Fabrication and permeability characteristics of microdialysis probe using chitosan nanoporous membrane

Abstract

In this article, a nanoporous chitosan polymer membrane was successfully produced and applied as microdialysis membrane for in vitro sampling of biomolecules. With the use of nanoparticle leaching technique, porogenic gelatin nanoparticles formed nanopores in the chitosan-based membrane to create a secure implantable nanoporous membrane for biomolecule sampling. The gelatin nanoparticles size was in the range of 45 to 70 nm, and the pore size of the chitosan membrane was around 40 to 100 nm. The porosity of membrane was found to be dependent on the mixing ratio of chitosan solution and gelatin nanoparticles solution. The results of diffusion study showed that we can alter the mixing ratio of porogen to achieve size-selective molecular diffusion, which means that the porosity and cut-off size of porous membrane can be controlled. The recoveries of the probe fabricated from the chitosan-based membrane were examined for four different model compounds of different molecular weights: 2-NBDG, substance P, TNF-α, and FITC-BSA. The microdialysis probes showed linear responses and substantial recovery to various concentrations of biomolecules. These results indicated that the microdialysis probe constructed by chitosan nanoporous membrane could sample and monitor the biomolecules in vitro and has the potential for the application in vivo. © 2014 Yun-Ju Chuang et al.