Thermal oxidation of copper pipes for CuIUD and their Cu~（2＋） ions release in vitro
Copper intravas uterine device（CuIUD） initially implanted in uterus often brings the ＂burst release ＂ of Cu2＋ in clinic.In order to improve the corrosion resistant of Cu and reduce the release rate of Cu2＋,a series of oxidation processes,heating at 250-350 ℃ for 30-120 min,were employed to form a copper oxide layer on surface of the copper pipes in advance.The morphology of oxidized samples was observed by SEM and the phase components of the oxidation layers were analyzed by XRD.The corrosion potential,corrosion current density and alternating current impedance of the samples treated by different oxidation processes were examined by electrochemical tests.The optimized oxidation process is heating at 275 ℃ for 30 min.And furthermore,the release rate of Cu2＋ of the sample treated at 275 ℃ for 30 min was researched.The results show that a compact and uniform oxidation layer composing of Cu2O and CuO forms on the surface of the copper pipes treated by the optimized oxidation process,and the release rate of Cu2＋ of the processed sample is significantly lower than that of the samples which are commonly used in clinic.So the ＂burst release＂ phenomenon of Cu2＋ for CuIUD used in clinic could be evidently improved by oxidation treatment.
NETL
NSTL
万方数据
维普
