mass spec

-Slang for Mass spectrometry. NOT mass spectroscopy… spectroscopy is NOT the same as spectrometry. Spectroscopy uses light… this spectrometry does not… -A common tool amongst chemists of all varieties since it can distinguish between molecules based on very small differences in mass. In principal it works by ionizing a molecule with some sort of ionization source (electron impact, electrospray ionization, chemical ionization, MALDI, ect…), the charged molecule is then accelerated through a mass selector, which can vary in form from a magnetic sector to a quadrupole, to a time of flight (TOF) selector. After selection, the molecule is directed to a detector where it is measured or directed to another portion of the apparatus for further experimentation. Mass spectrometry has been coupled with many separation methods such as HPLC, GC, and CE to yield quantitative information, while tools such as ICR has been developed for studies of reaction dynamics. Many experiments have been devised to measure very low concentrations of analyte since the sensitivity and signal to noise are so high. Also, the resolution of many spectrometers is quite good, allowing for molecules of similar mass to be distinguished. Organic chemists tend to use it for structure elucidation since a pattern of fragments can be used to piece together the structure when combined with other methods such as NMR and FTIR.