A new preparation method of the sustained-releasing microspheres containing acetamiprid was developed with carboxymethyl chitosan and acacia as base materials.The preparation condition were optimized using L16(45) orthogonal experimental design with the drug encapsulation and the shape of the microspheres as criteria.As a result,the optimum preparation conditions of the microspheres were as follows:the concentration ratio of carboxymethyl chitosan to acacia was 1∶3,the dosage of acetamiprid was 1.0 g,the amount of 10 % glutaraldehyde was 16mL.The complex coacervation reation was conducted at 45 ℃ for 80min.The experimental results showed that there were no chemical interactions between acetamiprid and the carboxymethyl chitosan/acacia complex and a good drug releasing performances of the acetamiprid microspheres was obtained.
