Poly(ethylene glycol)‐based hydrogels as cartilage substitutes: Synthesis and mechanical characteristics

Abstract

Cartilage substitutes are needed to replace cartilage tissue, damaged in accidents or by pathologies (e.g., osteoarthritis). Treatment by total hip replacement has disadvantages, particularly due to immunological reaction to the implant's wear debris. One promising alternative is to replace damaged cartilage with substitutes based on hydrogel-type material, designed to mimic the structure and properties of cartilage. The development of such a substitute must consider a wide spectrum of requirements. In this study, we addressed one aspect of this development namely the preparation and investigation of hydrogels exhibiting the required mechanical characteristics. To this aim, poly(ethylene glycol) (PEG) hydrogels and amphiphilic interpenetrating polymer networks (IPNs) of PEG with poly(methyl methacrylate) (PMMA) were prepared and characterized for their mechanical and swelling properties. Twenty-seven types of hydrogels were synthesized, differing in their composition: PEG molecular weight, crosslink density, and PMMA volume fraction. The properties measured were water content, compression modulus, strength, fatigue durability, and poroelastic properties (hydraulic permeability and equilibrium modulus). All were investigated as functions of hydrogel's composition. Results show that lower PEG M w , higher crosslink densities and higher PMMA fraction, all lead to higher modulus and lower water content, and that these properties can be controlled independently by proper choice of ingredients. Introduction of IPN greatly improved the hydrogels' strength. No reduction in the compression modulus resulting from fatigue damage was evident. Poroelastic properties varied nonmonotonously with structural characteristics. Seven types of the hydrogels were found to fit cartilage in their water content, modulus, and poroelastic properties.

Influence of Polystyrene on PDMS IPNs Blend Membrane Performance

“…As ethanol-permselective membranes for the concentration of aqueous ethanol solutions, the PDMS and polytrinlethylsilylpropion (PTMSP) are the most interesting and promising membrane materials for hydrophobic=organophilic separation that has been investigated extensively (2). However, PDMS has poor cohesive property and mechanical strength (5).…”

“…The main field of pervaporation separation is the dehydration of organic compounds using a hydrophilic membrane or for the removal of organic solvents from water using an organophilic membrane (1)(2)(3). Desirable membrane properties, regardless of the separation process are high flux and selectivity, chemical resistance, and durability.…”

Bioprinting of Cartilage

“…The natural materials for cartilage repair include chitosan, hyaluronic acid [25,26], collagen [27], and fibrin hydrogels [28,29]. Also, other synthetic polymers are being used in the field such as poly(ethylene glycol) [31,32], poly(N-isopropylacrylamide) [33,34], polyurethane [35], and poly(vinyl alcohol) [36]. Also, other synthetic polymers are being used in the field such as poly(ethylene glycol) [31,32], poly(N-isopropylacrylamide) [33,34], polyurethane [35], and poly(vinyl alcohol) [36].…”

Mechanically Strong Microstructured Hydrogels Based on Reactive Star‐Shaped Prepolymers

“…This way, for example, poly(ether urethane)/poly(methyl methacrylate) (PEU/PMMA) IPN hydrogels exhibiting significant compression stress-atbreak of 3.5 MPa have been developed. [8] Another strategy is reinforcement with usually nanometer sized fillers, first introduced by Haraguchi et al [9] The properties of such nanocomposite hydrogels (NC) strongly depend on the interfacial interaction between filler and hydrogel which may lead to strong mechanical reinforcement. In their work various types of clay particles were used as a cross linker agent during a free-radical polymerization of N-isopropylacrylamide (NIPA), resulting in a maximum compression strength of 5 MPa.…”