Restek at SOFT 2024
27 October-1 November
Booth 211
St. Louis, MO, U.S.
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POSTER PRESENTATIONS:
WEDNESDAY, OCTOBER 30, 12:00-2:00 P.M.
Integration of Ultrashort-Chain Compounds into the Biomonitoring of Per- and Polyfluorinated Substances in Human Plasma and Serum
Shun-Hsin Liang (presenter), Justin Steimling
Restek Corporation
Abstract
The selection of per- and polyfluoroalkyl substances (PFAS) for biomonitoring can vary depending on regional or population-specific concerns. Commonly examined PFAS encompass a spectrum from short- to long-chain compounds (C4–C10). The ultrashort-chain (USC) PFAS with carbon chain lengths of shorter than C4 have become a major concern due to their prevalence and high levels of occurrence in environmental aquatic systems. Numerous studies have observed a rapid escalation in environmental concentration of USC PFAS, raising the concern of elevated human exposure. Assessing USC PFAS levels in blood not only facilitates monitoring of human exposure but also provide a tool to investigate potential risks associated with such exposure.
A simple and reliable workflow was established in this study to provide a unique solution for the integration of ultrashort-chain compounds into the measurement of PFAS in human plasma and serum. It aimed to develop a simple and reliable workflow to simultaneously quantify C1 to C10 perfluoroalkyl carboxylic acids and perfluoroalkyl sulfonic acids, along with four alternative compounds, in human plasma and serum.
The reported method was rugged, accurate, and precise by implementing a polar-embedded
column for chromatographic analysis. Most important, this solution can offer a valuable tool for gaining insights into human exposure to these emergent ultrashort-chain PFAS.
Analysis of Δ-8-THC, Δ-9-THC, and Their Metabolites in Whole Blood by LC-MS/MS
Haley Berkland (presenter), Jamie York
Restek Corporation
Abstract
The testing of whole blood samples for tetrahydrocannabinol (Δ-9-THC) consumption is routine and has been around for many decades. Δ-9-THC is metabolized into 11-Hydroxy-Δ9-tetrahydrocannabinol (11-OH-Δ-9-THC) and further into 11-nor-9-carboxy-Δ-9-THC (Δ-9-THC-COOH). It is important to test for the parent and both metabolites to properly monitor for THC usage.
As more isomers of Δ-9-THC become available on the market, testing becomes more complicated and novel methods are needed to achieve isomeric resolution. One such isomer, Δ-8-THC, is federally unregulated in the United States and readily available for purchase in many stores. This compound forms its own hydroxylated and carboxylated metabolites, (11-OH-Δ-8-THC and Δ-8-THC-COOH), that must be chromatographically resolved from their isomeric metabolites. The resolution of isomeric metabolites is key in reporting accurate specimen findings and poor resolution, especially when one isomer is in much greater abundance than the other, can result in quantitation issues and invalid data.
In this study, an LC-MS/MS method was successfully developed for reliable and accurate testing of Δ-8/9-THC isomers and isomer metabolites in whole blood. The method was determined to be quick, rugged, and sensitive enough to meet reporting guidelines for clinical and forensic toxicology laboratories. While C18 phase columns may show some selectivity for the three isomer pairs, full resolution of the isomers is needed for accurate quantitation. To achieve this resolution on a C18 phase would likely result in a lengthy analytical runtime. The FluoroPhenyl ligand shows selectivity for all three isomer pairs, allowing for adequate separation of the analytes in a reasonable analytical runtime.
Consolidating LC-MS/MS Method Conditions for the Analysis of Alcohol Metabolites, Barbiturates, and Drugs of Abuse
Paul Connolly (presenter), Jamie York, Haley Berkland, Justin Steimling
Restek Corporation
Abstract
Efficiency is key in toxicology laboratories where multiple drug panels must be run daily. Consolidating multiple drug panels into large, multi-class drug assays can streamline the analytical testing process and reduce operating costs. To simplify the analysis of alcohol metabolites, barbiturates, THC metabolites, and drugs of abuse, three different LC-MS/MS methods were developed for each analyte class using the same analytical column and mobile phases.
A panel of 100 drugs of abuse, novel psychoactive substances, therapeutic drugs and metabolites, a panel of biomarkers of alcohol consumption, and a panel of barbiturates and cannabinoid metabolites were all analyzed using the same analytical column and mobile phase set up.
This work highlights the ability of one LC-MS/MS setup to analyze multiple toxicology panels. This allows for laboratories to simplify testing procedures, save time, and reduce operating costs.
The Analysis of Drugs of Abuse (DoA) and Novel Psychoactive Substances (NPS) in Oral Fluids by LC-MS/MS
Samantha Herbick (presenter)
Restek Corporation
Abstract
Testing for drugs in biological matrices is an important part of toxicology and workplace drug testing. The “gold standard” matrices that have been used for decades are typically blood and urine, however, the collection of these two matrices is invasive. The analysis of drugs of abuse in oral fluids is a solution that is gaining popularity due to its ease of collection compared to blood or urine collection. However, there are some issues with the buffer used in the collection devices when performing the oral fluid analysis. Finding a workflow that uses a simple sample preparation paired with accurate and robust quantitation of the analytes is important for laboratories running these tests.
A panel of 65 DoA and NPS were analyzed in oral fluid using a SALLE sample preparation technique and LC-MS/MS. This method demonstrates an accurate and robust solution for the analysis of these analytes. This method also offers a quick and efficient sample preparation procedure that cleans up with sample and removes buffer surfactants, without the need for SPE or other tedious extraction techniques, leading to faster processing of samples in high through-put laboratories.