The optical rotation of anisotropic macromolecules depends on the direction of propagation of linearly polarized light through the molecule. The molecular optical activity is thus a tensor property, the components of which characterize the molecular structure. A study is reported in which these components have been measured for three polypeptides in helix-promoting solvents. These were poly(),-benzyl-Lglutamate), poly(7-benzyl-D-glutamate) and poly(fl-benzyl-L-aspartate). The measurement technique involved imposing orientational alignment upon the molecules. This alignment was achieved using pulsed electric fields and the optical rotation recorded over a range of visible light wavelengths. From the rates of response to the field changes, helical lengths were obtained. The implications for molecular conformations are discussed.
Посилання на статтю:
Experimental study of electro-optical rotation of helical polypeptides / K. Weir* // Polymer. – 1992. – Vol 33. – P. 2287-2291.