A new configuration for coupling purge-and-trap/cryogenic focusing/capillary column gas chromatography with splitless injection mode

✍ Scribed by Liu, Shili ;Kang, Jiangshi ;Strother, Dennis L. ;Carley, Robert J. ;Stuart, James D.

• Publisher: John Wiley and Sons
• Year: 1989
• Tongue: English
• Weight: 470 KB
• Volume: 12
• Category: Article
• ISSN: 0935-6304
• DOI: 10.1002/jhrc.1240121203

✦ Synopsis

A new configuration for coupling a purge-and-trap unit to a capillary column gas chromatograph via a cryogenic focusing interface has been developed. In this configuration, the precolumn of the cryogenic focusing interface was inserted through the septum of a split/splitless injection port where it served as both sample transfer and carrier gas supply lines. The injection port of the gas chromatograph was modified by plugging the carrier gas and the septum purge lines. This configuration allowed for the desorption of analytes at high flow rates while maintaining low, analytical-column flow rates which are necessary for optimum capillary column operation. The capillary column flow rate is still controlled by the column backpressure regulator. Chromatograms of purgeable aromatics exhibited improved resolution, especially for early eluting components compared to those obtained by direct liquid injection using the normal splitless injection mode. Quantitative sample transfer to the analytical column afforded excellent linearity and reproducibility of compounds studied.