Study of abietic acid glycerol derivatives as microencapsulating materials.

Abietic acid (85 per cent pure) was extracted from rosin N Grade and further standardized. Abietic acid derivatives were prepared by heating abietic acid with glycerol and intermediate reaction products with different acid values were collected. Salicylic acid granules were encapsulated using a 10 per cent solution of abietic acid and its derivatives by standard spray pan technique. The coated microcapsules were evaluated for moisture absorption, dissolution and flow properties. The result showed that abietic acid glycerol derivatives, AaG-54 and AaG-20 had better moisture protection properties. Dissolution studies indicate that these derivatives could be used for delayed release of drugs.