Structural transformations of polysaccharides exposed to CO2-laser radiation

We have used IR spectroscopy to study conformational transformations of polysaccharide macromolecules (dextran, pullulan, amylose, and microcrystalline cellulose) and changes in their structural ordering when exposed to cw emission of a CO₂ laser. We have established that the structures of conformationally labile polysaccharides are the most sensitive to laser radiation. The effect of laser treatment is greatest for lower molecular weight polymers. We have observed for the first time changes in the conformational states of dextran macromolecules in the direction of an increase in the structural ordering when exposed to emission from a CO₂ laser. This quite different from purely thermal treatment, where disordering of the polysaccharides structure occurs. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 2, pp. 164–169, March–April, 2006.