The highly cross-linked poly(ε-caprolactone) as biodegradable implants for prostate cancer treatment-part I: Synthesis and in vivo degradation

Highly cross-linked poly(ε-caprolactone) (PCL) was fabricated via the ring-opening (co)polymerization of ε-caprolactone with/without 30 mol% trimethylene carbonate (TMC), using 4~6mol% bis-CL or bis-TMC as the cross-linker. The in vivo degradation behavior of the obtained cross-linked PCL implants was investigated via the subcutaneous implantation into the back of rats to evaluate the possibility of the cross-linked PCL as the carrier material of the biodegradable implants. The results showed that the obtained cross-linked PCL implants had a slow degradation rate with mass loss of less than 13% after 48 weeks of degradation in vivo. The introduction of 30 mol% TMC endowed a faster degradation rate to the cross-linked PCL with a mass loss of 19.69% after 48 weeks. Furthermore, the cross-linked PCL implants presented good form-stability with no observation of deformation was found during the in vivo degradation. The SEM observation indicated that the degradation of cross-linked PCL in vivo occurred via the surface erosion mechanism. The cross-linked PCL had great potential application as the carrier material for the long-term biodegradable implants.