What are some examples of preparative GC applications? According to R.P.W. Scott in Gas Chromatography (1), ?[t]here are a number of unique problems associated with preparative gas chromatography. Firstly, it is difficult to recycle the mobile phase and thus large volume of gas are necessary. Secondly, the sample must be fully vaporized onto the column to ensure radial distribution of the sample across the column. Thirdly, the materials of interest are eluted largely in a very dilute form from the column and therefore must be extracted or condensed from the gas stream which is also difficult to achieve efficiently.?
An LCGC reader recently submitted the following question:
What are some examples of preparative GC applications?
According to R.P.W. Scott in Gas Chromatography (1), “[t]here are a number of unique problems associated with preparative gas chromatography. Firstly, it is difficult to recycle the mobile phase and thus large volume of gas are necessary. Secondly, the sample must be fully vaporized onto the column to ensure radial distribution of the sample across the column. Thirdly, the materials of interest are eluted largely in a very dilute form from the column and therefore must be extracted or condensed from the gas stream which is also difficult to achieve efficiently.”
Preparative GC has been used for a variety of applications, including odorants in white wine (2), amino acids in tissue hydrolysates (3), polycyclic aromatic hydrocarbons (4), cockroach sex pheromone (5), and essential oil constituents (6).
(1) R.P.W. Scott, Gas Chromatography, http://www.chromatography-online.org/GC/Preparative-Gas-Chromatography/rs60.html.
(2) H. Shiratsuchi, and H. Matsusaki, Aroma Research 6(2) 188â194 (2005).
(3) K. Smith, C.M. Scrimgeour, W.M. Bennet, and M.J. Rennie, Biol. Mass Spec. 17(4), 267â273 (1988).
(4) M. Mandalakis and Ã. Gustafsson, J. Chromatography A 996(1-2), 163â172 (2003).
(5) S. Nojima, C. Schal, F.X. Webster, R.G. Santangelo, and W.L. Roelofs, Science 307(5712), 1104â1106 (2005).
(6) M. Mekem Sonwa and W.A. König, Phytochemistry 56(4), 321â326 (2001).
Questions?
LCGC technical editor Steve Brown will answer your technical questions. Each month, one question will be selected to appear in this space, so we welcome your submissions. Please send all questions to the attention of "Ask the Editor" at lcgcedit@lcgcmag.com We look forward to hearing from you.
Determining Neurotransmitters in Spinal Cords with UHPLC
February 18th 2025Researchers at Jilin University (Changchun, China) developed a highly sensitive, rapid, and accurate method for analyzing neurotransmitters (NTs) in rat spinal cord tissue. Ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS) in conjunction with ultra-ionic liquid dispersive liquid-liquid microextraction (UA-MIL-DLLME) were used to extract NTs for analysis.
The Next Frontier for Mass Spectrometry: Maximizing Ion Utilization
January 20th 2025In this podcast, Daniel DeBord, CTO of MOBILion Systems, describes a new high resolution mass spectrometry approach that promises to increase speed and sensitivity in omics applications. MOBILion recently introduced the PAMAF mode of operation, which stands for parallel accumulation with mobility aligned fragmentation. It substantially increases the fraction of ions used for mass spectrometry analysis by replacing the functionality of the quadrupole with high resolution ion mobility. Listen to learn more about this exciting new development.
Revolutionizing LC-MS with Next-Gen Separation for Cyclic Peptide Analysis
February 17th 2025Cyclic peptides, known for their stability and high specificity, are promising therapeutic agents in the fight against cancer, infections, and autoimmune diseases. However, developing effective cyclic peptides presents numerous challenges, including poor pharmacokinetics, efficacy, and toxicity. Traditional methods like liquid chromatography tandem-mass spectrometry (LC-MS/MS) often struggle with resolving isomeric linear peptide metabolites, posing significant risks in safety, efficacy, and regulatory approval. In this paper, Komal Kedia, PhD, will share how she leveraged MOBIE’s high-resolution ion mobility-mass spectrometry (IM-MS) system to achieve a 72% reduction in run times, 200% greater resolving power, and enhanced accuracy in identifying “soft spots” prone to enzymatic degradation.