Poster abstracts
Poster number 106 submitted by Robert Ross
Inductive Based Fluidics mass spectrometry for the analysis of modified nucleosides in RNAs
Robert Ross (Department of Chemistry, University of Cincinnati), Drew Sauter (nanoLiter, LLC, Henderson, NV ), Patrick A. Limbach (Department of Chemistry, University of Cincinnati)
Abstract:
Post-transcriptional chemical covalent modification of adenosine, guanosine, uridine and cytidine occurs frequently in all types of ribonucleic acids (RNAs). In ribosomal RNA (rRNA) and transfer RNA (tRNA) these modifications make important contributions to RNA structure and stability and to the accuracy and efficiency of protein translation. These modifications can be present at very low levels and their analysis can be challenging. Thus, newer analytical methods capable of higher sensitivity analysis of modified RNAs would be advantageous. Inductive Based Fluidics (IBF) as a means for RNA sample introduction could be a way to increase sensitivity. Inductive Based Fluidics (IBF) uses inductive charging to produce nanoliter-sized droplets. Here we have compared IBF with nano electrospray ionization (nESI) and micro-ESI for the LC-MS/MS analysis of enzymatically digested RNA. At flow rates < 2 μL/min, the analyte signal to noise with IBF was found to be comparable or higher to nESI. The analyte S/N for IBF was found to decrease below that obtained from ESI-based sources at higher flow rates, likely due to limited desolvation. The analytical advantages of IBF include ease of use and an improved ability to handle “salty” oligonucleotide samples without capillary plugging. Further, preliminary results suggest improved detection of modified nucleosides of low proton affinity, such as modified uridines, for IBF over nESI.
Keywords: Inductive Based Fluidics, nucleosides, modification