resolution of the water-soluble vitamins -- pyridoxin , riboflavin , niacinamide , vitamin b12 , thiamin , ascorbic acid , niacin and folic acid -- by high pressure liquid chromatography was examined on two bonded-phase columns , mubondapak c18 and mubondapak nh2 .
C0028027
niacinamide
C0027996
niacin