Preparation method of chitosan hollow and core-shell microcapsule with pH-sensitive burst release property

Abstract

The invention provides a preparation method of chitosan hollow and core-shell microcapsules with pH-sensitive burst release property. The method comprises the following steps: (1) preparing a water phase fluid, an inner oil phase fluid and an outer oil phase fluid; (2) injecting the inner oil phase, the water phase and the outer oil phase into an injection tube, a transition tube and a collectingtube of a capillary microfluidic device respectively, to form a monodisperse oil / water / oil multiple emulsion; then introducing the monodisperse oil / water / oil multiple emulsion to a culture dish through a pipe connected with the exit of the collecting tube; and allowing the monodisperse oil / water / oil multiple emulsion to stand in the culture dish for at least 0.5 hour to form a chitosan core-shellmicrocapsule blank; and (3) washing the chitosan core-shell microcapsule blank with an isopropanol solvent or a composite solve composed of isopropanol and ethyl acetate to remove the inner and the outer oil phases, and then washing with deionized water to obtain a chitosan hollow microcapsule; and washing the chitosan core-shell microcapsule blank obtained in the step (2) with an aqueous solution of surfactant to remove the outer oil phase, and then washing with deionized water to obtain a chitosan core-shell microcapsule.

Description

technical field [0001] The invention belongs to the field of preparation of chitosan microcapsules, in particular to a preparation method of chitosan hollow and core-shell microcapsules with pH burst release characteristics. Background technique [0002] Chitosan is a cationic polysaccharide, which not only exhibits good biological activity, biocompatibility and biodegradability, but also has anti-ulcer and antibacterial properties, so chitosan microcapsules can be used as drug carriers. [0003] In the prior art, the preparation methods of chitosan microcapsules include physical aggregation method, layer-by-layer self-assembly (LBL) method and chemical cross-linking method. The traditional coacervation method (see S.S.Deveci and G.Basal, Colloid.Polym.Sci., 2009, 287, 1455) is to mix chitosan with an aqueous solution of negatively charged polyelectrolyte, and the microcapsules generated by coagulation usually require Stabilized by heat treatment, crosslinking or desolvatio...

AI Technical Summary

Problems solved by technology

[0005] The combination of chemical cross-linking method and Shirasu porous glass (SPG) membrane emulsification technology can be used to prepare monodisperse chitosan microspheres with hollow structure (see W.Wei, L.Yuan, G.Hu, L.Y.Wang, H.Wu , X.Hu, Z.G.Su and G.H.Ma, Adv.Mater., 2008, 20, 2292), this method requires two-step cross-linking, thus increasing the preparation cycle, in addition, the current chemical cross-linking method commonly used glutaraldehyde as Cross-linking agent, there are certain health and environmental hazards

Images