طيف سنجي جرمي ليزري آمينواسيد ها و محاسبه طيف فوتوالكترون مولكول هاي زيستي

چكيده انگليسي :

Laser Mass Spectrometry of Amino acids and Calculation of Photoelectron Spectra of Biomolecules Fatemeh Abyar E mail f abyarfirouzabady@ch iut ac ir Date of Submission April 2015 Department of Chemistry Isfahan University of Technology 84156 83111 Isfahan Iran 1st Supervisor Mahmoud Tabrizchi E mail m tabriz@cc iut ac ir 2nd Supervisor Hossein Farrokhpour E mail farrokhphossein@gmail com Advisor Mahdi Kadivar E mail kadivar@cc iut ac ir Department Graduate Coordinator Alireza Najafi Department of Chemistry Isfahan University of Technology Isfahan 84156 83111 Iran fax 983133912350 Department of Food Science and Technology Isfahan University of Technology Isfahan 84156 83111 Iran Abstract In this work linear laser ionization TOF mass spectrometer has been constructed and successfully tested The experimental section of the investigation is laser mass spectrometry of amino acids with three methods including MALDI ion attachment and Indirect Laser Desorption Ionization ILDI were considered The Matrix Assisted Laser Desorption Ionization MALDI mass spectrometry method was started up in Iran for the first time The results of this section includes the recorded MALDI spectra of the amino acids which the ionic fragmente MH is observable in the spectra Experimental conditions were optimized for the MALDI technique In the other part ion attachment method were performed for mass spectrometry of amino acids In this method Cations of samples are created from alkali salts by laser radiation directly on the sample so that the metal cations are attached the sample molecules Also the new method introduced in laser laboratory of chemistry department of Isfahan University of Technology IUT In this method laser light IR radiation is irradiated on the backside of plate which sample is coated we recorded species AA M AA H 2M in the mass spectra for amino acids In computational section The electronic structures and photoelectron spectra of biological molecules including unsaturated saturated steroids and fat soluble vitamins were calculated theoretically in this work The calculated photoelectron spectrum of each compound was compared with its corresponding experimental spectrum reported in literature The calculations were performed using symmetry adapted cluster configuration interaction SAC CI with two code SAC CI SD R and Direct SAC CI SD R using different basis set The molecular orbitals involved in the ionization of each compound were calculated at the HF level of theory The spectral bands of each compound were assigned by natural bonding orbital NBO calculations Keywords Time of flight Laser Ionization Alkali Halides Steroids Photoelectron Spectroscopy SAC CI NBO 1 Introduction Time of flight TOF mass spectrometry MS is one of the most important methods for quantitative and qualitative analysis of materials The ionization source in TOF mass spectrometry can be electron impact radioactive laser synchrotron radiation MALDI Electrospray Ionization ESI Matrix assisted laser desorption electrospray ionization MALDESI and Electrospray assisted Laser Desorption Ionization Mass Spectrometry

آبيار، فاطمه

طيف سنجي جرمي ليزري آمينواسيد ها و محاسبه طيف فوتوالكترون مولكول هاي زيستي

MALDI , يونش ليزري , استروئيد , ويتامين , SAC-CI