Fabrication Of A Bio-inspired Stiff,biocompatible Polyelectrolyte/CaCO₃ Film By Layer-by-layer Method

An ideal biomaterial for biomedical engineering should mimic the intrinsic properties of natural tissue,especially high toughness,in order to withstand cyclic loading and repair skin and muscle damage.In addition,excellent cell affinity and tissue adhesiveness enable integration with the surrounding tissue after implantationOrganic/inorganic bio-inspired nano composites with outstanding mechanical and biochemical properties is extensively studied,although it is challenging to integrate the functional properties such as biocompatibility with mechanical properties for their multi-functional purposes Inspired by nature,we have developed a nanocomposite using polyelectrolytes of polyacrylic acid(PAH),poly(amido amine)(PAMAM)and nano calcium carbonate(nano CaCO3)via a layer-by-layer self-assembly method,with potential applications in biomedical field.The prepared hybrid nanocomposite film was characterized using atomic force microscopy(AFM),scanning electron microscope(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and Raman spectroscopy.In addition,mechanical and functional properties of the composite film were evaluated.Following mineralization,synthesized composite film showed remarkable mechanical properties with an average Young's moduli of 10.6 GPa in comparison with unmineralized composite films with an average Young modulus of 5.2 GPa.Furthermore,the mineralized composite films showed improved piezo electric properties in comparison with the control samples.Cytocompatibility evaluation of the composite material was tested on human lung Fibroblast cells(hLFCs)using the LIVE/DEAD assays,and the results indicated negligible toxicity towards cells.The cells attached and grew onto the composite film and spread after 48 h of incubation.Moreover,drug release through the composite film was examined using a drug model methylene blue(MB),as well as an antibiotic gentamycin sulfate(GS)and the results reveled that the composite film possess sustained drug release properties Owing to improved mechanical properties,excellent biocompatibility,and tunable drug release behavior,the present(PAH/PAMAM)7.5-CaCO3 hybrid nanocomposite film may find broad applications in biomedical fields.