This project is funded by the Chemical Measurement and Imaging Program of the Division of Chemistry at the National Science Foundation. Professor Stephen Weber and colleagues at the University of Pittsburgh address limitations of liquid chromatography. The team is improving the ability of liquid chromatography techniques to distinguish one substance from another, as well as improving the ability to measure trace concentrations in a variety of samples. Chromatography is based on the principle of partitioning, the tendency of a substance to prefer an oily substance to water-based solution. The outcomes of this project include obtaining more and better information from samples with lower cost and lower environmental burden than has been previously realized. Collaborations with scientists in the fields of proteomics (for example, health, pharmaceuticals, and biochemistry research) and two-dimensional liquid chromatography (for example, pharmaceuticals, chemical industry, agriculture, and the environment) demonstrate the effectiveness of the project goals. The broader impacts are evidenced in that improvements in chromatographic processes that are useful across many fields and applications. Liquid chromatography is used in virtually every industry, for example, environmental, pharmaceutical, nutritional, forensic, toxicology, polymers, chemicals, and cosmetics. A Girl Scout merit badge project is also being developed by Dr. Weber to explore chromatography methods and its uses.
The project uses temperature control of the column to achieve greater solute focusing and to control retention in a predictable way. Retention enthalpies, which control the sensitivity of a particular compound to changes in temperature, are determined for a number of related organic compounds. These data are used to determine molecular fragment enthalpies. The temperature dependence of the retention of novel compounds are then predicted. Software to predict chromatographic behavior in the face of changing column temperature aids in chromatographic method development. The temperature control, when used to aid solute focusing, significantly improves concentration detection limits.
