Study On Properties And Preparation Of Mint Amide Microcapsules

N-ethy-2-isopropyl-5-methylcyclohexane carboxamide is an amide compounds can beused in consumer products, edible products, pharmaceuticals and tobacco products. Besidethese uses, N-ethy-2-isopropyl-5-methylcyclohexane carboxamide also has excellentinsecticide effect. Microcapsules of WS-3are that WS-3is coated by the natural amidepolymers to enhance stability of WS-3. Because of the coating of the wall material, WS-3will be less decompose and loss by the environmental factors （such as rain, light, heat, etc.）and pesticides. Microcapsules can extend the utilization of WS-3, extend its effective time,reduce the number and frequency of pesticide application to improve its environmentalpressure, and can reduce the toxicity of WS-3.The microcapsules of WS-3are made through the single coacervation and thecomplex coacervation. The preparation processing is studied by single factor experiments,orthogonal experiment and response surface analysis. The ideal preparation processing ofthe single coacervation: the ratio of the core material/the wall material was1:2, the wallmaterial concentration was2%, the temperature was45℃, stirring speed was600r/min.The complex coacervation process of the microcapsules of WS-3is studied. The ratio ofgelatin and gum Arabic was1:1, reaction pH value was4.00⁴.20. Preparation processingof WS-3microcapsules by complex coacervation was investigated. Response surfacemethodology was used to optimize microencapsulation including three independentvariables: the wall material Concentration （X₁）, the wall material/core material ratio（X₂）,and the stirring speed（X₃）. A polynomial regression model equation was fitted as follows:Y=29.40+13.9725X₁+7.954X₂+0.3219X₃-0.4875X₁X₂+0.375×10^-5X₁X₃-3.7×10^-3X₂X₃-2.808X₁²-1.015X₂²-2.591X₃². Applying this model equation to thesurface plot and canonical analysis, the optimal conditions obtained for the WS-3Microencapsulation by Complex Coacervation: the ratio of the wall material/the corematerial2.26:1（X₁）, the wall material Concentration2.13%（X₂）, the stirring speed of 605r/min（X₃）.The microcapsules of WS-3by simple coacervation and complexcoacervation are analysised and compared. The properties of the microcapsules are studiedby the Adopted ultraviolet spectrophotometer, optical microscope and electron scanningmicroscope. The shape of the microcapsules is spherical, the appearance is completedensity, liquidity is good, and do not have adhesion. The coated rate of the microcapsule bythe simple coacervation is82.92%, which is less than the coated rate92.06%by thecomplex coacervation. While the drug-loading rate28.15%by simple coacervation is morethan18.7%by the complex coacervation. Judging from an average of particle size, theaverage particle diameter by simple coacervation is15μm, which is smaller than46.3μmby the complex coacervation. According to the environment and requirements, themicrocapsules can be made in different preparation.On the preparation of income of microcapsule on slow-release experiment, inspectsthe different preparation methods, core wall than, release temperature and release mediumpH value other factors on microcapsule cumulative release rate, the effect of proof incomemint amide microcapsules have obvious slow-release role. The release kinetics of themicrocapsules of WS-3was studied. It was shown that the release dates of microcapsulesare fitted with three model equations Higuchi release equation, first order release equation,and zero order release equation. The results of equation fitting show that the release ofmicrocapsules of WS-3is obeyed by first order release equation by comparing correlationcoefficient R. Research similar compounds capsaicin, press the same methodsmicrocapsule optimization, and carries on the slow-release, the results show that therelease of synthetic capsaicin microcapsule is obeyed by first order release equation. Thetransfer model of microcapsules of mint amide is deduced according to the second Ficklaw.