My research focus is on the development of mass spectrometric techniques and their application to environmental biomonitoring, clinical toxicology, and therapeutic drug monitoring in MDR-TB patients.
In biomonitoring, my laboratory is pioneering the application of high resolution mass spectrometry to the suspect screening of environmental chemicals in biological samples. We have have also continuously developed innovative and sensitive liquid chromatography- mass spectrometry (LC-MS) methods for measuring environmental chemicals (e.g. environmental phenols such as BPA, BPS and triclosan; phthalate metabolites; perfluorinated compounds; pesticides; and, flame retardants) in a variety of biological matrices including serum, urine, amniotic fluid, placenta, hair, and other human and animal tissues.
My laboratory also specializes in the analysis of new psychoactive substances (NPS) using high resolution and tandem mass spectrometry to aid Poison Centers, Medical Examiner’s Offices, and various government agencies including the Drug Enforcement Administration, the Centers for Disease Control and Prevention, and the National Institute of Occupational Safety and Health, in tracking down synthetic drug intoxications and epidemics. In 2016 I established the Pshychoactive Substances Consortium and Analysis Network (PSCAN), a consortium of ten medical centers prospectively collecting cases that may have NPS etiology to pair comprehensive clinical data with NPS analysis data in their corresponding biological samples with the aim of potentially defining toxidromes specific to various NPS classes. This year my laboratory has been awarded by a Department of Justice (DOJ)- DEA research contract to conduct the national surveillance on NPS intoxications and mass outbreak.
More recently, I have also started working with the Positive Health Program at San Francisco General Hospital to develop LC-MS methods for hair TB drug monitoring in HIV/AIDS patients and related studies. We have successfully developed an LC-MS/MS panel to simultaneously measure 11 TB drugs in hair including new drug-resistant TB medications. The panel is currently being used for drug adherence monitoring among multi-drug resistant TB patients.