Motion of chains in polypeptide brushes

A simple model of a polypeptide multi-chain layer was designed and studied. Each chain was constructed on a flexible [310] lattice and terminally attached to an impenetrable surface. The chains consisted of hydrophilic and hydrophobic amino acid residues. The force field consisted of the long-range contact potential between polymer segments and the short range repulsion. The Monte Carlo simulations of this model were carried out using the Metropolis algorithm. The influence of the grafting density, the temperature and the sequence of the chain on the static properties of the system were studied. The size and structure of the polymer film formed near the surface were investigated. The low temperature structures of brushes were described and compared. We found that the influence of temperature on the size and structure of the dense brushes was rather small. The temperature dependences of the diffusion coefficient were studied and compared for different sequences of amino acid residues.