Biocompatible microcapsules with a water core are widely used to encapsulate hydrophilic actives.Here,a facile method to fabricate monodisperse biocompatible microcapsules with a water core in large quantity is report...Biocompatible microcapsules with a water core are widely used to encapsulate hydrophilic actives.Here,a facile method to fabricate monodisperse biocompatible microcapsules with a water core in large quantity is reported.Microfluidic technology is utilized to emulsify the inner aqueous phase containing the shell polymer into monodisperse drops in the outer oil phase.As the cosolvent in the inner aqueous phase diffuses into the outer oil phase,the solubility of the shell polymer decreases,which eventually precipitates.Since the shell polymer,shellac,contains both hydrophilic and hydrophobic groups,it tends to wet both the inner aqueous phase and the outer oil phase,thus forming a solid shell at the periphery of the drop.We show that the diffusion rate of hydrophilic molecules encapsulated in the water core decreases as their molecular weight increases and the property of the microcapsules could further be modified by polyelectrolyte multilayer coating.These microcapsules are fabricated using FDA-approved polymer and non-toxic solvents and are of great use in drugs,cosmetics and foods.展开更多
基金the Youth Founds of the State Key Laboratory of Fluid Power and Mechatronic Systems(Zhejiang University)“Thousand Talents Program” for Distinguished Young Scholars+2 种基金C.-X.Zhao acknowledges financial support from Australian Research Council through the award of a 2014 ARC Future Fellowship(No.FT140100726)supported by the National Science Foundation of U.S.A.(No.DMR-1310266)the Harvard Materials Research Science and Engineering Center(No.DMR-1420570)
文摘Biocompatible microcapsules with a water core are widely used to encapsulate hydrophilic actives.Here,a facile method to fabricate monodisperse biocompatible microcapsules with a water core in large quantity is reported.Microfluidic technology is utilized to emulsify the inner aqueous phase containing the shell polymer into monodisperse drops in the outer oil phase.As the cosolvent in the inner aqueous phase diffuses into the outer oil phase,the solubility of the shell polymer decreases,which eventually precipitates.Since the shell polymer,shellac,contains both hydrophilic and hydrophobic groups,it tends to wet both the inner aqueous phase and the outer oil phase,thus forming a solid shell at the periphery of the drop.We show that the diffusion rate of hydrophilic molecules encapsulated in the water core decreases as their molecular weight increases and the property of the microcapsules could further be modified by polyelectrolyte multilayer coating.These microcapsules are fabricated using FDA-approved polymer and non-toxic solvents and are of great use in drugs,cosmetics and foods.
