Birefringence and Orientation-Rate of the Leptones of Protoplasm

Abstract

PRESENT knowledge indicates that the submicro-scopic or 'leptonic' state of organised gels¹ consists of a framework of reciprocally associated macromolecules or molecular bundles (micelles). Their orientation-rate within the gels, as observed in polarized light, decides whether there are formed anisotropic gels in which the particles (leptones) are arranged parallel to each other, or isotropic gels in consequence of perfect disorientation of the leptones. Between these two limiting cases, there are many textures with differently graded orientation-rates. If a system contains imperfectly oriented leptones, the orientation-rate, and hence the birefringence, will be increased by tension². Thus the birefringence will reach a maximum when the leptones are maximally oriented. But the theoretical relation between birefringence and orientation-rate is somewhat indefinite, for even in the case of perfect orientation the rate of grid-like disposition cannot be comprehended apart from the remainder. Moreover, isotropy includes cases of perfect disorientation as well as adjacent organisation in the immediate environs (Nahordnung). Further complications in consequence of different rates of swelling and extension cannot be taken into consideration here. The distribution function of O. Kratky, P. H. Hermans and co-workers², defining the frequent repetition of the different directions of leptones, has been obtained from the extension-rate of the gels and their orientation state before the extension. But with biogels, the deformation-rate during the unextended, that is, isotropic, state is not appreciable. Frey-Wyssling² has derived expressions describing the field or cone of scattering of leptones by means of a single angle. This method, however, gives only a comparative measure of the increase of orientation. I have now been able to investigate the streaming birefringence of protoplasm and to calculate the orientation-rate of its leptones.