Search

In this work, we show the in vitro anticancer potential of surgical wires, obtained from zinc (ZnMg0.004) or magnesium (MgCa0.7) alloys by spatial technology comprising casting, extrusion, and final drawing processes. We also present the selective anticancer effects of applied soluble multilayer nanocoatings of zinc and magnesium onto titanium surfaces using the pulse laser deposition method. In the latter, the titanium samples were produced via 3D printing using the selective laser melting method and coated with various combinations of zinc and magnesium layers. For cytotoxicity studies, human dental pulp-derived stem cells (hDPSCs) and human osteosarcoma SaOS-2 cell line were used as representatives of healthy and cancer cells. Cells were examined against the 0.3-3.0 cm 2 /mL material extract ratios obtained from experimental and steel surgical wires, the latter being the current clinical industry standard. The MgCa0.7 alloy wires were approx. 1.5 times more toxic to cancer cells at all examined extract ratios vs. the extracts from steel surgical wires that exhibited comparable toxicity towards healthy and cancer cells. The ZnMg0.004 alloy wires displayed increased toxicity towards cancer cells with decreasing extract ratios. This was also reflected in the increased anticancer effectiveness, calculated based on the viability ratio of healthy cells to cancer cells, from 1.1 to 4.0 times. Healthy cell viability remained at 80-100%, whereas cancer cell survival fluctuated at 20-75%, depending on the extract ratio. Furthermore, the culture of normal or cancer cells on the surface of Zn/Mg-coated titanium allowed us to select combinations of specific coating layers that yielded a comparable anticancer effectiveness to that observed with the experimental wires that ranged between 2 and 3. Overall, this work not only demonstrates the substantial anticancer properties of the studied wires but also indicates that similar anticancer effects can be replicated with appropriate nanocoatings on titanium samples. We believe that this work lays the groundwork for the future potential development of the category of new implants endowed with anticancer properties.

In this work, the biological properties of three-dimensional scaffolds based on a blend of nanohydroxyapatite (nHA), silk fibroin (SF), and chitosan (CTS), were prepared using a lyophilization technique with various weight ratios: 10:45:45, 15:15:70, 15:70:15, 20:40:40, 40:30:30, and 70:15:15 nHA:SF:CTS, respectively. The basic 3D scaffolds were obtained from 5% ( w / w ) chitosan and 5% silk fibroin solutions and then nHA was added. The morphology and physicochemical properties of scaffolds were studied and compared. A biological test was performed to study the growth and osteogenic differentiation of human bone marrow mesenchymal stem cells (hMSCs). It was found that the addition of chitosan increases the resistance properties and extends the degradation time of materials. In vitro studies with human mesenchymal stem cells found a high degree of biotolerance for the materials produced, especially for the 20:40:40 and 15:70:15 (nHa:SF:CTS) ratios. The presence of silk fibroin and the elongated shape of the pores positively influenced the differentiation of cells into osteogenic cells. By taking advantage of the differentiation/proliferation cues offered by individual components, the composites based on the nanohydroxyapatite, silk fibroin, and chitosan scaffold may be suitable for bone tissue engineering, and possibly offer an alternative to the widespread use of collagen materials.

In this work, a poly(L-lactide- co -glycolide) (PLGA)-based composite was enriched with one of the following sol-gel bioactive glasses (SBG) at 50 wt.%: A1-40 mol% SiO 2 , 60 mol% CaO, CaO/SiO 2 ratio of 1.50; S1-80 mol% SiO 2 , 20 mol% CaO, CaO/SiO 2 ratio of 0.25; A2-40 mol% SiO 2 , 54 mol% CaO, 6 mol% P 2 O 5 , CaO/SiO 2 ratio of 1.35; S2-80 mol% SiO 2 ,16 mol% CaO, 4 mol% P 2 O 5 , CaO/SiO 2 ratio of 0.20. The composites and PLGA control sheets were then soaked for 24 h in culture media, and the obtained condition media (CM) were used to treat human bone marrow stromal cells (hBMSCs) for 72 h. All CMs from the composites increased ERK 1/2 activity vs. the control PLGA CM. However, expressions of cell migration-related c-Fos, osteopontin, matrix metalloproteinase-2, C-X-C chemokine receptor type 4, vascular endothelial growth factor, and bone morphogenetic protein 2 were significantly increased only in cells treated with the CM from the A1/PLGA composite. This CM also significantly increased the rate of human BMSC migration but did not affect cell metabolic activity. These results indicate important biological markers that are upregulated by products released from the bioactive composites of a specific chemical composition, which may eventually prompt osteoprogenitor cells to colonize the bioactive material and accelerate the process of tissue regeneration.

Hydrogels based on collagen/β-glucan crosslinked with tannic acid were obtained by neutralization using dialysis. The presence of tannic acid allowed obtaining stable hydrogel materials with better mechanical properties. Tannic acid was released from matrices gradually and not rapidly. The antioxidant properties of the obtained hydrogels increased over the course of their incubation in culture media and were dependent on the concentration of tannic acid in the matrices. The obtained materials influenced dehydrogenase activity and the ATP level of pathogens. Additionally, the materials' extracts improved the HaCaT cells' viability. Therefore, the obtained hydrogels seem to be promising biocompatible materials which display antimicrobial properties.

In this study, hydrogels based on chitosan cross-linked by glyoxal have been investigated for potential medical applications. Hydrogels were loaded with tannic acid at different concentrations. The thermal stability and the polyphenol-releasing rate were determined. For a preliminary assessment of the clinical usefulness of the hydrogels, they were examined for blood compatibility and in the culture of human dental pulp cells (hDPC). The results showed that after immersion in a polyphenol solution, chitosan/glyoxal hydrogels remain nonhemolytic for erythrocytes, and we also did not observe the cytotoxic effect of hydrogels immersed in tannic acid (TA) solutions with different concentration. Tannic acid was successfully released from hydrogels, and its addition improved material thermal stability. Thus, the current findings open the possibility to consider such hydrogels in clinics.

Collagen possesses unique properties, e.g., biocompatibility, biodegradability, and non-toxicity. However, collagen material degrades too quickly and has low mechanical properties. One of the methods of polymers' modification is mixing them to obtain blends. In this study, the influence of β-glucan for collagen material was analyzed. The interaction between the functional groups of the polymer was analyzed by ATR-FTIR (attenuated total reflection-fourier transform infrared) spectroscopy. The influence of β-glucan on mechanical properties was evaluated. The surface properties of materials were assessed using contact angle measurements and the topography of materials was evaluated by AFM (atomic force microscope). The structure of materials was analyzed according to SEM (scanning electron microscopy) pictures. Moreover, the DPPH-free radicals' scavenging ability and biocompatibility against erythrocytes and HaCaT cells were evaluated. Collagen and β-glucan were bound together by a hydrogen bond. β-glucan addition increased the roughness of the surface of the film and resulted in a more rigid character of the materials. A small addition of β-glucan to collagen provided a more hydrophilic character. All the materials could swell in in vitro conditions and showed antioxidant activity. Materials do not cause erythrocyte hemolysis. Finely, our cytotoxicity studies indicated that β-glucan can be safely added at small (10% or less) quantity to collagen matrix, they sufficiently support cell growth, and the degradation products of such matrices may actually provide some beneficial effects to the surrounding cells/tissues.

The aim of this work was to study effect of the type of silica nanoparticles on the properties of nanocomposites for application in the guided bone regeneration (GBR). Two types of nanometric silica particles with different size, morphology and specific surface area (SSA) i.e., high specific surface silica (hss-SiO 2 ) and low specific surface silica (lss-SiO 2 ), were used as nano-fillers for a resorbable polymer matrix: poly(L-lactide-co-D,L-lactide), called PLDLA. It was shown that higher surface specific area and morphology (including pore size distribution) recorded for hss-SiO 2 influences chemical activity of the nanoparticle; in addition, hydroxyl groups appeared on the surface. The nanoparticle with 10 times lower specific surface area (lss-SiO 2 ) characterized lower chemical action. In addition, a lack of hydroxyl groups on the surface obstructed apatite nucleation (reduced zeta potential in comparison to hss-SiO 2 ), where an apatite layer appeared already after 48 h of incubation in the simulated body fluid (SBF), and no significant changes in crystallinity of PLDLA/lss-SiO 2 nanocomposite material in comparison to neat PLDLA foil were observed. The presence and type of inorganic particles in the PLDLA matrix influenced various physicochemical properties such as the wettability, and the roughness parameter note for PLDLA/lss-SiO 2 increased. The results of biological investigation show that the bioactive nanocomposites with hss-SiO 2 may stimulate osteoblast and fibroblast cells'proliferation and secretion of collagen type I. Additionally, both nanocomposites with the nanometric silica inducted differentiation of mesenchymal cells into osteoblasts at a proliferation stage in in vitro conditions. A higher concentration of alkaline phosphatase (ALP) was observed on the material modified with hss-SiO 2 silica.

Sodium alginate and tannic acid are natural compounds that can be mixed with each other. In this study, we propose novel eco-friendly hydrogels for biomedical applications. Thus, we conducted the following assessments including (i) observation of the structure of hydrogels by scanning electron microscope; (ii) bioerosion and the concentration of released tannic acid from subjected material; (iii) dehydrogenase activity assay to determine antibacterial activity of prepared hydrogels; and (iv) blood and cell compatibility. The results showed that hydrogels based on sodium alginate/tannic acid exert a porous structure. The immersion in simulated body fluid (SBF) results in the biomineralization process occurring on their surface while the bioerosion studies revealed that the addition of tannic acid improves hydrogels' stability proportional to its concentration. Besides, tannic acid release concentration depends on the type of hydrogels and the highest amount was noticed for those based on sodium alginate with the content of 30% tannic acid. Antibacterial activity of hydrogels was proven for both Gram-negative and Gram-positive bacteria, the hemolysis rate was below 5% and the viability of the cells was elevated with an increasing amount of tannic acid in hydrogels. Collectively, we assume that obtained materials make the imperative to consider them for biomedical applications.

Spacers, in terms of instruments used in revision surgery for the local treatment of postoperative infection, are usually made of metal rod covered by antibiotic-loaded bone cement. One of the main limitations of this temporary implant is the debonding effect of metal-bone cement interface, leading to aseptic loosening. Material selection, as well as surface treatment, should be evaluated in order to minimize the risk of fraction and improve the implant-cement fixation the appropriate manufacturing. In this study, Ti13Zr13Nb alloys that were prepared by Selective Laser Melting and surface treated were coated with bone cement loaded with either gentamicin or nanosilver, and the effects of such alloy modifications were investigated. The SLM-made specimens of Ti13Zr13Nb were surface treated by sandblasting, etching, or grounding. For each treatment, Scanning Electron Microscope (SEM), contact profilometer, optical tensiometer, and nano-test technique carried out microstructure characterization and surface analysis. The three types of bone cement i.e., pure, containing gentamicin and doped with nanosilver were applied to alloy surfaces and assessed for cement cohesion and its adhesion to the surface by nanoscratch test and pull-off. Next, the inhibition of bacterial growth and cytocompatibility of specimens were investigated by the Bauer-Kirby test and MTS assay respectively. The results of each test were compared to the two control groups, consisting of commercially available Ti13Zr13Nb and untreated SLM-made specimens. The highest adhesion bone cement to the titanium alloy was obtained for specimens with high nanohardness and roughness. However, no explicit relation of adhesion strength with wettability and surface energy of alloy was observed. Sandblasting or etching were the best alloys treatments in terms of the adhesion of either pure or modified bone cements. Antibacterial additives for bone cement affected its properties. Gentamicin and nanosilver allowed for adequate anti-bacterial protection while maintaining the overall biocompatibility of obtained spacers. However, they had different effects on the cement's adhesive capacity or its own cohesion. Furthermore, the addition of silver nanoparticles improved the nanomechanical properties of bone cements. Surface treatment and method of fabrication of titanium affected surface parameters that had a significant impact on cement-titanium fixation.