Lab Matters Summer 2021 | Page 56

APHL 2021 Poster Abstracts
Environmental Health frequencies and concentrations . The diversity of the cyanobacteria populations and variety of cyanotoxins detected indicate that freshwater cyanobloom dynamics in Pennsylvania exhibit an increased complexity that must be considered while determining state recreational advisory limits to protect the public and the environment .
Presenter : Pamela Higgins , Pennsylvania Department of Environmental Protection , Bureau of Laboratories , pahiggins @ pa . gov
A Total Analytical Workflow Solution for Anionic Polar Pesticides in Foods with High Water Content
E . Britton , Waters Corporation , Milford , MA
Public concern over anionic pesticides in the food supply continues to grow due to possible negative health impacts , leading to increased surveillance by regulators . To date , many anionic polar pesticide analyses require derivatization to achieve chromatographic retention and highest-performing instruments to enable trace detection limits . Increased demand for testing makes fast , simplified and effective workflows that meet regulatory guidelines ideal . Recently , UPLC with tandem quadrupole mass spectrometry utilizing HILIC was shown to be an effective method of analysis that does not require derivatization . The study presented here will highlight updates to this method which includes the successful analysis of eight pesticides ( AMPA , glyphosate , n-acetyl glufosinate , glufosinate , n-acetyl AMPA , ethephon , fosetyl aluminum and phosphonic acid ) in tomato and cucumber using a compact , accessible mass spectrometer .
Presenter : Jenifer Lewis , Waters Corporation , jenifer _ lewis @ waters . com
Detection of THC and its Metabolites in Plasma Using µ Elution SPE Cleanup and UPLC-MS / MS
E . Britton , Waters Corporation , Milford , MA
Determination of illegal cannabis use is one of the most requested assays from clients and law enforcement agencies to forensic and toxicology laboratories . The analysis of Δ9-tetrahydrocannabinol ( THC ) and its metabolites can be challenging , as they are prone to non-specific binding during sample preparation and manipulation . It is advantageous for laboratories to employ a simple sample preparation workflow with the least number of steps to decrease the likelihood of analyte loss while also effectively removing matrix interferences like phospholipids . Here , we present a total analytical workflow solution for the extraction and analysis of THC , 11-Nor-9- carboxy-Δ9-tetrahydrocannabinol ( THC-COOH ) and 11-Hydroxy-Δ9- tetrahydrocannabinol ( THC-OH ) from plasma using an Oasis PRiME HLB µ Elution Plate followed by UPLC-MS / MS analysis .
Presenter : Jenifer Lewis , Waters Corporation , jenifer _ lewis @ waters . com
Simplifying the Extraction of Opiates from Hydrolyzed and Non-Hydrolyzed Urine Using Automated Supported Liquid Extraction Prior to GC / MS Analysis
S . Marin , L . Williams and E . Gairloch , Biotage , Charlotte , NC
Introduction / Scope : The opioid crisis in the United States has necessitated monitoring of opioids in biological fluids by many state health laboratories . Urine is a common matrix for analysis , and labs require a simple yet efficient extraction process for both hydrolyzed and non-hydrolyzed samples . Here we describe a fully-automated , simplified extraction of opiates ( codeine , dihydrocodeine , hydrocodone , hydromorphone , morphine , 6-MAM , oxycodone , oxymorphone ) from acid-hydrolyzed urine and non-hydrolyzed urine prior to GC-MS analysis . The benefits of each approach are considered . The methods were automated using a Biotage ® Extrahera™ and supported liquid extraction columns ( ISOLUTE ® SLE +, Biotage , Charlotte , NC ).
Methods : Urine obtained from human volunteers was hydrolyzed by adding 3 drops of concentrated hydrochloric acid and incubating at 60 ° C for 20 minutes . Samples were cooled and the pH was adjusted to 9 with concentrated ammonium hydroxide . Non-hydrolyzed urine was pretreated 1:1 with 0.1 % ammonium hydroxide using the Extrahera . All samples were loaded onto SLE cartridges and eluted with 4 mL 95:5 dichloromethane : 2-propanol using the Biotage Extrahera . The elution solvent was evaporated using a TurboVap LV ( Biotage ). Samples were then reconstituted in 400 µ L of ethyl acetate and derivatized with 25 μL ethyl acetate and 25 μL BSTFA with 1 % TMCS prior to GC-MS analysis using an Agilent 7890A with QuickSwap in SIM mode ( Agilent Technologies , Santa Clara , CA ).
Results : Extraction recovery of 86 % -101 % from acid-hydrolyzed urine and 75 %– 93 % from non-hydrolyzed urine . RSD values were less than 10 % across both methods . Calibration curves from 5 , 10 , 50 , 100 , 500 , 1000 and 2000 ng / mL were had R2 values greater than 0.99 .
Conclusions : A simple , automated extraction workflow for analysis of opioids in hydrolyzed and non-hydrolyzed urine by GC-MS has been developed utilizing supported liquid extraction , ISOLUTE SLE +, and the Biotage Extrahera with good recoveries . There are advantages to both the hydrolyzed and non-hydrolyzed methodology that must be considered , based on the needs of the lab .
Presenter : Stephanie Marin , Biotage , stephanie . marin @ biotage . com
Systemic Comparison of EPA Approved Methods for the Determination of Mercury in Clean and Water Multiple Laboratories
R . Newcome , G . Henshaw , C . Theel , A . Bilgin and S . Hernandez Ruiz , Colorado Department of Health and Environment , Denver , CO
In recent decades , mercury quantification in environmental matrices has gained increased interest as it can bioaccumulate in fish and humans . It has the potential to cause kidney damage from short-term exposures at levels above the maximum contaminant level ( MCL ). US EPA has accepted various methods to determine concentrations in water bodies including EPA 245.1 , 245.2 , 245.7 , 1631E , 200.7 and 200.8 . Each of these methods are prone to interferences , and have different sensitivities and limitations . The aim of this study is to systematically compare low and high turbidity matrices via three approved EPA methods 245.1 , 245.7 , and 200.8 in three distinct laboratories at various mercury concentrations . This
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LAB MATTERS Summer 2021