There is No Time to Waste: Low-Pressure Gas Chromatography–Mass Spectrometry is a Proven Solution for Fast, Sensitive, and Robust GC–MS Analysis

Author(s): Steven J. Lehotay2, Jaap de Zeeuw1, Yelena Sapozhnikova2, Nicolás Michlig2,3, Jana Rousova Hepner1, and Joseph D. Konschnik1

1. Restek Corporation, 2. Eastern Regional Research Center at the U.S. Department of Agriculture, 3. Programa de Investigación y Análisis de Residuos y Contaminantes Químicos (PRINARC), in the Facultad de Ingeniería Química at the Universidad Nacional del Litoral

Published By: LCGC North America 38(8)

Year of Publication: 2020

Link: https://cdn.sanity.io/files/0vv8moc6/chroma/f562afa926baa1c61c935270836a3374f513bb14.pdf#page=33

Abstract: Low-pressure gas chromatography (LPGC) has been known to be advantageous compared to standard GC since Giddings first described the concept in 1962, but a practical solution for its use eluded analytical chemists until the year 2000, when de Zeeuw fashioned a simple guard column restrictor concept to maintain positive inlet pressure for a wide-bore analytical column under vacuum. Initially introduced as rapid mass spectrometry (MS), de Zeeuw’s invention made LPGC practical in nearly any GC application using MS for detection. Lehotay and associates have demonstrated the advantageous features, excellent performance, and practical utility of LPGC–MS in dozens of publications since 2001. In our experience, LPGC–MS is the most practical and beneficial fast-GC technique available to achieve <10 min analyses in applications that typically take 20–40 min. Sample capacity and column robustness are increased greatly using LPGC to permit large-volume injection with standard inlets without column maintenance, and, because vacuum conditions generate taller and narrower peaks that are still suitable for standard MS data acquisition rates, sensitivity is also increased. Furthermore, enhanced selectivity of detection using modern MS tools and software compensate for reduced chromatographic peak capacity. In our view, LPGC–MS should be the first option for evaluation in many GC–MS applications to provide fast, sensitive, and robust analyses.

Routine LC Maintenance: Simple Steps to Preventing Unexpected Downtime

Published By: Restek Corporation

Year of Publication: 2020

Link: https://www.restek.com/Technical-Resources/Technical-Library/General-Interest/general_GNAR3214-UNV

Abstract: Routine LC maintenance will keep your instrument performing well and minimize downtime for unexpected repairs. In this article, we explore how to develop an effective preventative maintenance plan.

Get a Quicker Cleanup: Resprep SLE Cartridges and 96-Well Plates

Dilute-and-shoot is only effective when you are working with relatively clean matrices—complex biological samples, such as whole blood, require a cleanup step or your results may be inaccurate. But, if your sample matrix does not require the intensive cleanup power of SPE or liquid-liquid extraction, why spend time and resources on a complex procedure? For many compounds, excellent analytical results can be obtained with a quick and easy SLE cleanup. New Resprep SLE cartridges and 96-well plates effectively remove matrix components, such as proteins, phospholipids, and salts, in three simple steps: just load, wait 5 minutes, then elute. Suitable for a wide range of matrices and analytes, Resprep SLE cleanup is a quick, efficient, and fully automatable sample preparation solution.
Get details at www.restek.com/ResprepSLE

Novel Stationary Phase for Comprehensive PFAS Analysis: Ultrashort-Chain (C2, C3), Alternative, and Legacy Compounds

Published By: Restek Corporation

Year of Publication: 2020

Link: https://www.restek.com/Technical-Resources/Technical-Library/Environmental/env_EVFA3197A-UNV

Abstract: In this fast, isocratic LC-MS/MS analysis, Raptor Polar X columns provide proper chromatographic retention of TFA and other small, polar ultrashort-chain PFAS as well as short- and long-chain PFAS.

Simple Large Volume Injection Method for Trace-Level Glyphosate in Bottled Drinking Water

Published By: Restek Corporation

Year of Publication: 2020

Link: https://www.restek.com/Technical-Resources/Technical-Library/Environmental/env_EVFA3196-UNV

Abstract: Trace-level detection of glyphosate can be achieved without complex derivatization or ion paining by using direct large volume injection of water on a Raptor Polar X column.

Raptor Polar X: Separate a Wide Variety of Polar Analytes with a Novel Hybrid Stationary Phase

Published By: Restek Corporation

Year of Publication: 2020

Link: https://www.restek.com/Technical-Resources/Technical-Library/General-Interest/gen_GNSS3195-UNV

Abstract: The unique hybrid phase in Raptor Polar X columns balances HILIC and ion exchange retention modes, making it ideal for analyzing a wide range of polar compounds, especially when coupled with mass spectrometry.

Separate a Wide Variety of Polar Analytes with New Raptor Polar X Columns

Analyzing polar compounds using liquid chromatography has historically been a challenge. Poor retention and peak shape, complex mobile phases that may not be MS-friendly, long equilibration times, low sensitivity, and sample derivatization are all complications that reduce lab efficiency and productivity. However, new Raptor Polar X columns reliably retain and efficiently separate a broad range of polar analytes using a unique stationary phase that balances two retention mechanisms: HILIC and ion exchange. This hybrid phase is ideal for analyzing acidic, basic, and neutral polar compounds without time-consuming derivatization or complex ion pairing, and it is especially compatible with mass spectrometry. Easy changes to mobile phase conditions allow analysts to switch between modes and selectively tune retention for the compounds of interest without needing long equilibration times. Simplify the analysis of polar compounds with the resolving power of Raptor Polar X columns from Restek.

Learn more about Raptor Polar X columns at www.restek.com/PolarX

About Raptor SPP LC Columns:
Restek chemists became the first to combine the speed of superficially porous particles (also known as SPP or “core-shell” particles) with the resolution of highly selective USLC technology. This new breed of chromatographic column allows you to more easily achieve peak separation and faster analysis times without expensive UHPLC instrumentation.

Learn more about Raptor LC columns at www.restek.com/raptor

Faster Trace-Level Analysis of Acrylamide in Drinking Water and Food

Now available in two column formats for optimal application-specific performance, Allure Acrylamide LC columns enable you to meet method requirements for food and drinking water quickly and easily. Unique column chemistry reliably separates acrylamide from matrix interferences, and our new format for large volume injection lets you reach sensitivity requirements without time-consuming SPE preconcentration. The new 150 x 3.0 mm column provides an optimized balance of larger capacity and MS-friendly flow rates for large volume injection of drinking water samples while the original 50 x 2.1 mm format delivers faster analysis times and fewer column changes for both food and drinking water when used with SPE sample preparation. Pair with Restek guard columns and analytical reference standards to ensure data quality even down to low ppt levels in sample matrix.

Developed to withstand 100% aqueous mobile phases and elute coextracted matrix components rather than strongly retaining them, Restek Allure Acrylamide guard and analytical columns deliver the same robust performance injection to injection and column to column. Our stringent manufacturing procedures and rigorous quality testing ensure that when it does come time to replace your Allure Acrylamide column, you will get the same great chromatographic performance with the new column that you relied on with the old one.

www.restek.com/acrylamide

LC-MS/MS Analysis of Acrylamide in Drinking Water Using Large Volume Injection

Published By: Restek Corporation

Year of Publication: 2020

Link: https://www.restek.com/Technical-Resources/Technical-Library/Environmental/env_EVAR3184-UNV

Abstract: In this work, we share a method for the analysis of acrylamide in drinking water at low ppt levels using large volume injections directly into an LC-MS/MS.

Tips for Preparing Calibration Curve Standards and Avoiding Sources of Error

Author: Landon Wiest

Published By: Restek Corporation

Year of Publication: 2020

Link: https://www.restek.com/Technical-Resources/Technical-Library/General-Interest/gen_GNAR3169-UNV

Abstract: When preparing calibration curve standards, minimizing sources of error is vital for obtaining accurate quantitative results. This article shares best practices relating to equipment, chemical interactions, and workflow solutions that will help ensure accurate and precise analytical results.