Engineering Spherical Beads as an Approach to Improve the Physico-Mechanical Properties of Poorly Soluble Drugs

Improving oral bioavailability of drugs given as solid dosage forms remains a challenge for the formulation scientists due to solubility problems. To address this encumbrance, ionotropic gelation technique has attracted considerable interest of improving the dissolution rate of highly lipophilic drugs thereby improving their bioavailability by engineering spherical agglomerates. Spherical beads of poorly water soluble drug, piroxicam, were formulated by dispersing the drug in solutions of ionic polysaccharide sodium alginate and then dropping these dispersions into a solution of the counterion calcium chloride. The droplets rapidly created gelled spheres by ionotropic gelation. Strong spherical beads could be engineered with high yield and a drug content approaching 100%. The flow characteristics of micronized rods like crystals were significantly enhanced by this agglomeration technique when compared to the non-agglomerated drug crystals. Furthermore, scanning electron microscopy, size, image analysis, dissolution profiles and compression properties of piroxicam beads were evaluated. Beads engineered by using 1% sodium alginate and 3% calcium chloride gave the most desirable results as compared to other compositions.