Structural characterization and dissolution profile of mycophenolic acid cocrystals
Three novel cocrystals of mycophenolic acid (MPA) with isonicotinamide (MPA-ISO), minoxidil (MPA-MIN) and 2,2′-dipyridylamine (MPA-DPA) as coformers have been prepared successfully by both slow evaporation and liquid-assisted grinding. The structures of these cocrystals show that all the three coformers form hydrogen bonds with the carboxylic acid group of MPA. The cocrystal MPA-ISO possesses remarkably improved solubility and dissolution rate, while two other cocrystals exhibit the opposite characteristics. The solids in the slurry with pH 6.8 phosphate buffer and cocrystals remain as the incipient cocrystal after 24 h. However, evidence of slight polymerization was shown in the slurry of pH 6.8 phosphate buffer with MPA and MPA-ISO cocrystal.Graphical Abstract
The cocrystal of MPA with ISO, DPA, or MIN has either higher or lower dissolution profile than that of pure MPA.