Quantifying quantify 64 drugs, illicit substances, and D- and L- isomers in human oral fluid with liquid-liquid extraction

Abstract

Although human oral fluid has become more routine for quantitative drug detection in pain management, detecting a large scope of medications and substances is costly and technically challenging for laboratories. This paper presents a quantitative assay for 64 pain medications, illicit substances, and drug metabolites in human oral fluid. The novelty of this assay is that it was developed on an older model AB SCIEX 4000 instrument and renders obscure the need for more technical and expensive laboratory equipment. This method includes addition of internal standard and a 2-step liquid-liquid extraction and dry-down step to concentrate and clean the samples. The samples were suspended in 50% MeOH in water and separation and detection was accomplished using triple quadrupole mass spectrometry (LC-MS/MS). Separation was achieved using reverse-phase liquid chromatography with detection by LC-MS/MS. A second injection was done in negative mode to determine THC-COOH concentration as an indicator of THC. An aliquot of the (already) extracted samples was analyzed for D- and L- isomers of amphetamine and methamphetamine using a chiral column. The standard curve spanned from 5 to 2000 ng/mL for most of the analytes (1 to 2000 ng/mL for fentanyl and THC-COOH) and up to 1000 ng/mL for 13 analytes. Pregabalin and gabapentin ranged from 25 to 2000 ng/mL. The result is a low-cost method for the sensitive detection of a wide-ranging oral fluid menu for pain management. This assay has a high sensitivity, and good precision and accuracy for all analytes with an older model mass spectrometer.

A Human Oral Fluid Assay for D- and L- Isomer Detection of Amphetamine and Methamphetamine Using Liquid-Liquid Extraction

“…In this paper, we ofer a novel approach for a fast, accurate, and applicable method to quantify the D-and Lisomers of (meth)amphetamine in human oral fuid specimens using liquid-liquid extraction and LC-MS/MS with an older model AB SCIEX 4000 instrument as an extension of larger ODT assay. A preprint version of this assay paper has been published [13]. Each patient sample was initially analyzed for 63 targeted analytes using LC-MS/MS with the same extracts injected a second time using a delta-9 tetrahydrocannabinol (THC)-specifc (ES) negative assay to capture the THC.…”

Analysis of D- and L- Isomers of (Meth)amphetamine in Human K2EDTA Plasma

“…Although liquid chromatography tandem mass spectrometry (LC-MS/MS) assays that detect (meth)amphetamine from human urine or oral fluid matrices are commonplace, specificity of D-and L-isomers can be methodologically challenging [8][9][10]. And although human blood plasms LC-MS/MS assays that identify (meth)amphetamine have been deployed [11], less available are plasma assays for accurate enantiomeric delineation for independent clinical laboratories.…”

“…Accordingly, this study describes a validated laboratory developed LC-MS/MS assay to quantify the enantiomeric forms of (meth)amphetamine) in human blood plasma samples. The assay was developed in parallel with an assay for 63 electro spray (ES) positive analytes that reflected identify D-and L-forms of (meth)amphetamine [12]. The result is a human blood plasma assay that provides an accurate quantitative view of on-board D-and Lenantiomeric (meth)amphetamine in the blood stream for the independent clinical laboratory.…”

Analysis of D- and L- Isomers of (Meth)amphetamine in Human K2EDTA Plasma

“…Accordingly, this study describes a validated laboratory develop LC-MS/MS assay to quantify the enantiomeric forms of (meth)amphetamine) in human blood plasma samples. The assay was developed in parallel with an assay for 63 electro spray (ES) positive analytes that reflected identify D--and L-forms of (meth)amphetamine [11]. The result is a human blood plasma assay amphetamine were added in an amount to make a 4000 ng/mL stock of each isomer so that combined they would produce an 8000 ng/mL solution of total amphetamine and methamphetamine.…”