PHYSICAL AND ENTERIC PROPERTIES OF SOFT GELATIN CAPSULES COATED WITH EUDRAGIT(R)-L-30-D-55

The enteric coating of soft gelatin capsules (SGC) containing ibuprofe n in either PEG 400 or Miglyol(R) was investigated. The effects of two plasticizers, triethyl citrate (TEC) and tributyl citrate (TBC), on t he physical and enteric properties of SGC coated with Eudragit(R) L 30 D-55 were studied. The water soluble plasticizer TEC was found to be a good plasticizing agent for the Eudragit(R) L 30 D-55 irrespective o f the fill liquid, while the TBC provided satisfactory results only fo r capsules containing the hydrophobic fill liquid, Miglyol(R). The com bination of TEC and TBC provided effective plasticization for the acry lic coating regardless of the fill liquid. A subcoat of HPMC showed no effect on the enteric protection of either Miglyol(R)- and PEG-contai ning capsules that were stored at room temperature and zero percent re lative humidity. The moisture content of the gelatin shell of the film coated SGC stored at room temperature and at 0 or 96% relative humidi ty was followed as a function of time. The load strength of the capsul es was measured during 3 months of storage using an Instron universal testing apparatus, and the physical-mechanical properties of the capsu les were correlated with the moisture content of the SGC. As the moist ure content of the gelatin decreased, all formulations exhibited an in crease in load strength.