pH-responsive drug release from functionalized electrospun poly(caprolactone) scaffolds under simulated in vivo environment

Abstract

The difference in the tumor environment from the normal healthy tissue can be therapeutically exploited to develop new strategies for controlled and site-specific drug delivery. In the present study, a continuous flow system is designed to represent the in vivo environment of a tumor tissue and drug release is studied at different pH that represents normal tissue pH, tumor tissue pH, and stomach pH. The results obtained from these experiments were translated to a human embryonic kidney cell culture system and the effect of drug released from these functionalized PCL scaffolds on cell viability was studied. A significant decrease in cell viability was observed with the doxorubicin hydrochloride concentration that would be released at acidic pH, either present as a result of tumor extracellular environment or could be achieved via fabrication of a composite scaffold with a polyvinyl alcohol hydrogel containing acid. In the end, a study using zebrafish as an animal model is also undertaken in order to study the drug release from the scaffolds in vivo.

Keywords:

• Poly(caprolactone)
• functionalization
• pH-controlled delivery
• doxorubicin hydrochloride
• continuous flow
• composite scaffolds
• in vivo study

Acknowledgments

The authors are grateful to Earl Ada for assistance with XPS analysis, and to Chen-Lu Yang for providing support for SEM analysis.