Modulating the Properties of Poly(glycerol sebacate)-Based Polyurethane Hydrogels Using an Organoclay

Abstract

Elastomeric hydrogels are promising in soft tissue applications due to their biomimetic mechanical and physical behaviors. In this study, we design and synthesize a poly­(glycerol sebacate)-based polyurethane-clay nanocomposite hydrogel system with controllable mechanical, swelling, drug release, and biodegradation behaviors. The polymer-clay nanocomposites are synthesized by in situ polymerization in the presence of a solvent, which facilitates the dispersion of clay within the polymer matrix and their bonding. The nanocomposite hydrogels exhibit higher water swelling ratios in comparison to the neat polymer. The fully swollen hydrogels are capable of enduring complex mechanical deformations such as stretching and knotting, while the tensile moduli of the hydrogels mimic various soft tissues in human body. The mechanical behavior of hydrogels is significantly enhanced by the addition of no more than 3 phr clay, showing higher stiffness, strength, ductility, and toughness. The drug loading and release behavior of the hydrogels is investigated with three model drugs, showing selective drug loading capacity and sustained release, based on the Coulombic interaction between the clay and drug molecules. Biodegradation tests under a simulated body condition reveal a highly tunable degradation rate by the clay content in the nanocomposite hydrogels. Good cytocompatibility by the cell metabolic assay with mouse fibroblasts in vitro is also demonstrated. Finally, three-dimensional microporous foam is manufactured as a proof-of-concept study.

Synthesis of Poly(glycerol butenedioate)─PGB─Unsaturated Polyester toward Biomedical Applications

“…Furthermore, considering glycerol polyesters’ still rising medical potential, − PBG will probably be very attractive for medicinal uses. What is more, in our best knowledge, it is one of the first or even the first unsaturated glycerol polyester which could easily react on the α,β-unsaturated moiety.…”

Clay-Based Nanocomposite Hydrogels for Biomedical Applications: A Review

“…Many other studies have been published on the influence of different types of clay and their effects on the drug-release profiles of diverse hydrogels for different therapies: hydrotalcite clay intercalated with different kind of drugs [99]; influence of laponite exfoliation on the release profile of thermo-sensitive hydrogels [100]; magnetic-dependent drug release due to immobilized Fe 3 O 4 nanoparticles on laponite clays [101]; LDH clay and montmorillonite influence on vitamin B12 release [102] and in artificial gastric fluid (AGF) and artificial intestinal fluid (AIF) [103]; laponite's influence on the sustained controlled release of DOX for cancer therapy in a physiological environment [104]; laponite claypolymer microbeads for anti-inflammatory effect in rats by oral controlled drug delivery of diclofenac sodium [105]; the encapsulation and release behavior of inorganic organoclay MMT-based hydrogels for three different model drugs, and the clay's influence on cytotoxicity and biodegradation rates in different conditions [106]; antimicrobial and pH-responsive nanocomposite hydrogels based on sepiolite clays for the delivery of ceftriaxone sodium antibiotic used in the treatment of infections [107] and preparation of gelatin-based aerogels reinforced with MMT for diltiazem delivery, a drug used to reduce blood pressure [108]. MMT addition to pristine chitosan hydrogel beads enhanced their stability and disintegration performance, improved the swelling behavior, increased ofloxacin entrapment, and promoted a sustainable drug release profile.…”

Bioactive Polyurethane–Poly(ethylene Glycol) Diacrylate Hydrogels for Applications in Tissue Engineering

“…PU hydrogels have advanced, tunable, mechanical properties [24], while maintaining the waterholding capacity of traditional hydrogels [19,25,26]. Furthermore, such materials have been developed for the incorporation of biomolecules for enhanced functionality [27,28]. As a result of their wide range of properties, PU hydrogels have been used in applications such as short-term implants, drug delivery vehicles, and wound dressings [29][30][31][32][33][34].…”