Solution-Phase Techniques for Oligonucleotide Sequencing

The cleavage of nucleic acids in solution with subsequent mass spectrometry detection of the digestion fragments is another possible option for sequencing 

When the Sanger sequencing is performed in conjunction with mass spectrometry, the gel separation and detection of the radiolabeled or photoaffinity-tagged 

DNA and RNA are the two well-known nucleic acids. Structurally, they are oligomers of nucleotides the difference is that the sugar component of DNA is deoxy-D-ribose, and in RNA it is ribose. The DNA bases are adenine, guanine, cytosine, and thymine in RNA, they are adenine, guanine, cytosine, and uracil. 

Several gas-phase fragmentation techniques have found a niche as a possible means to sequence oligonucleotides. These include ESI in-source CID (nozzle-skimmer voltage to induce fragmentation), IRMPD in an FT-ICR MS instrument, MALDI in-source decay and post-source decay, and CID-MS/MS of the ESI-produced ions. CID generates complementary (a — B )- and in-type ions, which can provide bidirectional sequencing from the 5 3 direction and 3 5  

Calculate the monoisotopic molecular mass of the oligonucleotide 5 - f(ACGGATCCG)-3.  

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