Nanocomposite based on hydroxyapatite and boron nitride nanostructures containing collagen and tannic acid ameliorates the mechanical strengthening and tumor therapy

The increase in life expectancy has led to a concerning decline in the body's functional capacity, particularly in bone health, where decreased resistance and increased fracture susceptibility pose significant challenges in orthopedics. While traditional bone grafting methods have drawbacks, synthetic materials, particularly hydroxyapatite (HA), offer promising alternatives due to their biocompatibility and osteoconductive properties. However, HA's mechanical limitations necessitate reinforcement, with boron nitride nanostructures emerging as a particularly effective option, enhancing fracture resistance and combining HA with collagen, further mimicking natural bone composition, offering several benefits. Moreover, crosslinking agents like tannic acid (TA) improve collagen's stability and introduce therapeutic benefits. Therefore, the present work aimed to synthesize an innovative nanocomposite formed by hydroxyapatite, boron nitride nanostructures, collagen, and tannic acid. The nanocomposites obtained were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TGA), elemental analysis of carbon, hydrogen, and nitrogen (CHN), and scanning electron microscopy (SEM). Mechanical tests of Vickers hardness, nanoindentation, tensile, and DMA demonstrated an increase in the mechanical resistance of the nanocomposites, thus corroborating their promising character. A controlled drug release test showed that the system could be used for antibiotic (ciprofloxacin) delivery, further expanding its function. Biological cell viability assays reported that the system is not toxic to healthy cells and is harmful to tumor cells, thus demonstrating the antitumor nature of TA. Therefore, integrating HA, BN nanostructures, collagen, and TA into a multifunctional nanocomposite, a novel approach in orthopedic biomaterial design is offered as a promising solution to address various bone-related challenges.