| Pickering emulsion,a kind of emulsion stabilized by the solid particles absorbed at the air-solid or oil-water interface,which shows great potential applications in food,comestics,chemical engineering,pharmaceutics and novel functional materials due to the characteristics of small amout of particles,adjustable wettability,the high stability,environmental friendliness,green pollution-free and eazy recovery.This thesis aims to construct Pickering emulsion microreactors and enzyme-loaded colloidosomes with Pickering emulsion as template,and systemtically study the colescence theory of light and magnetic dual-responsive Pickering emulsion microreactors,magnetically responsive Pickering emulsions as bioreactor anaerobic culture of the bacterium and enzyme-loaded colloidosomes for catalyzing biphasic reaction at Pickering emulsion droplet interface,which provide a new idea for emulsion microreactors in the field of chemical and bioscience and enzyme-loaded colloidosome in the field of enzyme catalyzed reactions.In the research of light and magnetic dual-responsive Pickering emulsion microreactors,a new statege for light-triggering Pickering emulsion micrroreactor coalescence to induce chemical reaction and coalescence mechanism is proposed.Light and magnetic dual-responsive microreactors are stabilized by co-adsorption of hydrophilic Fe3O4 and hydrophobic TiO2 nanoparticles at the oil-water interface.Firstly,the magnetic response of the emulsion droplets are investigated under the applied magnetic field,then the behavior of UV trigger induce drop colescence-triggered reaction forming CaCO3 is investigated by encapsulating the CaCl2 and Na2CO3 aqueous into two kinds of emulsion droplets respectively.Thiss research shows that the two emulsion droplets can close to each other by applying the external magnetic field,the changes in the wettability of s-TiO2 nanoparticles causing the particles to desorb from oil-water interface and trigger coalescenc to form CaCO3.In addition,a model is selected to analyze the coalescence mechanism of the Pickering emulsion microreactor.The results of this study have a wide application prospect in the construction of multiple fuctional Pickering emulsion and materials.In the research of magnetic responsive Pickering emulsion microreactors for anaerobic cultures,the magnetic responsive Pickering emulsion microreactors are stabilized by 6C-Fe3O4 nanoparticles,and the latic acid bacteria is encapsulated in the internal phase of emulsion microreactor,after that the growthing of bacterial in Pickering emulsion droplet microreactors is explored by methyl red test.This study demonstrates that the latic acid bacteria can grow in 6C-Fe3O4 particle-stabilized Pickering emulsion droplet microreactors.Compared with conventional bacterial culture,Pickering emulsions provide individual compartmentalized space,good effect of heat and mass transfer,thus the bacterial can grow rapidly.More importantly,the magnetic responsive Pickering emulsion droplets can effectively avoid the possibility of the bacterial being contaminated during the transfer process,and the particle emulsifiers can be recoverd by breaking the emulsion droplets under the magnetic field.In the research of preparing enzyme-loaded colloidosomes via a Pickering emulsion template for enzymatic reaction,the multi-shelled enzyme-loaded colloidosomes are formed by self-assembling the lipase molecules and SiO2 nanoparticles in the good biocompatible system containing water/n-butanol,and the colloidosomes are used to study the cross-interface enzyme catalysis reaction.Furthermore,the enzyme-catalyzed reaction of colloidosomes can be separated and recoverd by the method of centrifugation,and it still maintaines high catalytic activity even after eight reaction cycles.In addition,this study found that the prepared enzyme-loaded colloidosomes exhibit a high encapsulation effeicency and encapsulation capality for encapsulation of bioactive substances.The scanning electron microscopy(SEM)and laser confocal microscopy(CLSM)observations demonstrate that the colloidosome posseses multiple layers of shell and the lipase are located in both shell and inner chamber.This stduy provides a good carrier for encapsulation of bioactive substance and the enzyme-loaded colloidosomes provide valuable method and idea for Pickering emulsion across interface enzymatic reactions. |
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