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In the last decade there has been a dramatic increase in the availability and abuse of synthetic cathinones - new amphetamine-like stimulants. Even though their abuse during pregnancy could have serious adverse effects on the fetus, cathinones are not readily included in neonatal toxicological screenings. Meconium (first neonatal stool) is the specimen of choice to reveal long term drug exposure, however as it is a highly complex matrix, the sample preparation is a critical step before the instrumental analysis. The aim of this work was to develop a suitable meconium sample extraction technique using the advantages of salting-out assisted liquid-liquid extraction (SALLE) and using only MS-friendly organic ammonium salts. We further developed and validated liquid chromatography tandem-mass spectrometry method for the determination of 'traditional' stimulants (methamphetamine, amphetamine, MDMA) and cathinones (mephedrone, methylenedioxypyrovalerone (MDPV), α-pyrrolidinopentiophenone (α-PVP), methylone, butylone, flephedrone, and naphyrone). Matrix-matched calibration was prepared in the concentration range 10-2000 ng/g. The limits of quantification were determined as 10 ng/g, recoveries ranged from 48.2% to 94.3% and the matrix effect was between 60.2% and 101.4%. Accuracy (86.1-114.5%) and precision (4.9-14.9%) were determined and all validation criteria were met for all analytes except for naphyrone. Finally, our analytical method was tested on a set of real meconium samples, which were found positive for amphetamine, methamphetamine and methylone, thus demonstrating the validity of the method.
- MeSH
- amfetaminy analýza MeSH
- amoniové sloučeniny chemie MeSH
- extrakce kapalina-kapalina metody MeSH
- komplikace těhotenství diagnóza MeSH
- lidé MeSH
- limita detekce MeSH
- mekonium chemie MeSH
- novorozenec MeSH
- odhalování abúzu drog metody MeSH
- poruchy spojené s užíváním psychoaktivních látek diagnóza MeSH
- stimulanty centrálního nervového systému analýza MeSH
- studie proveditelnosti MeSH
- tandemová hmotnostní spektrometrie metody MeSH
- těhotenství MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Check Tag
- lidé MeSH
- novorozenec MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- amfetaminy * analýza moč MeSH
- chemické techniky analytické metody MeSH
- chromatografie kapalinová * MeSH
- lidé MeSH
- nové syntetické drogy MeSH
- plynová chromatografie s hmotnostně spektrometrickou detekcí * MeSH
- poruchy spojené s užíváním psychoaktivních látek diagnóza MeSH
- reprodukovatelnost výsledků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- MeSH
- chromatografie iontoměničová MeSH
- fenylalanin chemie MeSH
- glutamin chemie MeSH
- hormon uvolňující thyreotropin chemická syntéza izolace a purifikace MeSH
- izotopové značení MeSH
- lidé MeSH
- peptidové fragmenty chemická syntéza izolace a purifikace MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- MeSH
- financování organizované MeSH
- Publikační typ
- abstrakty MeSH
We report on the hyphenation of the modern flow techniques Lab-In-Syringe and Lab-On-Valve for automated sample preparation coupled online with high-performance liquid chromatography. Adopting the bead injection concept on the Lab-On-Valve platform, the on-demand, renewable, solid-phase extraction of five nonsteroidal anti-inflammatory drugs, namely ketoprofen, naproxen, flurbiprofen, diclofenac, and ibuprofen, was carried out as a proof-of-concept. In-syringe mixing of the sample with buffer and standards allowed straightforward pre-load sample modification for the preconcentration of large sample volumes. Packing of ca. 4.4 mg microSPE columns from Oasis HLB® sorbent slurry was performed for each sample analysis using a simple microcolumn adapted to the Lab-On-Valve manifold to achieve low backpressure during loading. Eluted analytes were injected into online coupled HPLC with subsequent separation on a Symmetry C18 column in isocratic mode. The optimized method was highly reproducible, with RSD values of 3.2% to 7.6% on 20 µg L-1 level. Linearity was confirmed up to 200 µg L-1 and LOD values were between 0.06 and 1.98 µg L-1. Recovery factors between 91 and 109% were obtained in the analysis of spiked surface water samples.
