Molecular dynamics study of sucrose aqueous solutions: From solution structure to transport coefficients

• Development of the accurate MD model for carbohydrates is important for the food and pharmaceutical industries. • Four stable sucrose conformations are shown in the solution, which confirm previous experimental and simulation data. • Equation of state, viscosity and diffusion coefficients are well reproduced by the model. • The increase of the sucrose concentration above 40% causes the change of boundary condition in Stokes-Einstein formula. In this work, we study the applicability of the equilibrium molecular dynamics methods for the prediction of solution structure, equation of state and transport properties of sucrose aqueous solution for various concentrations and temperatures. The OPLS-AA force field with 1.14*CM1A charge corrections is used to describe the interactions in the model. We analyze the prediction power of the model against the experimental data and simulation results, obtained previously in CHARMM, OPLS-AA, GLYCAM06 and their modifications. The glycosidic linkage conformations of sucrose in solution are found. Their independence from the sugar concentration and the appearance of the conformation region at temperatures from 283 K to 308 K are observed. Sucrose solution densities are calculated for different sugar concentrations and temperatures. The obtained viscosities and sucrose diffusion coefficients match the experimental data at low sucrose concentrations, and diverge within 41% from the experiment as the concentration increases. The change of boundary condition in Stokes-Einstein formula is observed with an increase of the sucrose concentration above 40%.