Biomechanically Tunable Nano-Silica/P-HEMA Structural Hydrogels for Bone Scaffolding

Abstract

Innovative tissue engineering biomimetic hydrogels based on hydrophilic polymers have been investigated for their physical and mechanical properties. 5% to 25% by volume loading PHEMA-nanosilica glassy hybrid samples were equilibrated at 37 °C in aqueous physiological isotonic and hypotonic saline solutions (0.15 and 0.05 M NaCl) simulating two limiting possible compositions of physiological extracellular fluids. The glassy and hydrated hybrid materials were characterized by both dynamo-mechanical properties and equilibrium absorptions in the two physiological-like aqueous solutions. The mechanical and morphological modifications occurring in the samples have been described. The 5% volume nanosilica loading hybrid nanocomposite composition showed mechanical characteristics in the dry and hydrated states that were comparable to those of cortical bone and articular cartilage, respectively, and then chosen for further sorption kinetics characterization. Sorption and swelling kinetics were monitored up to equilibrium. Changes in water activities and osmotic pressures in the water-hybrid systems equilibrated at the two limiting solute molarities of the physiological solutions have been related to the observed anomalous sorption modes using the Flory-Huggins interaction parameter approach. The bulk modulus of the dry and glassy PHEMA-5% nanosilica hybrid at 37 °C has been observed to be comparable with the values of the osmotic pressures generated from the sorption of isotonic and hypotonic solutions. The anomalous sorption modes and swelling rates are coherent with the difference between osmotic swelling pressures and hybrid glassy nano-composite bulk modulus: the lower the differences the higher the swelling rate and equilibrium solution uptakes. Bone tissue engineering benefits of the use of tuneable biomimetic scaffold biomaterials that can be “designed” to act as biocompatible and biomechanically active hybrid interfaces are discussed.

News in Bone Modeling for Customized Hybrid Biological Prostheses Development

“…1). A comparison of biological stress and strain distribution in the femoral neck and femoral femur could help to understand the correct design procedures required for the design of new innovative biomimetic prostheses (Abdul-Razzak et al, 2012;Annunziata et al, 2006;2008;Apicella et al, 2010;Davide et al, 2015;Aversa et al, 2009;2016a-o;2017a-c;2019;2020a;2020b;2021;Beaupre and Hayes, 1985;Bonfield et al, 1981;Cameron, 1986;Čepelak et al, 2013;Chen et al, 2012;Cormack and Tilocca 2012;Davis et al, 1991;Schwartz-Dabney and Dechow 2003;Duan et al, 2019;Filmon et al, 2002;Frost, 1964;1990;2004;Gorustovich et al, 2010;Gramanzini et al, 2016;Halpin and Kardos, 1976;Heinemann et al, 2013;Hutmacher, 2000;Hoppe et al, 2011;Hench, 1993;Hench and Polak, 2002;Hench and Thompson, 2010;Huiskes et al, 1987;Julien et al, 2007;Jones and Clare, 2012;Kim et al, 2004;Karageorgiou and Kaplan 2005;Kabra et al, 1991;...…”

Acoustic Applications of a Foamed Geopolymeric-Architected Metamaterial

“…In addition, they have very interesting properties like low shrinkage [19] and bond strength [20] for cement structure repairs, thermal stability [21], chemical and freeze-thaw resistance [21,22], long-term durability [22,23], and potentially reliable use in greener technologies [24] and recyclability [25]. Advanced applications like catalysts, moisture sensors, heat storage, pH regulators, immobilisation of heavy metal, and new ceramic biomaterial are also under study [25][26][27][28][29][30][31][32][33][34]. The polycondensation process flexibility allows the specialisation of ceramic-organic hybrids [32,33] and composite materials [34][35][36][37][38] with specific rheological and viscoelastic and chemo-physical properties [10] such as slurry thixotropy or final glassy geopolymer mechanical properties and biocompatibility for their applications as speciality materials.…”

“…Advanced applications like catalysts, moisture sensors, heat storage, pH regulators, immobilisation of heavy metal, and new ceramic biomaterial are also under study [25][26][27][28][29][30][31][32][33][34]. The polycondensation process flexibility allows the specialisation of ceramic-organic hybrids [32,33] and composite materials [34][35][36][37][38] with specific rheological and viscoelastic and chemo-physical properties [10] such as slurry thixotropy or final glassy geopolymer mechanical properties and biocompatibility for their applications as speciality materials.…”

Bio-Resorption Control and Biological Response of Magnesium Alloy AZ31 Coated with Poly-β-hydroxybutyrate

“…Different approaches, such as alloy composition, surface modification, and conversion coatings, have been proposed to improve and to better control the corrosion kinetics of Magnesium alloys [14,[22][23][24][25][26]. Namely, ion implantation [27][28][29], organic coatings [30][31][32][33], alkali heat treatment, micro-arc oxidation [34][35][36], and polymer coating [37][38][39] have been proposed. Among these, biodegradable polymer coatings have been described to have better performance [40][41][42], even if not yet providing proper coating durability and good biocompatibility.…”