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 Applied Science 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-related matrices.

Research

• Analytical method development for drug residues and environmental contaminants in animal tissues, fluids and feeds using liquid chromatography/tandem mass spectrometry (LC-MS/MS) and LC/high-resolution MS
• Laboratory evaluation of analytical methods in support of new animal drug approval 

Select Publications

Hemakanthi G. De Alwis, Cristina Nochetto, LC-MS/MS Determination of Antibiotic Residues in Distillers Grains: Method Modification, Journal of AOAC International, 106(3), 2023, 517-522

Hemakanthi G. De Alwis, Philip J. Kijak, Cristina Nochetto, An LC-MS/MS Method for the Determination of Antibiotic Residues in Distillers Grains: Collaborative Study, Journal of AOAC international, Volume 104, Issue 5, 2021, Pages 1213–1222

Hemakanthi G. De Alwis, Kaleb J. Duelge, Cristina Nochetto, Upul Nishshanka, Philip J. Kijak, An LC‐MS/MS Method for the Determination of Antibiotic Residues in Distillers Grains, FDA Foods Program Compendium of Analytical Laboratory Methods: Chemical Analytical Manual, September 2020, Method number C-012.01

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