In this project funded by the Chemical Measurement and Imaging program of the Chemistry Division, Professor Purnendu Dasgupta and students at the University of Texas at Arlington are developing a new generation of small portable analyzers that can be used in the field. This project uses the Grant Opportunities for Academic Liaison with Industry (GOALI) program of the NSF to form an industry alliance with a leading ion chromatography (IC) manufacturer, Thermo Fisher Dionex (Sunnyvale, CA). Several students will have an opportunity to intern at the manufacturer's facility and industry scientists will co-supervise students towards a building miniature, field-portable ion chromatographs of low footprint and low power. The broader impacts are addressed through the development of a field deployable instrument that will be used in many applications, and through undergraduate and graduate student education and training that includes unique and extensive industrial interactions.
This project has two separate broad goals: While most anion analyses today are carried out by ion chromatography, the equipment is still too heavy and consumes too much power to be easily deployed in the field. This project seeks to develop a small, portable, low power consumption ion chromatograph instrument for field deployment. Rather than packed columns, a suppressed open tubular (OT) IC is envisioned where the column will contain an integral suppressor and admittance detector for fully functional gradient-capable, suppressed IC. Further, a second admittance detector will be present. Before this detector, a base will permeate through the wall and mix with the first detector effluent; this principle is known to enable detection of very weak acid anions, not presently possible. The second goal is to explore scanning detection in liquid and ion chromatography, using a variety of detectors and separation modes. Glass, silica and polymer columns are transparent to several types of detectors. A scanning platform provides an inexpensive high-resolution means to look at separations occurring inside columns as they occur. The net result is that one can look at separations in real time and, in principle, provide automated feedback to eluent composition to improve separations. The wealth of data generated during multiple scans will enable accurate quantification actually before complete separation occurs. Scanning detection visualizes what did not elute and provides a diagnostic of column health. Finally, in gradient elution, the three dimensional map of time location and speed of an analyte is expected to provide an identification marker that is intrinsically chromatographic and not detector-dependent.
