title: Release of copper and indomethacin from intrauterine devices immersed in simulated uterine fluid.
abstract: OBJECTIVE
  To study the release of cupric ions and indomethacin from copper-bearing intrauterine devices (Cu-IUDs) and to assess the influence of their surface area of copper and the pH of the test medium on the release of cupric ions.
  
  
  METHODS
  Cu-IUDs were incubated in simulated uterine fluid (SUF). The in vitro release of cupric ions and indomethacin was determined by means of a flame atomic absorption spectrometer and a UV 752 spectrophotometer, respectively, over a period of 220 days. The effect of indomethacin on the pH of the SUF was monitored during the cupric ions release study.
  
  
  RESULTS
  The Cu-IUDs released cupric ions in vitro according to a biphasic pattern. After an initial burst release, the rate slowed down and then became steady. The release of indomethacin from two medicated Cu-IUDs was biphasic and, in both cases, in accordance with the in vitro dissolution model of the drug. The surface area of copper of Cu-IUDs and the pH change induced by indomethacin incorporated in their frame affected the release rate of copper (p < 0.05).
  
  
  CONCLUSIONS
  The surface area of the copper and the pH of the test medium modulate the in vitro release of cupric ions from Cu-IUDs.
authors.affiliation: Department of Pharmaceutics, China Pharmaceutical University, Nanjing, PR China.
authors.forename: Xiaowen
authors.initials: X
authors.lastname: Zhou
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.forename: Xiaoqun
authors.initials: X
authors.lastname: Jiang
authors.forename: Lu
authors.initials: L
authors.lastname: Qiu
authors.forename: Jianping
authors.initials: J
authors.lastname: Liu
mesh_terms: D001826:Body Fluids / Q000378:metabolism*; D003300:Copper / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007213:Indomethacin / Q000493:pharmacokinetics*; D007435:Intrauterine Devices, Copper; D013054:Spectrophotometry, Atomic / Q000379:methods; D014599:Uterus / Q000378:metabolism*
chemical_list: D003300:Copper; D007213:Indomethacin