Magic matrices for ionization in mass spectrometry was written by Trimpin, Sarah;Lutomski, Corinne A.;El-Baba, Tarick J.;Woodall, Daniel W.;Foley, Casey D.;Manly, Cory D.;Wang, Beixi;Liu, Chih-Wei;Harless, Bryan M.;Kumar, Ruby;Imperial, Lorelie F.;Inutan, Ellen D.. And the article was included in International Journal of Mass Spectrometry in 2015.Category: nitriles-buliding-blocks This article mentions the following:
The initial discovery that a heated inlet tube of a mass spectrometer is an ionization source producing ions from volatile, nonvolatile, small, and large mols. with charge states similar to electrospray ionization has been advanced to ionization requiring only the vacuum inherent with a mass spectrometer and a suitable matrix. This spontaneous ionization method was first applicable with the matrix 3-nitrobenzonitrile. Here we report that over 40 compounds have now been discovered that spontaneously convert mols. to gas-phase ions when exposed to sub-atm. pressure, some with remarkable sensitivity (10 fmol of protein insulin). The commonality of all matrixes is the ability to sublime, preferably near room temperature, through exposure to vacuum, and the ability to create charge separation under these conditions. The effect of vacuum, airflow, temperature (-80 to +150 °C) and pH (1-9) on the effectiveness of these newly discovered matrixes to ionize peptides and proteins is presented. Compounds with and without acidic hydrogen atoms act as matrixes and ionize specific compound classes. The new matrixes extend applications from peptides, proteins and drugs to compound classes without basic functionality such as lipids and synthetic polymers in the neg. and pos. modes. Mass resolution and ion mobility spectrometry aspects are also discussed. In the experiment, the researchers used many compounds, for example, 5-Methyl-2-nitrobenzonitrile (cas: 64113-86-6Category: nitriles-buliding-blocks).
5-Methyl-2-nitrobenzonitrile (cas: 64113-86-6) belongs to nitriles. The R-C-N bond angle in and nitrile is 180° which give a nitrile functional group a linear shape. Both the carbon and the nitrogen are sp hydridized which leaves them both with two p orbitals which overlap to form the two π bond in the triple bond. Alkyl nitriles are sufficiently acidic to undergo deprotonation of the C-H bond adjacent to the CN group.Strong bases are required, such as lithium diisopropylamide and butyl lithium. The product is referred to as a nitrile anion. Category: nitriles-buliding-blocks
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts