| With the development of industrialization,a large number of industrial wastewater have been discharged into the body,causing the destruction of the ecological environment and human health.How to deal with water pollution and protect human health has been focused on.The microspheres loaded with protein can be fabricated by coaxial electrospraying for usage in wastewater treatment and medicine field.Coaxial electrohydrodynamic atomization as a valuable application technology,can be used to fabricate microspheres in a single step.Through different shell and core layer materials,a variety of combination applications can be carried out.The microspheres with different particle sizes can be obtained by adjusting the flow rate,voltage and receiving distance.The microspheres with potential application value can be researched and developmented in environment and medicine field.In this study,sodium alginate and calcium chloride were used as initial materials,and(Sodium Alginate-Calcium)SA-Ca gel spheres were fabricated by coaxial electrospraying.Laccase was immobilized with the embedding of SA-Ca gel spheres.A new composite adsorbent was formed by mixing SA-Ca gel spheres and cationic starch with a mass ratio of 1:1.The decolorization of congo red and basic green dyeing wastewater were studied by using new complex adsorbent.The influences of several factors including dosage of adsorbent,adsorption time,pH value of solution,temperature,initial congo red and basic green dyeing wastewater on experiment were investigated,and the experimental conditions were optimized.Meanwhile adsorption dynamics,adsorption thermodynamic,adsorption isotherm were discussed.Through single factor experiment,the experimental results showed that under the optimal immobilized conditions of volume 50mL and speed125r/min,0.6g of adsorbent dosage,30min of adsorption time,initial pH,the temperature30℃,100mg/L of initial congo red dye concentration,the maximum declor rate and adsorption capacity of congo red by complex adsorbent were 96.11%and 164.19mg/g respectively.In addition,under the optimal immobilized conditions of volume 50mL and speed 125r/min,0.5g of adsorbent dosage,40min of adsorption time,initial pH,the temperature 50℃,100mg/L of initial basic green dye concentration,the maximum declor rate and adsorption capacity of basic green by complex adsorbent were 92.04%and92.04mg/g respectively.Thermodynamic studies show that the adsorption isotherms of congo red on new complex adsorbent follow Langmuir isotherms model.The kinetics of adsorption of congo red by new complex adsorbent can be elaborated by pseudo second orderdynamics.The correlation coefficient R~2>0.999,which is much higher than those of pseudo-first-orderdynamics.The equilibrium adsorption capacity calculated by pseudo-second-orderdynamics is much closed to the experimental value q_e.The adsorption of congo red on adsorbent follow the pseudo-second-orderdynamics.(poly(lactic-co-glycolic acid))PLGA microspheres with core-shell structure were fabricated by coaxial electrospraying,and bovine serum albumin was used as a simulate protein durg.Based on the single factor method,the optimum conditions for the preparation of uniform and smooth microspheres were obtained:10%of the concentration,2mL/h and 0.2mL/h of the shell and core injection rate,voltage 10kV and 15cm of distance.The morphology of microspheres were observed by scanning election microscope(SEM),and the diameter of microspheres was analyzed by image J software.The results show that the microspheres have good morphology and uniform particle size.In addition,the BSA-PLGA microspheres were released in vitro,the microspheres showed good release behavior and improved burst phenomenon.The green light of bovine serum albumin(BSA)under excitation wavelength was observed by confocal laser scanning microscopy,and the core-shell structure of BSA-PLGA microspheres were observed.The cytotoxicity of microspheres were detected by MTT assay,and the results show that the blank PLGA core-shell microspheres has no cytotoxicity.BSA-PLGA core-shell microspheres with gel properties show potential application prospect.Polycaprolactone(PCL)core-shell structure microspheres were fabricated by coaxial electrospraying.The optimum conditions were as follows:4%of polycaprolactone concentration,voltage 10kV,1ml/h of shell injection rate,and 15cm of distance.The gel time can be obtained by mixing hyaluronic acid(HA)and glycol chitosan(GC)solution,indicates that hydrophilic core layer gel can be produced after the preparation of microspheres by 27.5min.It was observed that the fabricated microspheres had core-shell structure by fluorescence microscopy and confocal microscopy.The blank PCL microspheres were detected by MTT.The results show that grade of 0 and 1 correspond with cell viability and view no cytotoxicity.The PCL microspheres can be used as loading protein biological carrier materials. |
