Click Chemistry In Cell Surface Nanofunctionalization

Cells have unique biofunctions in many industrial applications.Inspired by nature,cell surface nanofunctionalization technology by encapsulating cell in nanomaterials,can combine the biofunctions of cells with nanofunctions of nanomaterials,which can not only enhance cell viability in hostile environments,but also endow cells new nanofunctions.However,due to the weak interactions and the complexity of nanomaterials,cell surface nanofunctionalization technology that with good stability and universality is most desired.Click chemistry can quickly and reliably synthesize complex compounds with micromolecules,which is the main method to synthesize natural products and organisms in nature.In this thesis,we present a new way to self-assemble the nanomaterials on yeast cell surface based on click reaction between phenylboronic acid and polysaccharides of cells.The formed nanoshell possess the porous structure which benefits the mass transfer,and also enhances the cell stability under hostile environments,such as high temperature,UV-light,lyticase,osmotic shock and long-term stability.Moreover,the encapsulated cells show the reversibility and the cell behavior is tested in real time.More details are shown as follows:Firstly,we successfully encapsulate yeast cells with mesoporous silica nanoparticles(MSNs).MSNs are modified by phenylboronic acid,and self-assemble of yeast cell surface to form the nanoshell through the click reaction between phenylboronic acid and polysaccharides of cells.The nanoshell shows good diffusivity of glucose,and enhances the cell stability,while the encapsulated cells maintain the 96?1% of initial activity.The nanoshell can reversibly detach/assemble on cell surface with the additional/removal of glucose.Secondly,we successfully encapsulate yeast cells with reduced graphene oxide(rGO).The cell surface is modified by amino groups through the click reaction between phenylboronic acid and polysaccharides of cells.After that,rGO materials assemble on the cell surface to form the nanoshell.The nanoshell with radial structure shows good biocompatibility,and can enhance cell stability.The encapsulated cells maintain higher activity under long-term storage that the encapsulated cells remain 82±4% of the initial activity after 8 days without any nutrition.After composited by gold nanoparticles,the resistance value decrease from 1.57 M? to 0.38 M?.The cell behavior is tested in real time by electrochemical workstation.Above all,the single cell encapsulation technique of click chemistry reaction can not only promote strong binding to form the highly stable nanoshells,but also is good biocompatible to cells due to its soft and rapid reaction.This provides a highly new,versatile tool in biotechnology for single cell encapsulation and smart cellular application.