Liquid Chromatography at the Extreme: Ultra-Pressure, High Temperature, and Ultra-Fast

Pittcon 2007 opened with a bang here in Chicago, albeit a snowy bang. All the liquid falling outside, whether in rain, snow, or ice form, was nothing compared to the liquid chromatography sessions happening within the halls of McCormick Place, and none was more fitting for the extreme weather conditions outside than the session entitled “Liquid Chromatography at the Extreme: Ultra-pressure, High Temperature and Ultra-fast.”

Brian A. Jones, Mark J. Hayward, and Qing P. Han opened the session by presenting their thoughts on using temperature as a tool to increase resolution per unit time, highlighted by their theory on different approaches using small particle packing materials in conjunction with the use of pumps that can achieve pressures exceeding 10,000 psi.

That presentation was followed by “Combining Elevated Temperature and Ultra-high Pressure to Improve Chromatographic Separations” by Eric S. Grumbach, Diane M. Diehl, and Jeffrey R. Mazzeo, discussing the effect of small particles, elevated temperature and higher pressures on chromatographic separations.

Next up was “Benefits of Elevated Temperature High Speed HPLC” by William J. Long, Cliff Woodward, and John Henderson, focusing on column stability, reproducibility of analysis, temperature control detector data collection speed and noise over a temperature range that can be met with the Agilent 1200, as well as demonstrate some of the benefits of High Temperature High Speed HPLC.

The last presentation before recess was by Dwight R. Stoll, Peter W. Carr, Adam P. Schellinger, and Xiaoli Wang. This quartet’s discussion was entitled “Revisiting Gradient Elution HPLC as a Tool for Ultra-Fast Liquid Chromatography Analysis.” Their talk entailed an in-depth conversation on the necessary slowness of gradient elution HPLC, and that the time required re-equilibration is limited mainly by instrument design but not by the column's behavior, and that highly reproducible retention can often be obtained after re-equilibrating the column with as little as one column volume of the initial mobile phase.

After the recess, Mark J. Hayward got things restarted with his presentation “The Crucial Role of Diffusion in Fast Gradient Reversed PhaseLiquid Chromatography,” followed by Eric S. Grumbach, Diane M. Diehl, and Jeffrey R. Mazzeo discussing another topic, this time called “Automated UPLC Methods Development: Monitoring Selectivity Change by Controlling Stationary Phase, Organic Modifier, pH and Temperature” about the chromatographic effect of chemical factors on retentivity and selectivity.

To finish out the session, Xiaowei Sun and Loren Wrsiley discussed a systematic approach to covert UPLC conditions to traditional HPLC conditions, followed shortly thereafter by Rachel Lieberman, James W. Jorgenson, Joseph W. Thompson giving their presentation entitled “Characterization of Capillary Columns Packed with Micron Particles for Ultra- high Pressure Liquid Chromatography,” finding that columns packed with purified particles give more efficient plate heights when compared to columns packed with unpurified particles.

So while the various forms of liquid outside may have been less than pleasant, the liquid chromatography discussions at Pittcon continue to be extremely informative and revealing.