Release of copper and indomethacin from intrauterine devices immersed in simulated uterine fluid.
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.
Zhou
Xiaowen
X
Department of Pharmaceutics, China Pharmaceutical University, Nanjing, PR China.
Li
Ying
Y
Jiang
Xiaoqun
X
Qiu
Lu
L
Liu
Jianping
J
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*
D003300:Copper; D007213:Indomethacin