Determination of p‐Methoxyamphetamine by Capillary Electrophoresis with Diode Array Detection from Urine and Plasma Samples

Abstract

In recent years, a number of newer designer drugs have entered the illicit drug market. The amphetamine derivatives represent the largest group of designer drugs. This paper describes a method for quantifying p-methoxyamphetamine in human plasma and urine by capillary electrophoresis with a diode array detector. Using an aqueous pH 2.5 phosphate buffer, CE analysis gave peaks with good symmetry and reproducible migration time. Under these experimental conditions, the p-methoxyamphetamine was resolved in 7 min and without interferences from biological matrices. The identification using the migration time was confirmed by UV spectra recorded with a diode array detector DAD (190-350 nm). Prior to CE-DAD analysis, a simple solid phase extraction (SPE) was used for sample cleanup. The main advantages of the present method lie in its simplicity and clean and reliable extraction from plasma and urine. The method was validated according to international guidelines.

LC–MS analysis of trimethoxyamphetamine designer drugs (TMA series) from urine samples

“…The lower limits of detection (LLODs) and quantification (LLOQs) were from 4.26 to 9.12 ng/mL and from 13.18 to 29.22 ng/mL, respectively (Table 2). This level of sensitivity was comparable to that reported for similar analytes by capillary electrophoresis-mass spectrometry (CE-MS) [14][15][16] and was suitable for confirmation of the presence of the analytes in urine samples.…”

“…In view of the simplicity, sensitivity and selectivity, the method is recommendable for the determination of these amphetamine derivatives in clinical pharmacology, bioavailability studies and forensic toxicology. LC-MS analysis of trimethoxyamphetamines does not require derivatization and is comparable in sensitivity, accuracy and precision to GC-MS and CE-MS for analogous compounds [7,[14][15][16]23].…”

“…Solid-phase extraction is the most widely used preconcentration procedure. As reported in our previous papers, SPE on C 18 cartridge was successfully used for extraction/purification of methoxy and dimethoxyamphetamines from biological matrices [14][15][16]. The same extraction conditions can be extended to determine the molecular congeners as the trimethoxyamphetamines.…”

“…Amphetamines were extracted using our previously described procedure for other amphetamine analogous [14][15][16]. Briefly, urine samples (1 mL) were spiked with 50 ng of IS (TMA-3) and mixed with hydrogen carbonate buffer (100 mM, pH 10, 1 mL).…”

Simultaneous determination of new thioamphetamine designer drugs in plasma by capillary electrophoresis coupled with mass spectrometry

“…The residue was reconstituted in 1 mL of the mobile phase. This method was also successfully applied to plasma extraction 20…”