Polymeric Implants for the Delivery of Green Tea Polyphenols

Polymeric implants (millirods) have been tested for local delivery of chemotherapeutic agents in cancer treatment. Modeling of drug release profiles is critical as it may provide theoretical insights on rational implant design. In this study, a biodegradable poly (ε-caprolactone) (PCL) polymeric implant delivery system was tested to deliver green tea polyphenols (GTPs), both in vitro and in vivo. Factors including polymer compositions, supplements, drug loads, and surface area of implants were investigated. Our data showed that GTPs were released from PCL implants continuously for long durations, and drug load was the main determining factor of GTPs release. Furthermore, rates of in vitro release and in vivo release in the rat model followed similar kinetics for up to 16 months. A mathematical model was deduced and discussed. GTP implants have the potential to be used systemically and locally at the tumor site as an alternative strategy.