Cupric ion release controlled by copper/low-density polyethylene nanocomposite in simulated uterine solution.

The Cu2+ release rate of novel copper/low-density polyethylene composites as an intrauterine device material in the simulated uterine solution was investigated for 280 days. The corrosion products of these composites were identified by the X-ray diffraction method. The distributions of the copper phase and the cuprous oxide phase at different corrosion depths in the composites were measured by the internal standard method. For comparison, copper particles of two sizes were embedded in a polyethylene matrix to form composites. The average copper particle diameter of the nanocomposite was 30 nm, while that of microcomposite was 52 microm. Mechanism of Cu2+ release controlled by the nanocomposite revealed that many clusters composed of copper nanoparticles, which were observed by the field emission scanning electron microscopy in the nanocomposite, led to the formation of large amounts of Cu2O and consequently facilitated the Cu2+ steady release. A scanning electron microscope with energy dispersive X-ray microanalysis mapping technique (SEM/EDX) was employed to measure the corrosion depth and to calculate the life span of the nanocomposite. The result that the nanocomposite displayed a near zero-order release after a month of incubation indicated that the Cu2+ release behavior controlled by nanocomposite was remarkably superior to that by microcomposite. 2006 Wiley Periodicals, Inc.