Division of Residue Chemistry

Biography

Dr. De Alwis is a research chemist and a principal investigator with the Division of Residue Chemistry in the Office of Research at FDA’s Center for Veterinary Medicine (CVM). She received her BSc degree from the University of Colombo, Sri Lanka, and her PhD from Flinders University, South Australia. She joined FDA in October 2006. Her primary responsibilities at CVM include conducting and coordinating research on the development and evaluation of analytical methods for drug residues and environmental contaminants in animal tissues, fluids, and feeds.

Research

• Analytical method development for drug residues and toxic environmental contaminants
• Comparison of urinary chemical profiles between healthy and diseased dogs to identify chemicals causing adverse health outcomes
• Targeted analysis: LC-MS/MS (liquid chromatography/tandem mass spectrometry)
• Non-targeted analysis: LC-high resolution accurate mass spectrometry

Select Publications

Duelge, Kaleb J., Upul Nishshanka, Hemakanthi G. De Alwis. “An LC-MS/MS method for the determination of antibiotic residues in distillers grains at levels of concern for antimicrobial resistance development.” J. Chrom. B, vol 1053, 81–86, 2017

Nishshanka, Upul, Hiranthi Jayasuriya, Chaitali Chattopadhaya, Philip J. Kijak, Pak-Sin Chu, Renate Reimschuessel, Andriy Tkachenko, Olgica Ceric, and Hemakanthi G. De Alwis. “Screening for toxic phorbol esters in jerky pet treat products using LC-MS.” J. Chrom. B, vol 1020, 90–95, 2016

De Alwis, H. G., Kijak, P.J., Rummel, N., Girard, L. “Determination of erythromycin in medicated salmonid fish feed by liquid chromatography and UV spectroscopy.” J. AOAC Int., vol 96, 1233–1238, 2013

De Alwis, H., Heller, D.N. “Multiclass, multiresidue method for the determination of antibiotic residues in distillers grains by liquid chromatography and ion trap tandem mass spectrometry.” J. Chrom. A, vol 1217, 3076–3084, 2010