Biotinyl-4-aminobenzoic acid (B-PABA) is used as a substrate in biotinidase assays.
Purification Methods
Dissolve the acid in NaHCO3 solution, cool and precipitate it by adding N HCl. Collect the solid, dry it at 100o and recrystallise it from MeOH. Note that it is hydrolysed by aqueous 3M, 1M and 0.2M HCl at 120o