strong acid

 Step 5

We have established that your compound is a hydrophilic strong acid with one acidic group. Below is an example of a separation of a similar compound. This example can be used a starting condition in your method development.

Hydrophilic strong acid compounds have no or very low interaction with the stationary phase by reverse phase mechanism. The negative charge of the molecule can be used as a means of retention in ion-exchange mode. Strong organic acids with pKa 2.5 and below can not be completely deionised by lowering pH of the mobile phase. For this reason the pH of the mobile phase has no or little effect on separation. The concentration of buffer or ion-strength of the mobile phase is a key factor that effects the retention of this type of analyte. Such anion-exchange reverse phase columns as Primesep D, B2 and special column Primesep AB (the column for both cation and anion-exchange separation) are most suitable in this case.