Synthesis and characterization of poly(vinyl alcohol)/chondroitin sulfate composite hydrogels containing strontium‐doped hydroxyapatite as promising biomaterials

Abstract

Novel poly(vinyl alcohol)/chondroitin sulfate (PVA/CS) composite hydrogels containing hydroxyapatite (HA) or Sr‐doped HA (HASr) particles were synthesized by a freeze/thaw method and characterized aiming towards biomedical applications. HA and HASr were synthesized by a wet‐precipitation method and added to the composite hydrogels in fractions up to 15 wt%. Physical–chemical characterizations of particles and hydrogels included scanning electron microscopy, energy‐dispersive spectroscopy, Fourier‐transform infrared spectroscopy, X‐ray diffraction, thermogravimetry, porosity, compressive strength/elastic modulus, swelling degree, and cell viability. Particles were irregular in shape and appeared to have narrow size variation. The thermal behavior of composite hydrogels was altered compared to the control (bare) hydrogel. All hydrogels exhibited high porosity. HA/HASr particles reduced total porosity without reducing pore size. The mechanical strength was improved as the fraction of HA or HASr was increased. HASr particles led to a faster water uptake but did not interfere with the total hydrogel swelling capacity. In cell viability essay, increased cell growth (above 120%) was observed in all groups including the control hydrogel, suggesting a bioactive effect. In conclusion, PVA/CS hydrogels containing HA or HASr particles were successfully synthesized and showed promising morphological, mechanical, and swelling properties, which are particularly required for scaffolding.

Strontium‐loaded hydrogel scaffolds to promote gingival fibroblast function

“…Injectable strontium-releasing alginate hybrid hydrogels can improve bone regeneration without any detrimental systemic effects of released strontium 20 while polyvinyl-alcohol hydrogels loaded with hydroxyapatite or strontium-doped hydroxyapatite also demonstrate good biocompatibility and bioactivity of dental pulp stem cells. 48 No loss of cell viability was observed following direct exposure to the strontium-loaded alginate scaffolds in our study and in fact a bioactive effect of strontium-citrate solution or as scaffoldreleased strontium was observed with increased fibroblast metabolic activity and migration to repair in-vitro wounds. Future preclinical studies are required to investigate biocompatibility and efficacy of our developed scaffolds using more complex in vitro representative model systems and small animal in vivo models.…”

“…Biocompatibility of a dental material is crucial for clinical use and natural polymers such as alginate have high biocompatibility with minimal toxicity or other adverse effects. Injectable strontium‐releasing alginate hybrid hydrogels can improve bone regeneration without any detrimental systemic effects of released strontium 20 while polyvinyl‐alcohol hydrogels loaded with hydroxyapatite or strontium‐doped hydroxyapatite also demonstrate good biocompatibility and bioactivity of dental pulp stem cells 48 . No loss of cell viability was observed following direct exposure to the strontium‐loaded alginate scaffolds in our study and in fact a bioactive effect of strontium‐citrate solution or as scaffold‐released strontium was observed with increased fibroblast metabolic activity and migration to repair in‐vitro wounds.…”

Cannabidiol-loaded microparticles embedded in a porous hydrogel matrix for biomedical applications

“…The CBD-loaded microparticles were embedded in a hydrogel matrix of chondroitin sulfate (CS) and polyvinyl alcohol (PVA). Previously, our group demonstrated that CS/PVA hydrogels have remarkable properties that potentize their use as scaffolds [ 33 ]. The porous structure of these hydrogels offers support for the CBD-loaded microparticles by increasing their handling, which in turn facilitates the application of specific treatment sites.…”

An osteogenic, antibacterial, and anti-inflammatory nanocomposite hydrogel platform to accelerate bone reconstruction

“…Thus, treating inflammation is a key factor to enhance the therapeutic effects and arrest tissue loss. 7,8 For comprehensive care of the bone infection, a local release system needs to be established for the supply of multiple drugs to deal with the anti-inflammatory, anti-bacterial, and tissue-regenerative aspects for the complete management of bone infection.…”

“…The synthetic hydroxyapatite has shown an excellent biocompatible nature, osteoconductive properties, non-immunogenic response, a good adhesive affinity for protein and DNA, induction of osteoblast differentiation, and thus superior bioactivity in bone remodeling. 7,[13][14][15] Recently, our group reported strontium/iron cosubstituted hydroxyapatite (Sr/Fe:HAp) nanomaterials possessing more functionality associated with pristine hydroxyapatite for potential biomedical applications. [16][17][18] Sr/Fe:HAp nanoparticles [Ca 10ÀxÀy Sr x Fe y (PO 4 ) 6 (OH) 2 ] belong to the calcium-deficient apatite family, where strontium and/or iron can replace calcium fractions.…”