Novel Technologies for Portable Capillary Chromatography
Milton L. Lee, Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602 USA
While performance is the most important quality of analytical chemistry instrumentation, other characteristics are growing in importance, including portability, simplicity and robustness. Most current chromatographic instrumentation has been designed for stationary use on a laboratory bench. The trend toward miniaturization has allowed increased portability, even if this means only movement within the laboratory to facilitate sample analysis or coupling to other instruments. With respect to both GC and LC, column robustness and interfacing have become the most difficult challenges, especially when the preeminent requirement is to retain high chromatographic performance. Advances in resistive heating technologies and microchip column formats have been made to address requirements for portable GC, but interfacing and temperature uniformity can be a challenge. In parallel, nano-flow capillary columns have been developed for LC, but minimizing detrimental extra-column volumes in connections and developing sensitive detection for small columns are difficult challenges. Advancements in microchip thermal gradient GC and compact nano-flow LC will be described. Highlights include microchip column technologies with high temperature seals for thermal gradient GC, and “plug-and-play” leak-tight column cartridges for nanoflow capillary LC. Serial column arrangements with dual-wavelength on-column UV-absorption detection will be described for positive target analyte detection.