Issue 10, 2023

Injectable thermoresponsive hydrogels based on (Me)PEG–poly(menthide) amphiphilic block copolymers from bioderived lactone

Abstract

In conjunction with the rise in cancer incidence-mortality and handicaps of conventional poly(ethylene glycol)-based polylactide, poly(lactide-co-glycolide), or poly(ε-caprolactone) (PEG-based PLA, PLGA, or PCL) injectable thermoresponsive hydrogel platforms, formulating novel biomaterials exploiting sustainable resources for local drug release purposes has currently become critical. From this point of view, we synthesized MePEG–poly(menthide) (MePEG–PM) diblock and poly(menthide)–PEG–poly(menthide) (PM–PEG–PM) triblock copolymers through ring-opening polymerization of (−)-menthide (70%), acquired from (−)-menthone, a readily accessible ketone derivative of the natural product (−)-menthol, using MePEG and PEG as initiators and Sn(Oct)2 as a catalyst with high conversions (>97%), narrow molecular weight distributions (1.12–1.22), and monomodal GPC traces. The molecular weights of MePEG–PM diblock and PM–PEG–PM triblock copolymers evaluated by GPC and calculated from 1H NMR were close to the theoretical values and increased linearly with increasing monomer-to-initiator ratios. Structural determination of the copolymers was performed by comprehensive analyses via two-dimensional 1H–1H COSY and 1H–13C HMQC techniques. The critical point in the thermoresponsive phase transition behavior was found to be the length of the PM component, which was meticulously tuned during the synthesis of MePEG–PM and PM–PEG–PM. Specifically, injectable thermoresponsive hydrogels based on these diblock and triblock copolymers prepared with lower (Me)PEG/PM ratios were found to be suitable copolymer formulations for local therapy applications as they showed fluid characteristics (sol form) at around 40–44 °C and turned into a gel form after cooling to body temperature. Moreover, the hydrolytic degradation of block copolymers in PBS at two different pH values (6.5 and 7.4) at 37 °C resulted in very high degradations (>50% at 30 days), indicating quite impressive results considering the copolymers to be used in local drug delivery systems.

Graphical abstract: Injectable thermoresponsive hydrogels based on (Me)PEG–poly(menthide) amphiphilic block copolymers from bioderived lactone

Supplementary files

Article information

Article type
Paper
Submitted
21 nov. 2022
Accepted
12 feb. 2023
First published
13 feb. 2023

Polym. Chem., 2023,14, 1141-1154

Injectable thermoresponsive hydrogels based on (Me)PEG–poly(menthide) amphiphilic block copolymers from bioderived lactone

M. O. Arıcan, T. Koldankaya, S. Mert, H. Çoban, S. Erdoğan and O. Mert, Polym. Chem., 2023, 14, 1141 DOI: 10.1039/D2PY01452A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements