Abstract
The in vitro release of testosterone from hydrophobic–hydrophilic copolymerdrug composites in cylindrical form produced by radiation was investigated over a period of 400 days. The release rates could be controlled in the range of approximately 10 to 200 μg/day by changing the monomer composition and kept constantly during the tests. The in vivo release was studied by implanting the composite into rats for a maximum period of 90 days. The results of in vitro and in vivo release of testosterone showed that the in vitro cumulative amount of released drug agreed with that of the in vivo test. The surface of implanted homopolymer carrier was covered by tissue cells and the in vivo released rate was retarded. However, no cell adhesion was observed on the copolymer carrier surface used in this study. Mechanical strength and biocompatibility of copolymers were also evaluated by tensile strength test and microscopic observation, respectively.
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Yoshida, M., Asano, M., Kaetsu, I. et al. In Vivo Release of Testosterone from Hydrophobic–Hydrophilic Copolymer Composites in Long Term Delivery Systems. Polym J 14, 941–950 (1982). https://doi.org/10.1295/polymj.14.941
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DOI: https://doi.org/10.1295/polymj.14.941
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