Capillary zone electrophoresis (CZE) coupled to time-of-flight mass spectrometry (TOF-MS) applied to the analysis of illicit and controlled drugs in blood.
A new method for the determination of illicit and abused drugs in blood by capillary zone electrophoresis-electrospray ionization-time-of-flight mass spectrometry is proposed, in view of its application in clinical and forensic toxicology. The analytes (methamphetamine, methylenedioxyamphetamine, methylenedioxyethylamphetamine, methylenedioxymethamphetamine, methadone, cocaine, morphine, codeine, 6-acethylmorphine, benzoylecgonine) were separated with capillary zone electrophoresis by applying 15 kV within 25 min, in an uncoated fused-silica capillary (75 microm x 100 cm) using a 25 mM ammonium formate electrolyte solution (pH 9.5). The capillary electropherograph was coupled to time-of-flight mass spectrometry through an orthogonal electrospray ionization source, with a coaxial sheath liquid interface. The sheath liquid was composed of isopropanol-water (1:1 v/v) containing 0.5% formic acid delivered at 4 microL/min. Forensic drugs were identified by exact mass determination (mass accuracy typically < or =5 ppm) and by matching of the isotopic pattern. Under optimized conditions, linearity was assessed in the range 10-2000 ng/mL, with correlation coefficients between 0.9744 and 0.9982 for all the analytes. LODs were in the range of 2-10 ng/mL (S/N > or =3) and LOQs of 10-30 ng/mL. The CVs (tested at 40 and 800 ng/mL in biological matrix) were below 2.97% for migration times and below 14.61% for peak area ratios (analyte/internal standard). Blood samples were extracted by using a liquid-liquid extraction procedure and injected under field-amplified sample stacking conditions. The method was successfully applied to real cases.
Gottardo
Rossella
R
Department of Medicine and Public Health, Unit of Forensic Medicine, University of Verona, Verona, Italy.
Polettini
Aldo
A
Sorio
Daniela
D
Pascali
Jennifer Paola
JP
Bortolotti
Federica
F
Liotta
Eloisa
E
Tagliaro
Franco
F
D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D013287:Illicit Drugs / Q000097:blood*; D015203:Reproducibility of Results; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000295:instrumentation / Q000379:methods*; D015813:Substance Abuse Detection / Q000379:methods*
D013287:Illicit Drugs