Mollie A. Glenister, Thomas C. Minshull, Robert L. Ross, Ken Cook, Joshua D. Hinkle, Mark J. Dickman. “Ion-pair reversed-phase liquid chromatography-mass spectrometry analysis of oligonucleotide therapeutics using fluoroalcohol-free mobile phases.” ChemRxiv (). https://doi.org/10.26434/chemrxiv.15007460/v1

OGN1 (Tofersen) impurity profile
OGN1 (Tofersen) Monoisotopic mass 7123.156 Da; mass difference to FLP 0 Da; observed mass 7123.152 Da; mass error −0.5615 ppm; average fractional abundance DBA/HFIP 45.86 %, DBA/IPA 83.19 %, DBA/2,4-DMP 86.72 %
PS/PO Monoisotopic mass 7107.156 Da; mass difference to FLP −16 Da; observed mass 7107.174 Da; mass error 2.533 ppm; average fractional abundance DBA/HFIP 1.6937 %, DBA/IPA 1.5841 %, DBA/2,4-DMP 1.3752 %
Baseloss A Monoisotopic mass 6988.156 Da; mass difference to FLP −135 Da; observed mass 6988.100 Da; mass error −8.014 ppm; average fractional abundance DBA/HFIP 0.2794 %, DBA/IPA 2.3780 %, DBA/2,4-DMP 3.1749 %
Baseloss T Monoisotopic mass 6997.156 Da; mass difference to FLP −126 Da; observed mass 6997.110 Da; mass error −6.574 ppm; average fractional abundance DBA/HFIP 0.0170 %, DBA/IPA 0.4458 %, DBA/2,4-DMP 0.4804 %
Baseloss G Monoisotopic mass 6971.156 Da; mass difference to FLP −152 Da; observed mass 6971.080 Da; mass error −10.902 ppm; average fractional abundance DBA/HFIP 0.0213 %, DBA/IPA 0.0507 %, DBA/2,4-DMP 0.0539 %
Truncation 5' 8-20 Monoisotopic mass 4564.647 Da; mass difference to FLP −2832 Da; observed mass 4564.646 Da; mass error −0.219 ppm; average fractional abundance DBA/HFIP 0.7545 %, DBA/IPA 1.0653 %, DBA/2,4-DMP 0.7538 %
Truncation 5' 6-19 Monoisotopic mass 4919.679 Da; mass difference to FLP −2204 Da; observed mass 4919.667 Da; mass error −2-439 ppm; average fractional abundance DBA/HFIP 0.7400 %, DBA/IPA 1.0206 %, DBA/2,4-DMP 0.7609 %
LC-MS followed by mass deconvolution, deamination unable to detect any deamination under the conditions used