PRELIMINARY EVALUATION OF DELONIX REGIA SEED GUM AS A SUSPENDING AGENT IN A LIQUID ORAL DOSAGE FORM

Abstract

The study focused on the extraction and utilization of Delonix regia seed gum as a suspending agent in amoxicillin dry granules for reconstitution. The seeds were dehauled, defatted with diethyl ether and the gum extracted from its aqueous dispersion by antisolvent precipitation method. Delonix regia gum (DRG), sodium carboxymethyl cellulose (CMC) and hydroxylpropylmethyl cellulose at 0.50, 0.75 and 1.00% (with or without NaCl at 0.02% or 0.04%) were separately used to formulate amoxicillin granules. The granules were reconstituted and characterized using standard protocols for suspension dosage forms. Results revealed that at similar concentrations, products viscosities were: CMC>HPMC>DRG; and pourability: DRG>HPMC>CMC. At 1.00%, DRG gave the best product and flocculation with NaCl was better at 0.02%. The order of degree of flocculation at 1.00% suspendant and 0.02% NaCl was DRG>HPMC>CMC, while at 0.04% NaCl, it was CMC>HPMC>DRG. Ease of redispersion for DRG products was significantly better (p<0.05) than those of CMC, HPMC and two popular commercial products in Nigeria. Particles shapes and interaction with the excipients as revealed by photomicrographs illuminated some of the observed properties of the products, in that the ones whose particles were planar or acicular shaped had significantly higher (p<0.05) degree of flocculation than products containing mostly circular particles. In conclusion, the qualities of products formulated with DRG compared very well and for redispersibility is significantly better (p<0.05) than products formulated with standard suspending agents and the two popular commercial products in Nigeria markets.