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In this paper, the capsule material , chitosan and lignin sulfonate abamectin capsule core complex coacervation (complex coacervation) prepared microcapsules . First , the use of orthogonal experimental design on complex coacervation system formation conditions of the initial screening , based on in-depth study of the various factors that affect drug loading and encapsulation efficiency of microcapsules receive appropriate preparation conditions , namely chitosan sugar viscosity of 1500cps, chitosan concentration of 0.5% , a concentration of 2 % sodium lignin sulfonate , the emulsifier Tween80/Span80 ratio is 2:1 , the amount of emulsifier is 6mL , shell core ratio of 6 , the reaction temperature was 45 ℃, into the capsular pH of 5.1, stirring speed 300r/min the complex coacervation 15min , the crosslinker dosage for 4mL crosslinking time of 1h , the resulting microcapsules drug loading and encapsulation efficiency up to 12.6% and 92.1 % . Using a laser particle size analyzer , and scanning electron microscopy were characterized for particle size distribution and morphology of the microcapsules , the results show that : the blank prepared in the average particle diameter of the microcapsules was 5.80μm, and the particle size of the microcapsules of the drug loading in the range of 5 ~ 27μm , The average particle size of 11.2μm, the distribution is more concentrated ; electron micrograph shows : blank microcapsules and drug-loaded microcapsules showed a state of aggregation . FT-IR results show that : the Avermectin with chitosan / lignin sulfonate complex coacervation system chemical bonding between the wall material . Vitro release assay and dissolution experiments of avermectin drug-loaded microcapsules release properties and corrosion of the study results show that : the important factors affecting the release rate of avermectin and AVM- CL microcapsule dissolution rate is shell glycans viscosity (i.e., molecular weight) and the concentration of the solution , into a capsule pH and curing crosslinker . The shell core than the sustained release properties and corrosion performance of the microcapsules law was not significant. The AVM-CL microcapsules prepared under the most optimum conditions of avermectin having a controlled release effect , compared with the original drug of the avermectin , cumulative release of 99 % of the time can be extended from the 6h to 90h . The release kinetics model release curve fitting, the results showed that : segmented treatment
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