A novel multinuclear Cu(II) complex of N-cetyl-O-sulfate-chitosan (NCOS) was prepared and structurally characterized by X-ray photoelectron spectroscopy (XPS) and Infrared radiation (IR) spectroscopy. The capability of chelated copper ions to coordinate with the novel ligand was improved 55% over native chitosan. As artificial multinuclear phosphodiesterase, NCOS-Cu(II) complex was adopted to study its catalytic kinetics on hydrolysis of bis(4-nitriphenyl)phosphate (BNPP) in the heterogeneous system. The initial rate of BNPP hydrolysis catalyzed by NCOS-Cu(II) was 7 x 10(4) times higher than that of spontaneous BNPP hydrolysis. The behavior of BNPP catalytic hydrolysis fits Michaelis-Menten kinetics with k(cat) of 2.3 x 10(-5) s(-1), the maximum velocity (V-max) of 2.3 x 10(-9) mol L-1 s(-1) and the Michaelis constant (K-M) of 2.9 x 10(-4) M, respectively. The metal-hydroxyl catalytic mechanism has been proposed. (C) 2010 Elsevier B.V. All rights reserved.