Purpose: Osteoporosis results in a severe decrease in the life quality of many people worldwide. The latest data shows that the number of osteoporotic fractures is becoming an increasing international health service problem. Therefore, a new kind of controllable treatment methods for osteoporotic fractures is extensively desired. For that reason, we have manufactured and evaluated nanohydroxyapatite (nHAp)-based composite co-doped with iron oxide (IO) nanoparticles. The biomaterial was used as a matrix for the controlled delivery of miR-21-5p and miR-124-3p, which have a proven impact on bone cell metabolism. Methods: The nanocomposite Ca₅(PO₄)₃OH/Fe₃O₄ (later called nHAp/IO) was obtained by the wet chemistry method and functionalised with microRNAs (nHAp/[email protected]/124). Its physicochemical characterization was performed using XRPD, FT-IR, SEM-EDS and HRTEM and SAED methods. The modulatory effect of the composite was tested in vitro using murine pre-osteoblasts MC3T3-E1 and pre-osteoclasts 4B12. Moreover, the anti-inflammatory effects of biomaterial were analysed using a model of LPS-treated murine macrophages RAW 264.7. We have analysed the cells’ viability, mitochondria membrane potential and oxidative stress under magnetic field (MF+) and without (MF-). Moreover, the results were supplemented with RT-qPCR and Western blot assays to evaluate the expression profile for master regulators of bone metabolism. Results: The results indicated pro-osteogenic effects of nHAp/[email protected]/124 composite enhanced by exposure to MF. The enhanced osteogenesis guided by nHAp/[email protected]/124 presence was associated with increased metabolism of progenitor cells and activation of osteogenic markers (Runx-2, Opn, Coll-1). Simultaneously, nanocomposite decreased metabolism and differentiation of pre-osteoclastic 4B12 cells accompanied by reduced expression of CaII and Ctsk. Obtained composite regulated viability of bone progenitor cells and showed immunomodulatory properties inhibiting the expression of inflammatory markers, ie, TNF-α, iNOs or IL-1β, in LPS-stimulated RAW 264.7 cells. Conclusion: We have described for the first time a new concept of osteoporosis treatment based on nHAp/[email protected]/124 application. Obtained results indicated that fabricated nanocomposite might impact proper regeneration of osteoporotic bone, restoring the balance between osteoblasts and osteoclast.

In the present work, nanohydroxyapatites (nHAp) doped with copper and/or zinc ions were investigated for the assessment of its antibacterial activity and biocompatibility. Three forms of material with diverse surfaces were tested: nanopowder in colloidal suspension, galactose hydrogel (3,6-Anhydro-α-l-Galacto-β-d-Galactan) scaffold and pellet. The structural and morphological properties of the obtained biomaterials were comprehensively determined by using: XRPD, FT-IR, SEM-EDS, AAS, XPS and EPR techniques. The antimicrobial active ions, mostly Cu²⁺, were successfully released from the apatite structure despite the material being suspended in the porous galactose hydrogel matrix. The colloidal solutions of nanohydroxyapatites on bacterial viability revealed moderate activity of Cu²⁺-doped materials against Escherichia coli strain and significant activity against Pseudomonas aeruginosa strain. The comparative study of bacterial attachment to the hydrogel and pellet surface indicated that hydrogels were more prone to be colonized by both tested strains. Moreover, an additive of the Cu²⁺ ion modified bacterial attachment and biofilms forming on nHAp:Cu²⁺ and nHAp:Cu²⁺-Zn²⁺ materials. In the case of hydrogels, the biofilms were scattered while these forming on other materials were more clumped. The cytotoxicity evaluation of tested biomaterials showed biocompatible properties of both nanomaterial colloidal solutions as well as galactose hydrogel eluates toward normal mouse osteoblast cell lines (7F2) and human chondrocytes (TC28A2) and osteosarcoma cell line (U2OS). The biocompatibility of tested materials was additionally confirmed by conducting a hemolysis assay which showed full hemocompatibility of nanopowder colloidal solutions and galactose-based materials. Furthermore, unaltered red blood cell morphology was visible after a short and long time of incubation with the obtained biomaterials by using confocal laser scanning microscopy (CLSM). The comparison research provided data of 7F2, TC28 and U2OS cell attachment to the galactose hydrogel surface.

The main aim of our research was to investigate antiadhesive and antibiofilm properties of nanocrystalline apatites doped and co-doped with noble metal ions (Ag⁺, Au⁺, and Pd²⁺) against selected drug-resistant strains of Enterococcus faecalis and Staphylococcus aureus. The materials with the structure of apatite (hydroxyapatite, nHAp; hydroxy-chlor-apatites, OH-Cl-Ap) containing 1 mol% and 2 mol% of dopants and co-dopants were successfully obtained by the wet chemistry method. The majority of them contained an additional phase of metallic nanoparticles, in particular, AuNPs and PdNPs, which was confirmed by the XRPD, FTIR, UV–Vis, and SEM–EDS techniques. Extensive microbiological tests of the nanoapatites were carried out determining their MIC, MBC value, and FICI. The antiadhesive and antibiofilm properties of the tested nanoapatites were determined in detail with the use of fluorescence microscopy and computer image analysis. The results showed that almost all tested nanoapatites strongly inhibit adhesion and biofilm production of the tested bacterial strains. Biomaterials have not shown any significant cytotoxic effect on fibroblasts and even increased their survival when co-incubated with bacterial biofilms. Performed analyses confirmed that the nanoapatites doped and co-doped with noble metal ions are safe and excellent antiadhesive and antibiofilm biomaterials with potential use in the future in medical sectors.

In the present study, nanocrystalline Ca–Sr hydroxyapatites structurally modified with Li ⁺ ions as well as co-doped with Eu ³⁺ ions were prepared as biomaterials showing both regenerative and therapeutic functions.

In response to the demand for new multifunctional materials characterized by high biocompatibility, hydrogel (HG) nanocomposites as a platform for bioactive compound delivery have been developed and fabricated. A specific crosslinking/copolymerization chemistry was used to construct hydrogels with a controlled network organization. The hydrogels were prepared using 3,6-anhydro-α-l-galacto-β-d-galactan (galactose hydrogel) together with resveratrol (trans-3,5,4′-trihydroxystilbene) and calcium hydroxyapatite nanoparticles. The resveratrol was introduced in three different concentrations of 0.1, 0.5, and 1 mM. Nanosized calcium hydroxyapatite was synthesized by a microwave-assisted hydrothermal technique, annealed at 500 °C for 3 h, and introduced at a concentration 10% (m/v). The morphology and structural properties of Ca₁₀(PO₄)₆(OH)₂ and its composite were determined by using XRPD (X-ray powder diffraction) techniques, as well as the absorption and IR (infrared) spectroscopy. The average nanoparticle size was 35 nm. The water affinity, morphology, organic compound release profile, and cytocompatibility of the obtained materials were studied in detail. The designed hydrogels were shown to be materials of biological relevance and of great pharmacological potential as carriers for bioactive compound delivery. Their cytocompatibility was tested using a model of human multipotent stromal cells isolated from adipose tissue (hASCs). The biomaterials increased the proliferative activity and viability of hASCs, as well as reduced markers of oxidative stress. In light of the obtained results, it has been thought that the designed materials meet the requirements of the tissue engineering triad, and may find application in regenerative medicine, especially for personalized therapies.

Purpose: The presented study aimed to investigate the effects of Fe₃O₄ nanoparticles and static magnetic field on osteoblast and osteoclasts’ metabolic activity. Methods: Magnetic nanoparticles were prepared by a wet chemical co-precipitation process and analyzed using X-ray powder diffraction, high-resolution transmission electron microscope (HRTEM), dynamic light scattering (DLS), laser Doppler velocimetry, Raman and the Mössbauer spectroscopy. In vitro experiments were performed using MC3T3, 4B12 and RAW 264.7 cell lines. Cells were cultured in the presence of nanoparticles and with or without exposure to the magnetic field. Proteins were investigated with Western blotting and immunofluorescence and Western blot. Gene expression was analyzed with a quantitative real-time polymerase chain reaction. Results: Obtained particles were in the nano-range (average size around 50 nm) and had a spherical-like morphology. The typical hydrodynamic size was in the range 178– 202 nm and Zeta potential equaled – 9.51 mV. Mössbauer spectrum corresponds to the Fe⁺³ ions in tetrahedral (A) and Fe⁺³ and Fe⁺² ions in octahedral (B) sites of Fe₃O₄. In vitro study revealed cytocompatibility and anti-inflammatory effects of fabricated nanoparticles. Furthermore, it was shown that nanoparticles combined with magnetic field exposure enhance osteogenic differentiation of MC3T3 cells by upregulation of RUNX-2 activity. Under the same experimental condition, nanoparticles and magnetic field decreased osteoclastogenesis of 4B12 by the induction of apoptosis through the mitochondrial-dependent pathway. Conclusion: Fe₃O₄ nanoparticles together with magnetic field can be applied for the fabrication of novel biomaterials for the treatment of bone disorders related to bone loss in which a balance between bone-forming and resorbing cells is disturbed.