Optimization of the O-carboxymethyl chitosan hemostatic sponge by the central composite design-response surface methodology

OBJECTIVE To optimize the formulation of O-carboxymethyl chitosan hemostatic sponge and to prepare the o-carboxymethyl chitosan hemostatic sponge. METHODS The rabbit ear vessels,bleeding wound model was established. O-carboxymethyl chitosan,glutaraldehyde and CaCl2were selected as carrier,coagulant and hemostatic promoter,respectively. The hemostatic time and bleeding volume( weight) were selected as optimized indexes. The central composite design-response surface methodology was used to screen the optimized prescription. The freeze drying technology was used to prepare the O-carboxymethyl chitosan hemostatic sponge,and its hemostatic effects were verified. RESULTS The optimized formulation of o-carboxymethyl chitosan hemostatic sponge was as follows: O-carboxymethyl chitosan 2. 49%,glutaraldehyde 1. 08% and CaCl22. 11%,respectively. The ratio of O-carboxymethyl chitosan,glutaraldehyde and CaCl2was 10 ∶ 0. 1 ∶ 5. The gained sponges had porosity and good tenacity. Both the hemostatic time and bleeding volume( weight) in the rabbit ear vessels,bleeding wound model were( 53. 0 ± 8. 5) s and( 0. 151 ± 0. 020) g,respectively.The hemostatic efficacy conformed to the predicted value. CONCLUSION The optimized prescription with central composite designresponse surface methodology was reasonable and the prepared O-carboxymethyl chitosan hemostatic sponge has the significant hemostatic efficacy.