Construction Of High-temperature-Resistant Micro Compartments Based On Natural Polysaccharides

The micro compartments based on natural materials combine the characteristics of stable,easy-to-design,functional,and excellent biocompatibility.Since most of these capsules are based on protein,very mild environmental conditions are required,which severely limits the application of natural material capsules.Therefore,the use of suitable natural materials to build micro compartments with stronger property of stability can inspire research towards potential use of them in both scientific research and practical applications.Based on the background above,using dextran,one of natural polysaccharides,through the carboxylation and amination of dextran and grafting polymer PNIPAAm,microcapsule building blocks with amphiphilicity was prepared.By the method of Pickering Emulsion,Dextran-NH2/PNIPAAm building blocks were formed to micro compartments called Dextranosomes by self-assembly.Then we investigated the influences about concentration of the building blocks,the ratio of dextran to the polymer,and the volume ratio of the aqueous phase to the oil phase towards the formation of single-chamber dextranosomes.After the construction of the micro compartments,the thermal stability of dextranosomes was characterized by optical microscopy and fluorescence microscopy.Neither the structure of dextranosomes fused or disintegrated during the thermal treatment,nor contents exchange or leakage occurred.It can be shown as well that the building blocks can also self-assemble at a high temperature to form a stable capsule structure.Finally,the issue of polymerase chain reaction in capsules demonstrates that Dextran-NH2/PNIPAAm micro compartments have the ability to carry complex components under high temperature conditions and can be used as of microscale reactors under relatively high temperature conditions.