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Pittcon 2023

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18-22 March, Philadelphia, PA, U.S.

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Live Demonstrations: Booth 2218

EZLC Chromatogram Modeler Software 

See how to create LC methods in minutes with free, easy-to-use EZLC chromatogram modeling software.
  • Monday: 2:00 p.m.
  • Tuesday: 11:30 a.m.
  • Wednesday: 11:30 a.m.

Short Course

 

Practical Maintenance and Troubleshooting in Gas Chromatography        

In gas chromatography, 90% of the trouble experienced is happening in the injection system. In this half-day course, we will discuss the maintenance challenges for split and splitless injection techniques that are used in GC. We will zoom in on carrier gas choice and purity, tubing, connections, septa, ferrules, seals, liners, column-coupling, installation, and column maintenance. We will also discuss column operation/optimization and extending column lifetime.

Information:
 8:30 a.m. - 12:30 p.m.
 21 March 2023
Authors:
  1. Jaap de Zeeuw
Affiliations:
Restek Corporation
Presenters:
Jaap de Zeeuw
 

Oral Presentation

 

Single-Column Solution for Ultrashort-Chain and Short-Chain (C1, C2, C3, C4) PFAS Analysis by LC-MS/MS

While many PFAS testing standards focus on the analysis of short- to long-chain length compounds by LC-MS/MS technique employing reversed-phase liquid chromatography, ultrashort-chain PFAS compounds are frequently found in our environment, and their high concentration and frequency of occurrence are concerning. Due to their chain length and chemical structure, they are categorized as PMOC (polar mobile organic compounds) and reversed-phase column chemistry is incapable of retaining them. Lack of analyte retention and reproducibility are common challenges in PMOC analysis. In this presentation, we will go through the method development process for ultrashort-chain PFAS analysis and show the data with real samples. This single column approach has shown great precision and accuracy utilizing conventional LC-MS/MS system.

Information:
 9:10 a.m. - 9:30 a.m.
 20 March 2023
Authors:
  1. Mike Chang
Affiliations:
Restek Corporations
Presenters:
Mike Chang
 
 

The Development of a Virtual Liquid Chromatography Method Development Tool

The development and optimization of liquid chromatography (LC) separations can be time-consuming and costly, often requiring a number of steps, including literature research, column selection, method scouting, method development, and method optimization. In an effort to eliminate these steps, an instrument-free, software modeling tool was developed that gives users the ability to select compounds from a database and instantly model a separation on different column phases.
 
Optimization of the chromatogram model can be performed while maintaining critical pair separations by adjusting parameters, such as instrument/system effects (e.g., dwell volume and extra column volume); mobile phase preferences; number of gradient steps; and more.  The first version contains an initial library of approximately 250 Drugs of Abuse (DoA) with plans to expand by adding additional compounds and more utility.
 
The initial platform build was completed by validation on a single column dimension by monitoring a set of compounds, collecting retention times using a fast/slow gradient; 30°C/60°C temperature points; and acetonitrile/ methanol mobile phases. The modeler was evaluated over four increasingly more complex stages of verification. In the final, most complex stage, new compounds not previously part of the initial DoA library were added and then compared by testing two different column dimensions, two different columns lengths, two different mobile phases, two different stationary phases, three different gradients programs, and three different temperatures against modeled retention time values. Some additional data outside of these runs were also collected for the development of a semi-empirical correction factor that was used to improve modeling accuracy and test the viability of adding future compounds to existing libraries.
 
To represent a typical MRM window, an acceptance criteria of +/- 15 seconds was. In the most complex portion of the verification, 704 retention time data points were collected in total for the 25 compounds used in the evaluation. Only 13 data points exceeded the +/- 15 second window with no compounds missing acceptance criteria by more than five seconds. The overall pass rate was 98.2%.  
 
The modeler delivers a fast, no-cost starting point for LC method developers, novice, and expert, who either lack the expertise, or the time, to develop or optimize separations quickly and accurately. This novel, virtual method development software can improve turnaround time, increase throughput to existing methods, and offer an on-demand consultative user experience.
Information:
 3:25 p.m. - 3:45 p.m.
 21 March 2023
Authors:
  1. Melinda Urich
Affiliations:
Restek Corporation
Presenters:
Melinda Urich
 

Poster Presentation

 

Chiral Separation and Optimization on Substituted β-Cyclodextrin Columns

The development and optimization of liquid chromatography (LC) separations can be time-consuming and costly, often requiring a number of steps, including literature research, column selection, method scouting, method development, and method optimization. In an effort to eliminate these steps, an instrument-free, software modeling tool was developed that gives users the ability to select compounds from a database and instantly model a separation on different column phases.
 
Optimization of the chromatogram model can be performed while maintaining critical pair separations by adjusting parameters, such as instrument/system effects (e.g., dwell volume and extra column volume); mobile phase preferences; number of gradient steps; and more.  The first version contains an initial library of approximately 250 Drugs of Abuse (DoA) with plans to expand by adding additional compounds and more utility.
 
The initial platform build was completed by validation on a single column dimension by monitoring a set of compounds, collecting retention times using a fast/slow gradient; 30°C/60°C temperature points; and acetonitrile/ methanol mobile phases. The modeler was evaluated over four increasingly more complex stages of verification. In the final, most complex stage, new compounds not previously part of the initial DoA library were added and then compared by testing two different column dimensions, two different columns lengths, two different mobile phases, two different stationary phases, three different gradients programs, and three different temperatures against modeled retention time values. Some additional data outside of these runs were also collected for the development of a semi-empirical correction factor that was used to improve modeling accuracy and test the viability of adding future compounds to existing libraries.
 
To represent a typical MRM window, an acceptance criteria of +/- 15 seconds was. In the most complex portion of the verification, 704 retention time data points were collected in total for the 25 compounds used in the evaluation. Only 13 data points exceeded the +/- 15 second window with no compounds missing acceptance criteria by more than five seconds. The overall pass rate was 98.2%.  
 
The modeler delivers a fast, no-cost starting point for LC method developers, novice, and expert, who either lack the expertise, or the time, to develop or optimize separations quickly and accurately. This novel, virtual method development software can improve turnaround time, increase throughput to existing methods, and offer an on-demand consultative user experience.
Information:
 1:00 p.m. - 3:00 p.m.
 20 March 2023
Authors:
  1. Jaap de Zeeuw, Kristi Sellers, Whitney Dudek-Salisbury
Affiliations:
Restek Corporation
Presenters:
Jaap de Zeeuw
 
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PDF
 

Development of a Semivolatile Column Optimized for the Analysis of Hazardous Waste

Analyzing basic, neutral, and acidic semivolatile environmental pollutants, such as those found in U.S. EPA 8270 at increasingly lower levels of detection, puts demands on the entire analytical system. One of the greatest challenges is maintaining system performance following repeated injections of highly contaminated samples. The goal is to develop a column tuned for PAH selectivity while maintaining the same elution profile labs expect from other silarylene “5-type” columns along with improved lifetime.
 
This presentation will review the details of the lifetime study results using contaminated extracts and will highlight the advantages of this column using a new deactivation and stationary phase.
Information:
 1:00 p.m. - 3:00 p.m.
 20 March 2023
Authors:
  1. Chris English, Corby Hilliard, Christopher Rattray, Kristi Sellers, Whitney Dudek-Salisbury, Brian Salisbury
Affiliations:
Restek Corporation
Presenters:
Chris English
 
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PDF
 

Cannabinoid Extraction Efficiency for Potency Analysis: An In-Depth Look at Multiple Techniques

There are many different extraction techniques on the market and oftentimes new labs are confused as to where to begin and which technique would best suit their needs. In this study, six different extraction methods were investigated to determine overall efficiency as well as sample preparation cost and sample preparation time. Two types of chemovars were used for the study, CBD and CBG, to ensure extraction efficiency is comparable across different varieties. Due to its robust nature, a UV-Vis was used and monitored at 228 nm. All data was obtained by using a Raptor ARC-18 2.7 µm, 150 x 4.6 mm column with accompanying 5 x 4.6 mm EXP guard. A total of sixteen cannabinoids were monitored under 25:75 isocratic conditions consisting of mobile phase A 5 mM Ammonium formate in water with 0.1% formic acid and mobile phase B of 0.1 % formic acid in acetonitrile, for a total cycle time of 9 minutes.
Information:
 10:00 a.m. - 12:00 p.m.
 21 March 2023
Authors:
  1. Melinda Urich
Affiliations:
Restek Corporation
Presenters:
Melinda Urich
 
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PDF
 

Separation and Quantitation of Total Plasma Homocysteine and Methylmalonic Acid by LC-MS/MS Analysis

Homocysteine and methylmalonic acid are important biomarkers used in the diagnosis of a number of cobalamin disorders. Some of these disorders include hyperhomocysteinemia, homocystinuria, methylmalonic acidemia, and megaloblastic anemia. For proper diagnosis of cobalamin disorders, it is important to quantitate the levels of these analytes. When using homocysteine for quantitation, it is best to use total plasma homocysteine. This includes all of the oxidized and bound forms of the homocystine dimer. In order to calculate total plasma homocysteine, often derivatization is used. In the sample preparation used for this analysis, a sulfhydryl reagent called “dithiothreitol,” or DTT, is used. This eliminates the need for lengthy derivatization in the sample preparation and works effectively in converting all of the dimer forms of homocystine to the monomer form, homocysteine. When analyzing methylmalonic acid, it is important to keep in mind that methylmalonic acid has a naturally occurring isomer, succinic acid. In order to quantitate methylmalonic acid accurately, there needs to be chromatographic separation of these two isomers. This work includes a quick sample preparation using protein precipitation and the use of DTT. The rapid, 4-minute LC-MS/MS method allows for resolution of all analytes, including the two isomers. This method showed reproducible retention times and selectivity over the course of testing as well as good precision and accuracy for all calibrators, quality controls, and standard addition plasma samples.

Information:
 10:00 a.m. - 12:00 p.m.
 22 March 2023
Authors:
  1. Samantha Herbick, Justin Steimling
Affiliations:
Restek Corporation
Presenters:
Samantha Herbick
 
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PDF