Applications of mass spectrometry to oligonucleotides

The simplest and also most common application of mass spectrometry is the accurate determination of molecular weight to verify the presence of an oligonucleotide of a 

The MALDI/TOF mass spectrum of an oligonucleotide that has undergone a partial depurination reaction. Reproduced (modified) from Van Ausdall D.V. and Marshall W.S., Anal. Biochem., 256, 220-228, 1998, with permission. 

An important advantage of mass spectrometry over other techniques such as electrophoresis or chromatography is its high speed. For instance, the association of MALDI/TOF with automatic preparation of the samples, together with automated acquisition of the spectra, allows the analysis of more than 100 oligonucleotides in 90 min. [172] 

Determination of the size or molecular weight of nucleic acids is crucial in molecular biology. This importance is increased by the introduction of the PCR, which allows an individual to be identified (e.g. a pathogen bacteria) or the genetic links between individuals and allows the prediction or diagnosis of diseases. 

The MALDI/TOF mass spectrum of an oligonucleotide produced by PCR amplification of a part of the gene responsible for cystic fibrosis. The top spectrum is obtained from a normal individual, whereas the central and bottom spectra are obtained, respectively, from a healthy heterozygote carrier and an ill homozygote. Reproduced (modified) from Chang L., Tang K., Shell M., Ringelberg C., Matteson K.J., Allman S.L. and Chen C.H., Rapid Comm. Mass Spectrom., 9, 772, 1995, with permission. 

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