Tatsuya Urabe has completed his PhD in 2010 from Tokyo University of Marine Science and Technology and worked as a postdoctoral researcher of Japan Society for the Promotion of Science (JSPS) until 2011. Now he is working in an accelerator facility at RIKEN and developing a new mass spectrometer based on accelerator science.
We have been developing a mass spectrometer based on plasma ion source, ECRIS (Electron Cyclotron Resonance Ion Source). Although ECRIS is known as a large-sized ion source in accelerator facility, we succeeded to miniaturize and mount it on a portable mass spectrometer (called “miniECRIS-MS”) for detecting gas compounds1). The miniECRIS-MS contains a permanent magnet for an ion source, ion optical system, quadrupole mass analyzer and so on. In this poster session, we will present our ongoing project for quantifying elements in liquid samples. Comparing gas samples, liquid sample introduction into high vacuum plasma (i.e. ECRIS) is troublesome. However, it can offer great advantages over present analytical methods such as ICP-MS in terms of stability, sensitivity, freedam from polyatomic (spectral) interence, initial/running costs, and portability. Details of sample introduction system are as follows. Electrospray is used as a splaying unit of liquid samples at first stage.The solutions containing the analyte of interest are electrosprayed and gradually desolvated with the aid of heated assist gas at atmospheric pressure. Then, sample aerosol was introduced into ECRIS through differential pumping systems. Since analytes of interest are charged by electrospray (as relatively large clusters), they can be electrically extracted by ion lenses such as ion funnel in the pumping system. And they are finally reached at ECRIS and ionized (decomposed) into monvalent atomic ions for quantitative purpose. By this system some solvents (water and methanol) and inorganic elements (Na) were successfully observed, and the potential of miniECRIS-MS will be discussed in the session.
I have completed my PhD at the age of 28 years from Ganpat University, Gujarat, India. I am assistant professor in Quality Assurance Department, Shree S. K. Patel College of Pharmaceutical Education and Research, Ganpat University, Gujarat, India since last 10 years. I have published more than 37 papers in reputed national and international journals.
In this study, an attempt was made to describe and validate a liquid chromatography coupled with tandem mass spectrometry method for the quantification of methoxsalen, an antipsoriatic agent in human EDTA K3 plasma according to the current bioanalytical guidelines. The internal standard used was methoxsalen D3. The separation was performed on a Symmetry, C18, 4.6X 150 mm, 5 µm column using a mobile phase of 2 mM ammonium acetate and methanol 15:85 (v/v) with a flow rate of 0.80 ml/min. The detection of methoxsalen and the internal standard was performed in multiple reactions monitoring (MRM) mode using LC/MS/MS Mass Spectrometer with electro spray ionization, operating in positive ion mode. The human plasma samples were extracted using liquid-liquid extraction with methyl tert-butyl ether. The method shows a good linearity (R2 > 0.98), precision and accuracy over the range of 0.1-100 ng/ml methoxsalen in plasma. The recovery was between 93.85 and 105.25%. The limit of quantification was 0.1 ng/ml. The analysis required about 3.2 minutes run with retention time of drug 2.2 minutes. The proposed method was selective, sensitive, accurate and precise enough to be successfully applied to bioequivalence study.