Full Poly(ethylene glycol) Hydrogels with High Ductility and Self-Recoverability

Abstract

Energy dissipation is a common mechanism to improve the ductility of polymeric hydrogels. However, for poly­(ethylene glycol) (PEG) hydrogels, it is not easy to dissipate energy, as polymer chains are dispersed in water without strong interchain interactions or decent entanglement. The brittleness limits the real applications of PEG hydrogels, although they are promising candidates in biomedical fields, as PEG has been approved by the U.S. Food and Drug Administration. Herein, we chemically introduced a center for energy dissipation in the PEG hydrogel system. Amphiphilic segmented PEG derivatives were designed through the melt polycondensation of triethylene glycol (PEG150) and high molecular weight PEG in the presence of succinic acid and mercaptosuccinic acid as dicarboxylic acids. Full PEG hydrogels with elastic nanospheres as giant cross-linkers were facilely prepared by the self-assembly of esterified PEG150 segments and the oxidation of mercapto groups. The resultant full PEG hydrogels can dissipate energy by the deformation of elastic nanospheres with outstanding ductility and self-recoverability while maintaining the excellent biocompatibility owing to their full PEG components. This work provides an original strategy to fabricate full PEG hydrogels with high ductility and self-recoverability, potentially applicable in biomedical fields.

Reduction-Responsive Anticancer Nanodrug Using a Full Poly(ethylene glycol) Carrier

“…This novel mechanism enables efficient polymerization of high-molecular-weight diols with dicarboxylic acids, which is unable to be achieved by the traditional direct polyesterification method. 47 Following a two-step process, PEGs were first esterified with excess MSA (1.5 equiv) to form a carboxyl-terminated prepolymer; then, the molecular chains were continuously propagated by regenerating MSA and subliming it from the polymerization system under a reduced pressure (<100 Pa). Despite strong hydrophilicity of PEG, we found that the polymerization of the two PEGs with MSA significantly influences the aqueous solubility of the polymer.…”

“…Here, we prepared a full-PEG micellar nanodrug with reduction-responsive properties based on an amphiphilic PEG derivative (Figure a), which was synthesized from copolymerization of two PEGs with different molecular weights (i.e., PEG 200 and PEG 10k ) and mercaptosuccinic acid (MSA) via a previously reported carboxyl-ester transesterification (CET) mechanism. , This amphiphilic PEG derivative can spontaneously form micelles with a core–shell structure in the aqueous environment via self-assembly (Figure b). Paclitaxel (PTX) is thereby encapsulated into the micellar core by taking advantage of the hydrophobic interaction between PTX and the hydrophobic segment of the PEG derivative.…”

A Critical Review of Additive Manufacturing Techniques and Associated Biomaterials Used in Bone Tissue Engineering

“…However, it is difficult to disperse energy in PEG hydrogels. Ge et al [ 129 ] investigated solutions to this limitation. In the presence of succinic acid and mercaptosuccinic acid as dicarboxylic acids, PEG derivatives were designed via melt polycondensation of triethylene glycol (PEG (150)) and high-molecular-weight PEG.…”

Effect of Micro-/Nanoparticle Hybrid Hydrogel Platform on the Treatment of Articular Cartilage-Related Diseases

“…Figure 2 shows the variety of micro-/nanoparticles and hydrogels according to their diverse properties. covery of hydrogel [37]. Microparticles are found to make up for the deficiency of hydrogel in mechanical and stable properties.…”

“…A great number of researchers have already focused on this for research into multi-field as well as cartilage-related diseases. Some studies show that nanospheres can enhance lubrication [36], ductility, and self-recovery of hydrogel [37]. Microparticles are found to make up for the deficiency of hydrogel in mechanical and stable properties.…”