A Concise Review on Time of Flight (TOF) Mass Spectrum

Abstract

Time of Flight Mass Spectrum is a method of mass spectrometer depending on the time which has been taking to reach the detector (usually located between 1 to 2 min from the source to separate ions) where the Sample is taken and mixed with matrix {the matrix is made up by chemical compound (2,4 Benzoic acid and cinamic acid) and they act as chemical cross link to produce matrix}. The energy source of this procedure is laser. Never the less, the ratio between sample and the matrix is 1:10,000 in order to prevent hampering the. However, TOF has some advantages such as unlimited upper ( mass /charge ) values to be detect, high resolution, good definition of narrow chromatographic peaks , good sensitivity and high quality spectra, High accurate mass measurement to the nearest 0.1 millimass unit for determining the elemental composition for ions less than 500 Da and It can perform tandem MS. Never the less, it has some drawbacks as requiring higher vacuum, Resolution changes with m/z value and high cost equipment. We conclude from this paper that: TOF is considered as one of the best mass filters because of unlimited upper (mass / charge) values to be detected as well as the capability of acquiring rapidly for averaging and good definition of narrow chromatographic peaks.