A Thixotropic Polyglycerol Sebacate-Based Supramolecular Hydrogel as an Injectable Drug Delivery Matrix.

Hongye Ye,Daniel Wirawan,Cally Owh,Xian Loh,Shan Jiang,Cavin Ng

doi:10.3390/polym8040130

Abstract

We have developed a “self-healing” polyglycerol sebacate—polyethylene glycol methyl ether methacrylate (PGS-PEGMEMA)/α-Cyclodextrin (αCD) hydrogel which could be sheared into a liquid during injection and has the potential to quickly “heal” itself back into gel post-injection. This hydrogel was shown to be biocompatible and biodegradable and therefore appropriate for use in vivo. Furthermore, the storage and loss moduli of the hydrogels could be tuned (by varying the concentration of αCD) between a fraction of a kPa to a few 100 kPa, a range that coincides with the moduli of cells and human soft tissues. This property would allow for this hydrogel to be used in vivo with maximal mechanical compatibility with human soft tissues. In vitro experiments showed that the hydrogel demonstrated a linear mass erosion profile and a biphasic drug (doxorubicin) release profile: Phase I was primarily driven by diffusion and Phase II was driven by hydrogel erosion. The diffusion mechanism was modeled with the First Order equation and the erosion mechanism with the Hopfenberg equation. This established fitting model could be used to predict releases with other drugs and estimate the composition of the hydrogel required to achieve a desired release rate.

Highlights

Hydrogels of various properties is a topic that has been highly researched in the last few decades [1,2,3,4,5,6,7,8,9,10,11,12]
The synthesis of the PGS- of (PGS)-polyethylene glycol methyl ether methacrylate (PEGMEMA) polymers was verified step-wise using NMR which showed that all intermediates of the reaction were successful and purified (Figure 1)
Present in the PGS-PEGMEMA macromolecules, peaks corresponding to PGS were no longer visible in the NMR spectrums of PGS-PEGMEMA 1 and 2

Summary

Introduction

Hydrogels of various properties is a topic that has been highly researched in the last few decades [1,2,3,4,5,6,7,8,9,10,11,12]. Injectable sustained-release drug delivery systems have been well-researched in the past decade, with some progress made, and a number of issues have been raised on the matter. Thermoplastic pastes like polylactic acid (PLA), poly(lactic-co-glycolic acid)(PLGA) and polycaprolactone (PCL)

Methods

Results

Conclusion