Greener Approaches to Chemical Separations

The use of portable and compact instrumentation has expanded the possibilities of integrating capillary-scale LC techniques into realms typically dominated by analytical-scale methodology. Low-volume detector flow cells and UV-LED light sources allow for improvements in absorbance detection for columns with internal diameters in the 0.1 – 0.3 mm range. Compact single-quad mass spectrometers with integrated vacuum systems also allow for LC-MS measurements when combined with compact capillary LC platforms. Progress on the use of this technology to solve challenges that exist using typical benchtop instrumentation in pharmaceutical and clinical laboratories will be discussed. Separation methods utilizing mobile phases containing supercritical fluids can also provide a greener approach to chemical analysis. As SFC becomes more relevant for metabolomic studies based on its compatibility in separating compounds with a wide range of polarities, strategies to improve sensitivity for less abundant species must be developed. New analyte derivatization approaches used to improve the signal of organic acid compounds in SFC-MS and nano-spray SFC strategies to increase overall MS signal to meet this need will be described.