2-Propanol, anhydrous, 99.5%
Sigma-Aldrich
Ethanol, ≥99.5%, SAJ super special grade
Sigma-Aldrich
Hexane, HPLC Plus, for HPLC, GC, and residue analysis, ≥95%
Sigma-Aldrich
Ethanol, ≥99.5%
Sigma-Aldrich
Hexane, JIS special grade, ≥96.0%
Sigma-Aldrich
Diethylamine, SAJ special grade, ≥99.0%
Sigma-Aldrich
2-Propanol, SAJ first grade, ≥99.0%
Sigma-Aldrich
2-Propanol, JIS special grade, ≥99.5%
Sigma-Aldrich
Hexane, JIS 300, ≥96.0%, for residue analysis
Sigma-Aldrich
Diethylamine, SAJ first grade, ≥98.0%
Sigma-Aldrich
Ethanol, JIS 300, ≥99.5%, for residue analysis
Sigma-Aldrich
Ethanol, JIS 1000, ≥99.5%, for residue analysis
Sigma-Aldrich
Hexane, JIS 1000, ≥96.0%, for residue analysis
Sigma-Aldrich
Hexane, SAJ first grade, ≥95.0%
Sigma-Aldrich
Caffeine, SAJ special grade, ≥98.5%
Sigma-Aldrich
Ethanol, ≥99.5%, suitable for absorption spectrum analysis
Sigma-Aldrich
Ethanol, ≥99.5%, suitable for fluorescence
Supelco
Caffeine Melting Point Standard, Pharmaceutical Secondary Standard; Certified Reference Material
Supelco
Caffeine, Pharmaceutical Secondary Standard; Certified Reference Material