Microfluidic preparation of chitosan–poly(acrylic acid) composite microspheres with a porous surface structure

Abstract

This article presents a facile microfluidic method to prepare monodispersed chitosan–poly(acrylic acid) composite microspheres by combining chemical crosslinking and solvent evaporation. The prepared microspheres had a porous surface and compact core, and the porous surface would become compact as the solidification time increased. Structures of the composite microspheres were successfully regulated by altering solidification time and dosage of the crosslinker glutaraldehyde. The chitosan–poly(acrylic acid) composite microspheres with a porous surface were used for the immobilization of glucose isomerase. Immobilized glucose isomerase showed good reusability and operational stability. High enzyme activity was maintained in the temperature range of 60 °C to 80 °C and in the pH range of 6.0 to 8.0. Increased thermal stability and pH stability were both realized by loading glucose isomerase on the composite microspheres.