Preparation Of Cycloxaprid/?-Cyclodextrin Inclusion Complex And Its Preparation

Cycloxaprid(CYC)is the first new nicotine pesticide,which shows antagonistic property to acetylcholine receptor.With the special mechanism and the high insecticidal activity,CYC could be a promising pesticide in agriculture.However the insolubility and unstability of CYC in water had limited its development.Therefore,the inclusion complexes of CYC and(3-cyclodextrin((3-CD)were prepared.Both dual wavelength spectrophotometric analysis method and preparation method of CYC/?-CD inclusion complex were found.The preparation of CYC/?-CD inclusion complex was optimized by single-factor method,and the results were as follows:the ratio of CYC and?-CD was 1:2;the content of ethanol was 30%;the volume of solution was 300 mL;the pH value was 8.5;the temperature of reaction was 40?;the reaction time was 4 h and the stirring rate was 150 r/min.The CYC/?-CD inclusion complex was characterized by means of scanning electron microscope(SEM),X-ray diffractometry infrared(XRD)and infrared spectroscopy(IR).The solubility of CYC/(3-CD increased to 7.56 mg/mL and its stability was also improved.The formulation of CYC wettable powder.was optimized by carriers screening,additives screening and mixture design.Extreme vertex design was used to determine the optimal mixture proportion of silica white,kaolinite and additives 2020.It was proved that the suitable contents of silica white,kaolinite and adjuvant 2020 in 25%CYC WP were 0.8921,0.0297 and 0.0782,respectively.Under these conditions,predicted wetting time,suspensibility and pH value of 25%CYC WP were 40 s,71.19%,6.78,respectively.Furthermore,the experimental results were in good agreement with those predicted.As same as the optimal experimental of 25%CYC WP,the formulation of CYC/?-CD wettable powder was also optimized by carriers screening,additives screening and mixture design.Extreme vertex design was used to determine the optimal mixture proportion of silica white,kaolinite and additives 2020.It was proved that the suitable contents of silica white,kaolinite and adjuvant 2020 in 5%CYC/?-CD WP were 0.5572,0.4141 and 0.0287,respectively.Under these conditions,predicted wetting time,suspensibility and pH value of 5%CYC/?-CD WP were 15 s,90.39%,7.63,respectively.Furthermore,the experimental results were in good agreement with those predicted.In the field control efficiency test,both 5%CYC/?-CD WP and 25%CYC WP worked well with a suitable dose of 90 g/ha,however 5%CYC/?-CD WP showed a better control efficiency.