The drive toward green and sustainable chemistry has increased significantly over the past several years. More recently, an increased focus on “greening” analytical workflows has been observed. From sample preparation to detection, every step must be critically evaluated to conserve energy and minimize environmental impact and waste.
Hydrophilic interaction liquid chromatography (HILIC) often utilizes a high percentage of acetonitrile in the mobile phase. Although acetonitrile is not the worst solvent in terms of sustainability, other solvents are considered to be more environmentally friendly, less toxic, and renewable. In this presentation we report on our efforts to replace or reduce acetonitrile usage in HILIC mode with more sustainable solvent systems. The results of direct acetonitrile replacement by various solvents are presented along with a variety of additional approaches, such as cosolvent implementation, to minimize acetonitrile where the usage of green solvents alone generated poor performance. In addition, alternative modes of chromatography are also discussed that may provide the retention and selectivity offered by HILIC, but in a more sustainable manner. Throughout the effort, underlying retention mechanisms are monitored and interpreted for greater overall chromatographic insight.

