Specific refractive index increments of inulin

Abstract

The specific refractive index increments (dn/dc) of inulin in water, at 25°C, were measured at different wavelengths (436, 546 and 589 nm) using a BP-differential refractometer. The dn/dc at the operating wavelength (633 nm) of the laser light scattering photometer was calculated by an approximate method. This value can be used to determine the absolute molar mass and the second virial coefficient of inulin by light scattering photometry.