Study on molecular structural characteristics of tea polysaccharide

Tea polysaccharide (TPS) is attracting more attention gradually due to its particular biological properties. However, molecular characteristics of TPS are unclear since appropriate method is still absent. So, study on the molecular characteristics of TPS was carried out by high-performance size-exclusion chromatography (HPSEC), multi-angle laser light scattering (MALLS) and viscosimetry. The results showed that the molar masses of TPS ranged from 2.287 x 10(5) to 2.762 x 10(5) g mol(-1), the RMS radii distributed from 132.1 to 145.9 nm, and M-w/M-n is 1.028. The Mark-Houwink equation was established as [eta] = 0.5423(w)(0.5379), and the intrinsic viscosity and molecular chain parameters were as follows: [eta] = 1.007 dLg(-1), k(H) = 0.845, k(K) = 0.387, alpha = 0.5379, K= 0.5423.In addition, based on the slope of the RMS radius versus molar mass conformational plot being 0.24 +/- 0.00, we suggest that the molecular morphology of TPS is a homogeneous and spherical polymer with branch in solution. (C) 2010 Elsevier B.V. All rights reserved.