The answer to the following question was supplied by LCG Europe's "GC Connections" columnist John Hinshaw.
The answer to the following question was supplied by LCGC Europe's “GC Connections” columnist John Hinshaw.
Q: What are the main causes of GC column degradation or decline in performance?
John Hinshaw: There are four main causes of GC column degradation and performance decline.
First, columns are degraded by the build-up of nonvolatile sample residues that interact with target analytes to cause peak tailing, catalytic decomposition, and ultimately loss of separation. Proper sample preparation, the use of a retention gap, and inlet liner maintenance will help alleviate this problem. Trimming the beginning of a contaminated column can recover some performance. Headspace sampling, when possible, completely eliminates this problem.
Second, chemically active substances in the sample such as derivatization reagents and their by-products can degrade the stationary phase and will lead to significant performance losses. Careful choice of derivatization reagents and avoidance of excessive amounts will help reduce this effect. Some stationary phases are less susceptible to these effects.
Third, the presence of oxygen in the carrier gas from leaks or poor quality gas cylinders will degrade some stationary phases, such as Carbowax and bonded Carbowax types. Attention to carrier gas quality, the use of fresh oxygen filters, and leak-free connections will ensure a longer lifetime for these columns.
Fourth, excessively high operating or conditioning temperatures will age a column prematurely. Never exceed the maximum operating temperature when performing separations, and never exceed the recommended conditioning temperature and duration.
LC–MS/MS-Based System Used to Profile Ceramide Reactions to Diseases
April 26th 2024Scientists from the University of Córdoba in Córdoba, Spain recently used liquid chromatography–tandem mass spectrometry (LC–MS/MS) to comprehensively profile human ceramides to determine their reactions to diseases.
High-Throughput 4D TIMS Method Accelerates Lipidomics Analysis
April 25th 2024Ultrahigh-pressure liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS) had been previously proposed for untargeted lipidomics analysis, but this updated approach was reported by the authors to reduce run time to 4 min.