High-performance liquid chromatographic drug analysis by direct injection of whole blood samples

An ever-increasing need exists within the forensic laboratories to develop analytical processes for the qualitative and quantitative determination of a broad spectrum of new psychoactive substances. Phenylethylamine derivatives are among the major classes of psychoactive substances available on the global market and include both amphetamine analogues and synthetic cathinones. In this work, an ultra-high-performance liquid chromatography-positive ion electrospray ionization tandem mass spectrometric method (UHPLC-ESI-MS/MS) has been developed and fully validated for the determination of 19 psychoactive substances, including nine amphetamine-type stimulants and 10 synthetic cathinone derivatives, in premortem and postmortem whole blood. The assay was based on the use of 1 mL premortem or postmortem whole blood, following solid phase extraction prior to the analysis. The separation was achieved on a Poroshell 120 EC-C18 analytical column with a gradient mobile phase of 0.1% formic acid in acetonitrile and 0.1% formic acid in water in 9 min. The dynamic multiple reaction monitoring used in this work allowed for limit of detection (LOD) and lower limit of quantitation (LOQ) values of 0.5 and 2 ng mL−1, respectively, for all analytes both in premortem and postmortem whole blood samples. A quadratic calibration model was used for the 12 quantitative analytes over the concentration range of 20–2000 ng mL−1, and the method was shown to be precise and accurate both in premortem and postmortem whole blood. The method was applied to the analysis of real cases and proved to be a valuable tool in forensic and clinical toxicology.

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Determination of quinalphos in human whole blood samples by high-performance thin-layer chromatography for forensic applications

Journal of Chromatography A ◽

10.1016/j.chroma.2019.02.003 ◽

2019 ◽

Vol 1594 ◽

pp. 181-189 ◽

Cited By ~ 2

Author(s):

Praveen U Sanganalmath ◽

Purigali M Nagaraju ◽

Kuruba Sreeramulu

Keyword(s):

Thin Layer ◽

Thin Layer Chromatography ◽

Whole Blood ◽

High Performance ◽

Blood Samples ◽

Human Whole Blood ◽

Whole Blood Samples ◽

Layer Chromatography

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Identification and analysis of nine metabolites of cyclosporine in whole blood by liquid chromatography. 2: Comparison of patients' results.

Clinical Chemistry ◽

10.1093/clinchem/33.10.1851 ◽

1987 ◽

Vol 33 (10) ◽

pp. 1851-1855 ◽

Cited By ~ 10

Author(s):

G L Lensmeyer ◽

D A Wiebe ◽

I H Carlson

Keyword(s):

Whole Blood ◽

High Performance ◽

Transplant Patient ◽

Regression Line ◽

Correlation Coefficients ◽

High Performance Liquid Chromatographic ◽

Drug Concentrations ◽

Metabolite Concentrations ◽

Liquid Chromatographic ◽

Transplanted Organs

Abstract We used a "high-performance" liquid-chromatographic assay [for parent cyclosporine (CsA) and nine metabolites] and a radioimmunoassay to detail the diversity of results among whole-blood samples from patients with transplanted organs. Heterogeneous populations of metabolites in samples collected just before the next dose of CsA were detected by HPLC, with CsA, M17, M1, or M8 predominating; M21, M203-218, MUNDF1, and M18 were detected in lesser amounts. Results by HPLC vs RIA for CsA or for individual metabolites vs CsA (or RIA) were diverse, with correlation coefficients (r) ranging from 0.058 to 0.933. RIA vs HPLC(sum of CsA + metabolites) gave the best comparison (slope = 0.931, y-intercept 14 micrograms/L, r = 0.933); but the scatter of data about the regression line remained significant (Sy/x = 132 micrograms/L). Most important, RIA/HPLC(CsA) vs HPLC(sum of metabolites) was remarkably poor (r = 0.222). A 12-h pharmacokinetic curve (for drug concentrations in a heart-transplant patient) displayed dissimilar times for peak concentrations of CsA and metabolites; each differed in the proportion (48% to 81% of peak concentration) eliminated from blood over the 12 h. These studies exemplify the utility of a more-inclusive, specific assay to monitor the diverse disposition of cyclosporines in patients and to demonstrate the errors associated with use of the RIA/HPLC ratio technique to predict metabolite concentrations.

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