Reinforcement of PVA in a gadolinium-doped 45S5 bioglass-capped chitosan hydrogel with superior magnetic resonance contrast and osteogenic and angiogenic features

Abstract

Multifunctional 45S5 bioglass-incorporated chitosan (CS)–polyvinyl alcohol (PVA) composite hydrogels were developed for applications in osteoporosis. 45S5 bioglass components were cross-linked in CS–PVA hydrogels using a freeze–thaw technique, followed by lyophilization. These hydrogels exhibited favorable surface porosity, mechanical compatibility and hydrophilic features. Moreover, the incorporation of 45S5 bioglass promoted apatite formation in vitro and demonstrated potential for the sustained release of the bone-resorptive alendronate drug. The angiogenic potential of the hydrogel demonstrated by CAM assay displayed its ability to anchor the integration of blood vessels. Moreover, the incorporation of gadolinium (Gd³⁺) in hydrogels induced a paramagnetic response with enhanced longitudinal relaxation and higher signal intensity in magnetic resonance imaging (MRI). Furthermore, cytocompatibility tests on osteoblast-like MG-63 human osteosarcoma cells exhibited excellent cell proliferation, alkaline phosphatase (ALP) expression and mineralization. The overall study demonstrated the potential of the hydrogel as a scaffold for bone tissue remodeling, which offers the salient features of contrast imaging capabilities and drug delivery ability and aids in osteoblast formation with simultaneous regulation of osteoclast proliferation.