If you're new to oligos I'll inspire you with confidence
I'll give you a primer just for the compliments
Analysis of ASOs make it make sense
LC for oligos different approaches taken
If it's your first day with oligo reverse phase
Doing so without ion pair is the worst way
Oligos are polar I know you're thinking HILIC
Separation is not optimal if you can believe it
Selectivity is limited and not so decent
Ion pair definitely is what you should lead with
ASOs having so many impurities
Shortmer N-1 five prime first to leave
CNET ADP impurities assuredly
Difficult chromatographic separation perfectly
Meaning separation of oxidized thioate baseline
Might not be feasible and you don't wanna waste time
For resolution improvement no Triethylamine
DMCHA it's better to me
It's the change in pH and hydrophobicity
Increases the selectivity and ESI efficiency
Don't trip if you start to see the peaks broaden
Sulfurization thioester that causes
R and S isomers shallow gradients resolve them
Would ion mobility help solve the problem
Depending on the oligo GC content
Chromatographic run needs to be at hot temp
No ACN use Methanol as the strong solvent
And now you're resolving impurities with the column
Ion pair makes the mobile phase more basic
The acidic modifier most often used HFIP
HFIP improves ESI sensitivity
Low boiling point helps solvation efficiency
But hexafluoroisopropanol you see that
Perfluorinated alcohol ain't that a PFAS
I can't believe forever chemical should cease that
But I need to analyze my siRNA I need that