Evaluation of the suspending properties of Adansonia digitata gum on Sulphadimidine Suspension

Adansonia digitata gum was extracted from the dried leaves of Adansonia digitata using hot and cold water extraction processes yielding 16 and 18 % w/w respectively. The suspending properties of the hot (HWE) and cold water (CWE) gum extracts, used at 1-5 % w/w concentration levels were evaluated and compared with Compound Tragacanth (4% w/v) in sulphadimidine suspension. Sedimentation volume and rate, rheology, and ease of redispersion were employed as evaluation parameters. The results showed that both hot and cold water extracts of the gum used at 2-3 % w/v produced a better suspending property than 4 % w/v Compound Tragacanth gum. The suspending ability of the gums was in the order of: CWE > HWE > Compound Tragacanth. When the viscosity of HWE was compared with CWE for 15 days, they were found to differ significantly (P< 0.05). Also, when the viscosity of either hot or cold water gum extracts were compared with that of Compound Tragacanth at the same concentration for 15 days, there was a significant difference (P< 0.05). At all concentrations of gums used, the CWE had the better suspending property. Keywords: Adansonia digitata , suspending agents, rheology, ease of re-dispersibility, sedimentation rate