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Professor's work results in patent

Tuesday, December 18, 2012

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Media Contact: Traci Peterson

A University of Texas at Arlington chemist’s work to develop a more efficient, effective way of measuring ions in solution has led to a new device in the scientific marketplace that could improve water quality testing and manufacturing methods.

Dr. Purnendu Dasgupta

Dr. Purnendu Dasgupta

Purnendu “Sandy” Dasgupta invented the charge detector for ion chromatography, along with Bingcheng Yang, a member of his research group, and Kannan Srinivasan, technical director for Thermo Fisher Scientific Inc. The U.S. Patent office recently assigned a patent for the new technology to the UT System Board of Regents and Dionex Corporation, which is based in Sunnyvale, Calif.  Thermo Fisher is Dionex’s parent company.

“The fact that ions carry a charge has been known since before the 20th Century began. For the first time, we can now measure that charge in a solution,” said Dasgupta, the Jenkins Garrett Professor of Chemistry and Biochemistry in the UT Arlington College of Science. “This gives you a possibility that didn’t exist before. It gives you new information that couldn’t be accessed before.”

The components that make up organic and inorganic compounds carry differing levels of charged ions. Phosphate, for example, is triple-charged, while chloride is singly charged.  The new charge detector uses a membrane-based separation or desalting technology that detects ions in proportion to their charge and concentration. Because a single standard can be used to determine known and unknown compounds, frequent recalibration of the machine is not needed and efficiency is increased.

The patented method has been incorporated in the new Thermo Scientific Dionex QD, a product Thermo Fisher Scientific debuted in March. The machine combines charge detection with conductivity detection, the traditional method for measuring ions, to greatly improve performance.

 “We are particularly proud of the fact that Dr. Dasgupta’s innovation has made its way into the marketplace,” said Carolyn Cason, vice president for research at UT Arlington. “One of the hallmarks of a vibrant research university is the ability to team with industry to advance scientific application, and that is what Dr. Dasgupta has done.”

An announcement from Thermo Fisher Scientific said the new machine surpasses past products in large part because of its sensitivity to weakly dissociated ions, which are present in numerous organic acids. It said the invention is “well-suited for analysis of phosphates in environmental testing laboratories, organic acids in the food and beverage industry and ethanolamines in the chemical industry.”

“It’s been more than 35 years since we’ve been using conductivity detection and now we have a new mode of detection available for ions and a superior mode of detection,” Srinivasan said during an interview at the PittCon Conference & Expo in March.

Dasgupta has received numerous national and international awards for his work in ion chromatography, including the prestigious 2012 Dal Nogare Award, given by the Chromatography Forum of the Delaware Valley, and the 2011 American Chemical Society Award in Chromatography. He has been awarded more than $18 million in research grants and is the author of more than 400 scientific papers. The latest patent is his 23rd.

Dasgupta’s work is representative of the innovation under way at UT Arlington, a comprehensive research institution of more than 33,200 students and more than 2,200 faculty members in the heart of North Texas. Visit to learn more.

More information about the Thermo Scientific Dionex QD is available at



The University of Texas at Arlington is an Equal Opportunity and Affirmative Action employer.