#11 Pai-Shan Chen

Thermosensitive nanovesicle for direct trap and release of drugs couple to LC-PDA and nano LC-MS

Pai-Shan Chen

Graduate Institute of Toxicology, National Taiwan University, Taipei, Taiwan

paishanchen@ntu.edu.tw

Abstract

A thermosensitive nanovesicle-cloud point microextraction technique has been developed for the determination of drugs with a broad range of polarity in field water and human urine. Liquid-liquid extraction (LLE) is generally applied for this purpose, but it requires large volumes of organic solvents and multiple extraction steps. The analytes of interest generally come with a lot of interferences in extraction phase. The current trends in environmental technology focus on simplifying extraction procedures with low technical demands. The single-drop microextraction method and liquid-phase microextraction techniques have been proposed by them a solvent-minimized sample pretreatment in which a few-μL droplet of organic solvent is immersed in an aqueous solution to extract analytes. Although these inspiring methods have been developed to extraction analytes in field waters, there is no suitable one to extract both polar and nonpolar substances at the same time. Based on thin-film hydration, the conformation of nanovesicles formed by a binary mixing system with the nonionic surfactants was evaluated using regular and cryogenic transmission electron microscopy. The multilayered nano-spherical structure was able to capture polar and nonpolar compounds simultaneously. Analgesic drugs were detected by ultra-performance liquid chromatography (LC) coupled to photodiode array detection and further to nano LC-mass spectrometry. Under optimal conditions, linear calibration curves were obtained over the range of 50 to 8000 μg L-1. The coefficient of determination (R2) ranged from 0.9953 to 0.9995, with detection limits of 10 to 100 μg L-1. The relative recoveries obtained from one industrial wastewater sample and two field water samples ranged from 86.1% to 108.1%. In the human urine analysis, three volunteers ingested 1500 mg of acetaminophen. After 4 hours, the concentration of acetaminophen in the urine was found to range from 87.0 to 197.9 mg L-1.

Short Bio

Dr Chen was an Associate Professor in Department and Graduate Institute of Forensic Medicine, National Taiwan University. She received the B.S. in Chemistry, National Taiwan Normal University., Taiwan, M.S. in Chemistry, National Tsing Hua University, Taiwan, and the Ph.D. in Environmental Sciences and Department of Forensic and Analytical Science, King’s College London, U.K. Dr. Chen’s research interests have involved in forensic toxicology and method development. Current research work in her laboratory are relative to three aspects: (1) developing liquid phase microextraction techniques to concentrate organic compounds including pesticides, drugs or environmental toxins in food, biological and environmental samples; (2) investigating metabolism of drugs of abuse in forensic medicine; and (3) studying differential mobility spectrometry-tandem mass spectrometry to analyze chemically similar drugs in gas phase. She has been focusing on analytical toxicology since her PhD. She is the editor in chief of the Taiwan Journal of Forensic Medicine (Taiwan) (2012-till now); She is the Supervisor (2012-2016) and Secretary General of Taiwan Society of Forensic Medicine (2016-till now).