View on hplc.cloud1,5-Naphthalenedisulfonic acid is a strong organic acid with a double charge. Multi-charged molecules generally have a tendency to exhibit poor peak shape in HPLC on reverse-phase columns showing significant tailing. The acid can be retained with great peak shape on a Newcrom BH mixed-mode column. The Newcrom line of columns was designed specifically for improved peak shape of multi-charged molecules. The method uses a mobile phase consisting of acetonitrile (ACN), water and ammonium formate buffer, making the method MS-compatible. UV detection at 260nm can also be used.