ASE 150 & 350 Instrument Parts Are Now Available!

Replacement Parts & Accessories for ASE® SystemsWe are pleased to announce the release of extraction cell caps and extraction cell bodies for accelerated solvent extraction (ASE) 150 and 350 instruments. These new products expand our ASE selection to cover the 100/300, 200, and 150/350 series as part of our drive to offer high-quality, affordable parts and accessories for ASE instrumentation. In addition to caps and cells, Restek is also your source for PEEK washers, filters, replacement parts, vials, and tools.

You will find our entire line of ASE® parts at

The Importance of Gas Chromatography in the Impurity Testing of Process Gases Used in the Pharmaceutical Industry

Author(s): Zafer Bayram and Hakan Dibek
Ant Teknik Cihazlar

Published By: Turkchem Magazine

Issue: Jan./Feb.

Year of Publication: 2013

Abstract: In the pharmaceutical industry, gas chromatography (GC) is routinely used for analyzing volatile and semivolatile compounds. While GC is frequently employed for quantitative reporting of residual solvents in raw materials and finished products, this technique is also now gaining popularity for the impurity testing of process gases, such as nitrogen. Molecular sieve PLOT capillary GC columns are the column of choice for analyzing these gases, due to their ability to separate light components. In this article, the authors provide an overview of process gas testing and example chromatography specifically for the pharmaceutical industry.

 Acknowledgment(s): Chromatogram supplied by Restek Corporation.

Ghost Peaks in Gas Chromatography Part I: The Carrier Gas and Carrier Gas Lines

Author(s): Jaap de Zeeuw
Restek Corporation

Published By: Separation Science

Issue: vol. 5, issue 2

Year of Publication: 2013


For the full print issue, visit

Abstract: We get always a number of inquiries from customers that see peaks show up in their chromatogram when they do not inject them. There are several sources for these “ghost peaks,” which we will discuss in several articles. Part I focuses on the carrier gas and carrier gas lines.

Krone Advances to State Science Fair


8th grader Liesl Krone presents her research.

Restek is pleased to congratulate Liesl Krone, an 8th grader at Acton Middle School in Granbury Texas, whose science fair project recently advanced to state-level competition. Her project entitled “What Pesticides Have You Eaten Today” will be presented at the ExxonMobil Texas Science and Engineering Fair in San Antonio, Texas.

Liesl became interested in food safety after hearing news reports on food quality issues. She loves fruit and wondered if she was consuming pesticides along with beneficial nutrients. To answer that question, Liesl tested the pesticide residue concentrations of a variety of organic and conventionally grown fruits. Liesl’s experiment paired a QuEChERS sample extraction procedure with LC-MS/MS analysis.

One of the most interesting things Liesl discovered was that while peeling fruits reduced pesticide levels, it did not eliminate them completely. She also found that it is possible to consume fruit in the U.S. that contains pesticides that are not registered for use in this country when she detected Fenpryoximate in imported grapes. She concluded that, while fruit is still a better choice than junk food, research like this plays a valuable role in helping people understand exactly what is going into their bodies.

This project was made possible by instrument time at Analytical Food Labs in Grapevine, Texas; Q-sep™ QuEChERS products from Restek; and scientific input from André Schreiber at AB SCIEX.

Congratulations, Liesl, and good luck at the state competition!