Study on a novel copper-containing composite for contraception

BackgroundThe copper-containing intrauterine devices (Cu-IUDs) are being increasingly used worldwide as an effective contraception for family planning. To avoid abnormal bleeding, pain, partial and complete expulsion, which are associated with the burst release of cupric ions during the first few days, a novel cross-linked composite based on polyvinyl alcohol (PVA) that contained cupric ions, but not metallic copper, was developed by our research team.Study DesignAs a logical extension of our previous work, the corrosion products and release behavior of this composite after immersing in simulated body fluid (SBF) for 1 year were studied by X-ray fluorescence spectroscopy (XRF), X-ray diffraction (XRD) and atomic absorption spectrophotometry (AAS).ResultsNo other new elements, such as P, Cl and Ca, appeared on the surface of the composite, and no Cu2O was formed after immersing in SBF for 1 year, indicating that the effectiveness of copper can be greatly improved. Furthermore, no significant change on time dependence was found for the release rates of cupric ions in the composite compared with that of metallic copper, suggesting the absent burst release of cupric ions in the composite.ConclusionThe present in vitro long-term data suggest that this novel copper-containing composite has potential as a substitute for conventional materials used in the manufacture of IUDs.