Browsing by Subject "Reference standard"

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  • Mesihää, Samuel; Rasanen, Ilpo; Ojanperä, Ilkka (2020)
    Purity assessment of seized material containing new psychoactive substances (NPS) is complicated without appropriate primary reference standards. Here we present a method for fast quantitative estimation of stimulant-type NPS with use of secondary reference standards, based on gas chromatography nitrogen chemiluminescence detection coupled with atmospheric pressure chemical ionization quadrupole time-of-flight mass spectrometry (GC-NCD-APCI-QTOFMS). Quantification was based on the detector’s N-equimolar response to nitrogen and using two external nitrogen-containing calibrators, MDMA for prim- and sec- amines and α-PVP for tert- amines. Sample preparation involved dissolving the seized powdery material in an organic solvent mixture followed by acylation with N-methyl-bis-trifluoroacetamide (MBTFA). The method’s between-day accuracy and precision over a five-day period was measured for twenty-eight stimulants: the grand mean equimolarity was 91.9% (CV 5.5%), as compared with primary reference standards. The GC-NCD-APCI-QTOFMS method was applied to the purity estimation of forty-two seized powder samples previously found to contain stimulant-type NPS by appropriate methods. The quantitative results were compared to those obtained by an established method relying on liquid chromatography chemiluminescence detection (LC-CLND), the latter using caffeine as an external calibrator. The mean difference of purity values between the methods was 8.1% (range 0.4 - 26.7%). The presented method might find use as a tool for instant purity assessment in forensic laboratories.
  • Rasanen, Ilpo; Kyber, Marianne; Szilvay, Ilmari; Rintatalo, Janne; Ojanperä, Ilkka (2019)
    Drug seizures involving a wide variety of emerging new psychoactive substances (NPS) call for new approaches for instant quantification and valuation. Liquid chromatography-chemiluminescence nitrogen detection (LC-CLND) was used in the quantification of opioids with a single secondary standard (caffeine), utilizing the detector's equimolar response to nitrogen. The mean N-equimolarity of CLND for ten fentanyl derivatives and U-47700 by the present LC-CLND method was 96.4% (range 91-101%). The furanylfentanyl samples consisted of 112 powdery samples with a mean (median, range) hydrochloride purity of 13% (4.9%, 0.08-100%). The purity distribution of the furanylfentanyl samples was distinctly bipartite, showing only lower than 9% (NI = 98) and higher than 60% (N=14) purities. The carfentanil samples consisted of eight brownish sticky samples with a mean (median, range) hydrochloride purity of 0.064% (0.063%, 0.052-0.092%). The U-47700 samples consisted of seven powdery samples with a mean (median, range) hydrochloride purity of 89.0% (100%, 51-100%). The present application to synthetic opioid analysis widens the scope of the established LC-CLND method, previously found useful for single-calibrant quantification of stimulant/hallucinogenic and cannabinoid type of NPS. (C) 2019 Elsevier B.V. All rights reserved.