USAXS studies of monosaccharide gels. I. Dependence of the glucofuranose-based gel structure on the gelator concentration

Glucofuranose-derivative based gels with various gelator concentration were studied using ultra-small angle X-ray scattering (USAXS) in the scattering vector range 0.0028-0.25 nm(-1). A complex method of data processing was applied to extract the structural parameters of the gelator, such as the mass fractal and surface fractal dimensions, d(m) and d(s), respectively, the radius of gyration, R-g, the distance distribution function, p(r), as well as the volume distribution function, D(R), of particles forming aggregates. The results of these analyses show that the aggregate structure changes with the gelator concentration: when it increases, the size of the aggregates decreases, rough aggregates of the fractal type evolve to better developed smooth ones, and their shape changes from disk-like to rod-like. These results suggest that only two different types of aggregates are formed depending on the gelator concentration, and a gradual change between them is observed. (c) 2006 Elsevier B.V. All rights reserved.