50. Louvier-Hernández, José F.; Luna-Bárcenas G.; Thakur, R.; Gupta, Ram B. “Formation of chitin nano-fibers by supercritical antisolvent,” Journal of Biomedical Nanotechnology, vol 1, pages 1-6, January 2005.
Chitin is emerging as a biopolymer of choice because of its potential uses in the numerous biomedical and pharmaceutical applications (e.g., wound dressing, tissue engineering, drug delivery, and antiallergic agent). Nanofibers can provide enhanced properties in many of these applications. Unfortunately, because of the highly cryst. nature, chitin is not sol. in conventional solvents, and it is very difficult to convert it into the fine particulate or fibrous forms. In this work, chitin is dissolved in hexafluoroisopropanol solvent. This soln. is then sprayed into supercrit. carbon dioxide, which rapidly removes the solvent thus pptg. chitin as nanofibers. On the basis of SEM, pptd. chitin is a web of nanofibers of about 84 nm in diam. According to the Fourier-transform IR spectroscopy, chitin mol. structure is preserved during the processing.