Georgia Tech Researchers Develop Anticounterfeiting Analytical Chemistry Techniques

A group of researchers from Georgia Institute of Technology (GeorgiaTech, Atlanta, GA, www.gatech.edu)is using high-throughput ionization techniques to identify and measurethe ingredients in counterfeit drugs.

The team initially began its project using standard analyticaltechniques such as liquid chromatography and mass spectrometry, butfound these methods to be too slow (more than two hours for one sample)for implementation in the drug supply chain. To accelerate analysistime, Assistant Chemistry and Biochemistry Professor Facundo Fernandezand his graduate students developed techniques that ionize the surfaceof a solid sample under atmospheric pressure. Then, researchers usemass spectrometry to analyze the particles, which reduces samplepreparation time. According to the group, its high-throughputionization techniques enable analytical analyses in five seconds persample.

"This is a new generation of techniques in mass spectrometry,"Fernandez said in a news release from the university.

Two recently developed analytical chemistry techniques are at the heartof the group's research: desorption electrospray ionization (DESI) anddirect analysis in real time (DART). DESI, a technique created atPurdue University, uses a charged alcohol-water spray to collectmolecules from a sample's surface and transfer them to a detector. Forunstable molecules, the researchers use "reactive DESI," in which theyadd an alkylamine to the mixture to prevent fragmentation.

DART is an ion source developed by Jeol Ltd. (Tokyo, Japan,www.jeol.com) for noncontact sample analysis. Fernandez's team plans tointerface DART with an ion-mobility spectrometer in the future to helpscreen solid samples of antimalarial drugs in the field.

Said Fernandez, "We foresee that both DART and DESI will have atremendous impact in a variety of scientific fields, ranging from drugquality control, screening and discovery to biological applications,such as metabonomics and/or proteomics."

The group will publish a report on their research in the journal ChemMedChem later this summer.