Decomposition Behavior of Solid Peroxides: Effect of Ph, Ions and Buffer Composition

The ability of solid peroxides to provide sustained release of both oxygen and H 2 O 2  as well as other reactive oxygen species makes them potentially suitable for different therapeutic applications. ROS-related therapies and oxygen delivery are the most researched functions of solid peroxides. This study compared for the first-time decomposition products of CaO 2 , MgO 2 , ZnO 2 , Na 2 CO 3 .1.5H 2 O 2  and H 2 O 2  across an extreme pH range that could still be considered relevant to some biological applications (pH 5-9). We identified a strong effect of both pH and buffer type on both the extent of decomposition and decomposition product thereby establishing design parameters for intentional release of specific decomposition species. Cytotoxicity surprisingly was not only related to basicity of metal hydroxides. We discuss factors that are likely to alter decomposition profiles between in vitro and in vivo systems.