Electrospun Chitosan Microspheres for Complete Encapsulation of Anionic Proteins: Controlling Particle Size and Encapsulation Efficiency

Abstract

Abstract. Electrospinning was employed to fabricate chitosan microspheres by a single-step encapsulation of proteins without organic solvents. Chitosan in acetic acid was electrospun toward a grounded sodium carbonate solution at various electric potential and feeding rates. Electrospun microspheres became insoluble and solidified in the sodium carbonate solution by neutralization of chitosan acetate. When the freeze-dried microspheres were examined by scanning electron microscopy, the small particle size was obtained at higher voltages. This is explained by the chitosan droplet size at the electrospinning needle was clearly controllable by the electric potential. The recovery yield of chitosan microspheres was dependent on the concentration of chitosan solution due to the viscosity is the major factor affecting formation of chitosan droplet during curling of the electrospinning jets. For protein encapsulation, fluorescently labeled bovine serum albumin (BSA) was codissolved with chitosan in the solution and electrospun. At higher concentration of sodium carbonate solution and longer solidification time in the solution, the encapsulation efficiency of the protein was confirmed to be significantly high. The high encapsulation efficiency was achievable by instant solidification of microspheres and electrostatic interactions between chitosan and BSA. Release profiles of BSA from the microspheres showed that the protein release was faster in acidic solution due to dissolution of chitosan. Reversed-phase chromatography of the released fractions confirmed that exposure of BSA to acidic solution during the electrospinning did not result in structural changes of the encapsulated protein.

Chitosan microparticles loaded with yeast-derived PCV2 virus-like particles elicit antigen-specific cellular immune response in mice after oral administration

“…This experiment confirmed that the PCV2 antigen was displayed on the microparticle surface (Figure 2 A). Similar fluorescent data have been observed for other chitosan microparticle formulations [ 22 ].…”

Electrohydrodynamic atomization: A two-decade effort to produce and process micro-/nanoparticulate materials

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Janus Self‐Propelled Chitosan‐Based Hydrogel Spheres for Rapid Bleeding Control

“…The increased hydrogel sphere size was attributed to the addition of CaCO 3 powder into the spinning solution, which might affect the viscosity and conductivity of monomer solution during the spinning process and provide mechanical support for photocrosslinking. [ 32 ] The schematic for the production of a hydrogel shell with a core of the J‐CMH@CaCO 3 was illustrated in Figure 2d . That is, the diffusion of Ca 2+ made the CCS form the shells, and they were used as the templates to produce the hydrogel spheres.…”