Optimization of the formulation of pH-ionic-sensitive in situ gel of Bletilla striata polysaccharide by central composite design-response surface methodology
Objective To optimize the formulation of pH-ionic-sensitive in situ gel of Bletilla striata polysaccharide.Method The contents of deacetylated gellan gum,sodium alginate,calcium chloride,and the ratio of sodium citrate to calcium chloride were chosen as the variables,the preliminary range of each parameter was determined by the single-factor experiments.The viscosity of the precursor solution at 25℃and the gelation viscosity at 37℃were taken as the evaluation indicators,the central composite design response surface methodology was used to optimize the preparation process and carry out the predictive analysis.Results The optimal preparation conditions for the pH-ionic-sensitive in situ gel of Bletilla striata polysaccharide were as follows:deacetylated gellan gum content of 0.50%,sodium alginate content of 1.10%,calcium chloride content of 0.07%,and a ratio of sodium citrate to calcium chloride of 4∶1.Under these prescription conditions,the viscosity of the precursor solution at 25℃was(704.00±3.00)mPa·s,and the gelation viscosity at 37℃was(12 544.70±47.33)mPa·s.Conclusion The pH-ionic-sensitive in situ gel of Bletilla striata polysaccharide has good stability and flowability of precursor solution at 25℃,and the gel has considerable strength,which provides an experimental basis for further research on in situ gel of Bletilla striata polysaccharide.
Central composite design response surface methodologyBletilla striata polysaccharidepH sensitive in situ geldetermination of viscosity