Chitosan, oxygen permeability

A novel organic (chitosan) and inorganic (tetraethyl orthosilicate) composite membrane has been prepared, which is pH sensitive and drug permeable [258]. The latter possibly involved in ionic interactions. By plasma source ion implantation technique, the adhesion between linear low-density polyethylene and chitosan could be improved [259]. Such bilayer films showed 10 times lower oxygen permeability, a property of use in food packaging applications. These multilayer films were easily recyclable. 

Bai, R.K., Huang, M.Y., and Jiang, Y.Y. 1988. Selective permeabilities of chitosan-acetic acid complex membrane for oxygen and carbon dioxide. Polymer Bull. 20, 83-88. 

The nanoparticles should be biocompatible. This requires a matrix that has to be permeable to water and oxygen and has to permit the ROS to diffuse out of the matrix. Water solubility can be imparted to the nanoparticles e.g. by using a silica layer, polyethyleneimine, polyethylene glycol derivatives, or chitosan. 

Chitosan OH >OH OH NHj NHi NHi L Jn Purified qualities of chitosans are available for biomedical applications. It is nontoxic, biodegradable, and biocompatible. Antimicrobial and antifungal activities Highly permeable to water vapor. Excellent oxygen barrier properties. Good mechanical properties. Good antimicrobial activity. 

Chitosan forms a coating on fhiit and vegetable, and thus the respiration rate of fhiit and vegetable was reduced by adjusting the permeability of carbon dioxide and oxygen [37]. Chitosan is also used in many postharvest... 

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