Jaap de Zeeuw Offers Overview of Recent Developments in Capillary GC Columns at VSL

Jaap de Zeeuw

Jaap de Zeeuw

In September, the Dutch Metrology Institute (VSL) / NEN Committee 310158 held its 9th Annual Theme Day on Gas Analysis in Delft, The Netherlands. Restek’s Jaap de Zeeuw was invited to speak to the 70+ scientists in the audience, and he chose to discuss recent developments in the world of capillary columns for gas chromatography. Specifically, Jaap looked at the next generation of stabilized adsorption (PLOT) columns, metal column technology, the use of adsorbents with metal columns to solve application challenges, and more. Click here to download a PDF of the presentation.

As always, this year’s VSL Theme Day program featured talks from many specialists in the industry. Other areas of focus included dealing with the helium shortage, using nitrogen as a carrier gas, separating VOCs, lowering detection limits, and much more. After the content-rich day, attendees were also treated to a guided tour of the VSL laboratories, followed by additional discussion.


Application and Limitation of Using Adsorbents as Stationary Phases in Gas Chromatography for the Separation of Volatile Compounds

Author(s): Jaap de Zeeuw

Published By: Separation Science

Issue: vol. 4, issue 11

Year of Publication: 2012

Link: http://www.sepscience.com/emails/sepsci0912i2eu.pdf

Abstract:  Adsorbents have unique separation characteristics. The adsorption process allows very volatile components to be retained at higher temperatures that create easier conditions to quantify very volatile compounds. Several adsorbents have found wide application in industry. Molecular sieves are used for the separation of inert gases and porous polymers based on styrene divinylbenzene are used for the separation of the more polar compounds. These adsorption materials have also been made available in capillary columns where the retention is generated by a layer of adsorbent particles on the inside wall of a capillary. Such capillaries are called PLOT (Porous Layer Open Tubular) columns and are highly efficient. They produce high theoretical plate numbers and have high operation temperatures.

The challenge of PLOT columns is to stabilize the layer as particles can be dislodged from the layer and form restrictions. Such restrictions can be measured and the values can be used to control PLOT quality. It was also possible to apply the PLOT technology in metal columns (MXT), allowing the process type of applications to take full advantage of these developments. See reference [1] for an historical review.

Misselwitz and Rattray to Speak at the EPA’s 22nd Annual Quality Assurance Conference

Chris Rattray

Chris Rattray

Michelle Misselwitz

Michelle Misselwitz

From October 15–19, 2012, the U.S. Environmental Protection Agency (EPA) will hold its 22nd Annual Quality Assurance Conference in Region 6, Dallas, TX. Two Restek chemists, Michelle Misselwitz and Chris Rattray, will be making the trip south to present some of their latest work, including GCxGC analysis of pesticides and pharmaceutical and personal care products (PPCPs) as well as lowering detection limits for drinking water methods using large volume splitless injection (LVSI). For more details on each presentation, see below.

This free conference has been organized for years by the incredibly dedicated Charles Ritchie and is a great way to network with a wide range of colleagues and get caught up to speed on recent developments in environmental analysis. You can learn more about the Quality Assurance Conference on the EPA’s website (www.epa.gov/earth1r6/qa/index12.htm) and can also re-read Michelle Misselwitz’s blog on last year’s event (blog.restek.com/?p=3916) .

We hope to see you there!


Technical Presentations


9:30 a.m. / Session E
The QuEChERS Sample Preparation Approach and Comprehensive Two-Dimensional Gas Chromatography Time-of-Flight Mass Spectrometry for the Analysis of Pesticides in Tobacco

Michelle Misselwitz

Tobacco is a high-value production crop for the United States and ranks 6th among the amount of pesticides applied per acre in American agriculture. Even after the processing of tobacco, some pesticide residues remain on the final product. We used the Quick–Easy–Cheap–Effective–Rugged–Safe (QuEChERS) sample preparation approach to isolate pesticide residues from loose cigarette tobacco. Comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GCxGC-TOFMS) was used to determine pesticide residues in the resulting extracts.

3:00 p.m. / Session C
Analysis of Pharmaceutical and Personal Care Products and Other Emerging Environmental Contaminants in Water Using a Highly Efficient GCxGC-TOFMS System

Michelle Misselwitz

Comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GCxGC-TOFMS) is a powerful multidimensional approach to sample analysis that is unmatched by traditional one-dimensional chromatography. By operating the system to maximize efficiency in both the first and second dimension, GCxGC-TOFMS has the ability to detect, identify, and quantify or semi-quantify an unlimited number of target, non-target, and unknown compounds (including emerging compounds of concern) with full mass spectra and sub- to low-pg sensitivity. Using this technique, water samples were collected from the urban river in Las Vegas to analyze a large number of pharmaceutical and personal care products and other emerging environmental contaminants.

4:00 p.m. / Session D
Achieving Lower Detection Limits for Multiple Drinking Water Methods Using Large Volume Splitless Injections on an Unmodified Split/Splitless Injection Port

Chris Rattray
For more information, email Chris Rattray.

Utilizing a large volume splitless injection is advantageous for many reasons. Some of these include shipping and extracting significantly smaller sample sizes, reducing extract concentration, or decreasing limits of detection for trace-level analysis in drinking water. The drawback for many is that large volume injections typically require a specialized injection port. However, with concurrent solvent recondensation-large volume splitless injection (CSR-LVSI), a large volume injection can be achieved on an unmodified Agilent split/splitless injection port. Here we analyzed multiple drinking water methods using CSR-LVSI on an Agilent 7890/5975C GC-MSD and injected up to 10 µL to achieve lower detection limits.

QuEChERS: A Primer

Author(s): Julie Kowalski and Jack Cochran
Restek Corporation

Published By: Separation Science

Issue: vol. 4, issue 12

Year of Publication: 2012

Link: http://www.sepscience.com/Techniques/Sample-Prep/Articles/865-/QuEChERS-A-Primer

For the full print issue, visit http://www.sepscience.com/docs/Bespoke/Editions/SepSci/Sepsci1012eu.pdf?utm_source=iContact&utm_medium=email&utm_campaign=eLearning%20Newsletter%20-%20Europe%20Sep%20Sci&utm_content=

Abstract: Quick, Easy, Cheap, Effective, Rugged and Safe, the QuEChERS (pronounced “catchers”) method is based on work done and published in 2003 by Anastassiades et al. QuEChERS was developed as an extraction method for pesticides in fruits and vegetables, coupled with a cleanup method that removes sugars, lipids, organic acids, sterols, proteins, pigments, and excess water. QuEChERS involves two simple steps: first, a homogenized sample is extracted and partitioned using an acetonitrile and salt solution, then, the supernatant is cleaned using a dispersive solid-phase extraction (dSPE) technique. This QuEChERS approach offers a user-friendly alternative to traditional liquid-liquid and solid-phase extractions.