Degradation of high-molecular-weight hyaluronan by hydrogen peroxide in the presence of cupric ions

Dynamic viscosity (η) of the high-molecular-weight hyaluronan (HA) solution was measured by a Brookfield rotational viscometer equipped with a Teflon cup and spindle of coaxial cylindrical geometry. The decrease of η of the HA solution, indicating degradation of the biopolymer, was induced by a system containing H2O2 alone or H2O2 plus CuCl2. The reaction system H2O2 plus CuCl2 as investigated by EPR spin-trapping technique revealed the formation of a four-line EPR signal characteristic of a DMPO–OH spin adduct. Thus, hydroxyl radicals are implicated in degradation of high-molecular-weight HA by the system containing H2O2 and CuCl2.

Figure optionsDownload as PowerPoint slide