Chitosan hydrogel micro-bio-devices with complex capillary patterns via reactive-diffusive self-assembly

Abstract

We present chitosan hydrogel microfluidic devices with self-assembled complex microcapillary patterns, conveniently formed by a diffusion-reaction process. These patterns in chitosan hydrogels are formed by a single-step procedure involving diffusion of a gelation agent into the polymer solution inside a microfluidic channel. By changing the channel geometry, it is demonstrated how to control capillary length, trajectory and branching. Diffusion of nanoparticles (NPs) in the capillary network is used as a model to effectively mimic the transport of nano-objects in vascularized tissues. Gold NPs diffusion is measured locally in the hydrogel chips, and during their two-step transport through the capillaries to the gel matrix and eventually to embedded cell clusters in the gel. In addition, the quantitative analyses reported in this study provide novel opportunities for theoretical investigation of capillary formation and propagation during diffusive gelation of biopolymers.

Bio-inspired flow-driven chitosan chemical gardens

“…The interface between the two electrolytes can lead to structural formations, like compact, porous, layered-oriented structures, 16 self-assembled microcapillaries of chitosan hydrogel. 17 Microfluidics 18,19 and dip-coating 20 have also been successfully utilized to create microtubes. The flexibility of the sol-gel process helps in constructing a variety of useful functional materials and morphologies.…”

Oral Lubrication, Xerostomia, and Advanced Macromolecular Lubricants for Treatment of Dry Mouth

“…Chitosan is a cationic mucoadhesive polymer capable of forming strong electrostatic interactions and hydrogen bonding with many other macromolecules [143]. It can be modified with catechol to boost its water solubility and its affinity to glycoprotein [144].…”

Microfluidic Nanoparticles for Drug Delivery

“…Sodium tripolyphosphate is a commonly used chitosan cross-linker, and the ionic gelation reaction between sodium tripolyphosphate and chitosan can be exploited by microfluidic methods to form chitosan NPs for biomedical applications. [127,130] The staggered herringbone micromixer was used for the synthesis of curcumin-loaded chitosan NPs via ionic gelation reaction. [127] The HFF device has also been used to produce chitosan NPs.…”