Capillary zone electrophoresis (CZE) coupled to time‐of‐flight mass spectrometry (TOF‐MS) applied to the analysis of illicit and controlled drugs in blood

Abstract

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.

Analysis of the alcohol biomarker phosphatidylethanol by NACE with on‐line ESI‐MS

“…As suggested by several authors the polyimide protective coating of the capillary was burned off from the outlet side for 3 cm length and the edge of the capillary was cut straight to prevent abnormal nebulization [27].…”

Investigation of in‐line solid‐phase extraction capillary electrophoresis for the analysis of drugs of abuse and their metabolites in water samples

“…However, the application of CE for drugs of abuse has been mainly focused to the optimization of the separation step [9,10,13] and to the analysis of biological samples. As an example, Gottardo et al [11] described a new method for the determination of illicit drugs by capillary electrophoresis -electrospray ionization-time of flight-mass spectrometry in blood samples reaching limits of quantification ranging from 10 to Igor Botello Francesc Borrull Carme Aguilar Marta Calull 30 ng/mL. Also, da Costa et al [14] and Alnajjar et al [15] developed methodologies for the determination of illicit drugs and its metabolites in urine samples.…”

In-line solid-phase extraction–capillary electrophoresis coupled with mass spectrometry for determination of drugs of abuse in human urine

“…Capillary electrophoresis (CE) has been proved to have great potential in the determination of drugs of abuse because of its excellent separation efficiency, low sample and solvent volumes, and high versatility in terms of separation modes [5][6][7]. These characteristics of CE make it suitable for the needs of forensic science laboratories [6,8,9].…”