Chitosan was prepared from crab shell. Different derivatives of chitosan e.g. phosphate, cyanoethyl and carboxymethyl chitosan are prepared. Molecular structure of chitosan and its derivatives was fallowed by infrared spectroscopy. A new band at 1715cm -1 (carboxyl group), at 2253cm -1 (cyano group) and at 1200cm -1 for (c-o-p) in spectra of carboxymethyl chitosan, cyanoethyl chitosan and chito...

In this paper, the effect of chitosan molecular weight on the characteristics (size, encapsulation efficiency, zeta potential, surface morphology and release rate) of vitamin C encapsulated tripolyphosphate cross-linked chitosan (TPP-chitosan) microspheres. The molecular weight of chitosan had a noticeable influence on the size, encapsulation efficiency, zeta potential, surface morphology and c...

background: considering the common origin of skin and peripheral nervous system, a tube of dermal layer of skin hypothetically can be an ideal conduit for nerve reconstruction. an experimental study performed to evaluate the nerve regeneration of efficacy into a dermal tube. methods: sixty male wistar rats were used. a 10 mm gap was produced in right sciatic nerves. in group a the autogenous ne...

The concept of the “work” in art differs from and challenges traditional concepts of the “work” in bibliography. Whereas the traditional bibliographic concept of the work takes an ideational approach that incorporates mentalist epistemologies, container-content metaphors, and the conduit metaphor of information transfer and re-presentation, the concept of the work of art as is presented here be...

OBJECTIVES We sought to examine risk factors for pulmonary conduit failure or dysfunction in infants less than age 2 years at initial implantation. METHODS From 2002 to 2005, 241 children at 17 institutions were discharged alive after initial pulmonary conduit insertion. Initial conduit type was pulmonary allograft in 37%, aortic allograft in 29%, bovine jugular venous valved conduit in 25%, ...

The data shown in this article are related to the subject of an article in Carbohydrate Polymers, entitled "Synthesis and characterization of chitosan alkyl urea" [1]. 1H NMR and 13C NMR spectra of chitosan n-octyl urea, chitosan n-dodecyl urea and chitosan cyclohexyl urea are displayed. The chemical shifts of proton and carbon of glucose skeleton in these chitosan derivatives are designated in...

Chitosan is soluble in most acids. The protonation of the amino groups on the chitosan backbone inhibits the electrospinnability of pure chitosan. Recently, electrospinning of nanofibers based on chitosan has been widely researched and numerous nanofibers containing chitosan have been prepared by decreasing the number of the free amino groups of chitosan as the nanofibiers have enormous possibi...