There is no Time to waste: low-pressure gas chromatography-mass spectrometry is a proven solution for fast, sensitive, and robust GC-MS analysis

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.