Our R&D activity encompasses development of methodologies for sensitive trace detection, identification and reliable quantitation of therapeutic drugs and their related metabolites in body fluids and tissues, allowing for broadening of their diagnostic time window. We establish highly sensitive mass spectrometry (MS) assays, a comprehensive approach to Tox-Screen in body fluids and drugs pharmacokinetics in clinical trials involving high throughput applications.
Retrospective detection of CWA intoxication
A new method was developed for retrospective determination of Sarin in human whole blood and plasma samples. This method, based on fluoride reactivation process for G-analog generation, is useful for detection of ultra-trace levels of OP (Organo Phosphorus) agents in blood, long after the actual exposure. Its sensitivity suggests that such analysis could also be applied in cases where no adverse symptoms were observed.
Fluoride reactivation process for G-analog generation
Detection of sulfur mustard intoxication
Sulfur mustard (HD) is a chemical warfare agent known as a powerful vesicant and potent biological alkylating agent. The metabolism of HD has been studied and several urinary metabolites were identified and reported. HD reacts with two molecules of glutathione and oxidize to sulfone followed by β-lyase cleavage leading to 1,1- sulphonylbis-[2-(methylthio)ethane] (SBMTE), which further oxidizes to 1-methylsulphinyl-2-[2- (methylthio) ethylsulphonyl]ethane (MSMTESE) and 1,1-sulphonylbis[2-(methylsulphinyl)ethane] (SBMSE) known as β-lyase metabolites. MSMTESE and SBMSE are considered to be specific markers for HD exposure, they form in relatively high concentrations and persist in urine for several days. SBMTE was not identified in animal urine, but is known to be a precursor for β-lyase metabolites in human urine. The biological fate of HD has been studied in rats and pigs. Several time-consuming and laborious analytical methods have been reported for measuring HD metabolites in urine. We present a simple method which combines a short cleanup step followed by LC-MS-MS (MRM) analysis for the determination of β-lyase metabolites.
Kinetic profile of b-lyase SBMSE metabolite (pigs exposed to HD by cutaneous application)
Toxins
Rapid Botulism diagnosis by a newly-developed Mass-Spectrometry assay, an infant intoxication case. A successful collaboration between the Analytical Chemistry and Biotechnology departments at IIBR led to the development of a rapid, selective and sensitive
in vitro assay, based on endopeptidase-mass-spectrometry, for the detection of botulinum toxins (BoNTs). BoNTs are produced by
Clostridium botulinum bacteria and are considered to be the most poisonous substance. Therefore, a highly-sensitive method that would allow their early detection and relevant treatment is essential. The newly developed assay enables diagnosis of botulinum within a few hours and replaces the standard
in vivo mouse bioassay that requires a large number of mice and more than 96 hours to complete. Using our endopeptidase-mass-spectrometry assay, the botulinum toxin was detected in an infant’s serum within the intervention-relevant time, whereas all conventional tests provided negative results.
This work was widely published in both clinical and basic-biochemistry journals.