Novel polyester-based thermoplastic elastomers for 3D-printed long-acting drug delivery applications

Ioannis Koutsamanis, Amrit Paudel*, Carolina Patricia Alva Zúñiga, Laura Wiltschko, Martin Spoerk

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


To improve patient compliance and personalised drug delivery, long-acting drug delivery devices (LADDDs), such as implants and inserts, greatly benefit from a customisation in their shape through the emerging 3D-printing technology, since their production usually follows a one-size-fits-most approach. The use of 3D-printing for LADDDs, however, is mainly limited by the shortage of flawlessly 3D-printable, yet biocompatible materials. The present study tackles this issue by introducing a novel, non-biodegradable material, namely a polyester-based thermoplastic elastomer (TPC) – a multi-block copolymer containing alternating semi-crystalline polybutylene terephthalate hard segments and poly-ether-terephthalate amorphous soft segments. Next to a detailed description of the material's 3D-printability by mechanical, rheological and thermal analyses, which was found to be superior to that of conventional polymers (ethylene-vinyl acetates (EVA)), this study establishes the fundamental understandings of the interactions between progesterone (P4) and TPC and drug-releasing properties of TPC for the first time. P4-loaded LADDDs based on TPC, prepared via an elaborated solvent-immersion technique, enable the release of P4 at pharmacologically relevant rates, similar to those of marketed formulations based on EVA and silicones. Additionally, TPC demonstrated an exceptional 3D-printability for a wide selection of implant sizes and complex geometries.

Original languageEnglish
Pages (from-to)290-305
Number of pages16
JournalJournal of Controlled Release
Publication statusPublished - 10 Jul 2021


  • 3D-printing
  • Hot-melt extrusion
  • Implant
  • Non-biodegradable polymer
  • Progesterone
  • Urethra pessary
  • Vaginal drug delivery

ASJC Scopus subject areas

  • Pharmaceutical Science


Dive into the research topics of 'Novel polyester-based thermoplastic elastomers for 3D-printed long-acting drug delivery applications'. Together they form a unique fingerprint.

Cite this