Modifying scaffolds with agents that at the same time positively influence osteogenic cells and have a negative impact on cancerous growth, is a promising solution for patients with bone tissue defects following tumor excision. Such materials may not only boost tissue regeneration but also limit the risk of cancer reoccurrence. In our study, we developed novel bifunctional scaffolds containing magnetic nanoparticles grafted with PCL (MNP@PCL) and tannic acid (TA), which may be directed to support normal bone cells and suppress osteosarcoma cells. First, MNPs were postsynthetically surface-modified, by grafting poly(ε-caprolactone) (PCL) from the surface via ring opening polymerization of ε-caprolactone, to provide their uniform distribution within the polymer matrix. Then, fiber mats containing a fixed amount of MNPs (2 wt %) and increasing content of TA (0, 1, 5, and 10 wt %) were prepared by electrospinning method. Both MNP@PCL and TA decreased polymer crystallinity. The interaction between the MNPs and TA significantly influenced the mat morphology, thermal properties, and initial hydrolytic performance. The most intensive TA release was observed mainly within first 6 h of incubation, and it was 3.5-fold higher (ca. 0.02 mg of TA/per mg of mat) for mfPCL@TA-10 compared to mfPCL@TA-5. Moreover, TA-containing magnetic mats suppressed the metabolic activity of osteosarcoma cells. They also demonstrated enhanced antimicrobial properties against the bacteria typically accompanying orthopedic complications, reducing the population of Gram-positive bacteria by more than 90% compared to the neat PCL mat. This proves the high potential of these materials for combining cancer treatment with bone tissue engineering.

• Keywords
• antibacterial, bone regeneration, fiber scaffolds, magnetic nanoparticles, nanocomposites, tannic acid,
• MeSH
• Anti-Bacterial Agents * pharmacology   chemistry   MeSH
• Bone and Bones drug effects   MeSH
• Humans MeSH
• Magnetite Nanoparticles * chemistry   MeSH
• Cell Line, Tumor MeSH
• Bone Neoplasms * drug therapy   pathology   MeSH
• Osteosarcoma * drug therapy   pathology   MeSH
• Polyesters * chemistry   MeSH
• Antineoplastic Agents * pharmacology   chemistry   MeSH
• Tannins * chemistry   pharmacology   MeSH
• Tissue Engineering * methods   MeSH
• Tissue Scaffolds chemistry   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Anti-Bacterial Agents * MeSH
• Magnetite Nanoparticles * MeSH
• polycaprolactone MeSH Browser
• Polyesters * MeSH
• Polyphenols MeSH
• Antineoplastic Agents * MeSH
• Tannins * MeSH
• tannic acid MeSH Browser

Magnetic γ-Fe2O3/CeOx nanoparticles were obtained by basic coprecipitation/oxidation of iron chlorides with hydrogen peroxide, followed by precipitation of Ce(NO3)3 with ammonia. The appearance of CeOx on the magnetic particle surface was confirmed by X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), and elemental analysis; a magnetometer was used to measure the magnetic properties of γ-Fe2O3/CeOx. The relatively high saturation magnetization of the particles (41.1 A·m2/kg) enabled magnetic separation. The surface of γ-Fe2O3/CeOx particles was functionalized with PEG-neridronate of two different molecular weights to ensure colloidal stability and biocompatibility. The ability of the particles to affect oxidative stress in hereditary hypertriglyceridemic (HHTg) rats was tested by biological assay of the liver, kidney cortex, and brain tissues. An improvement was observed in both enzymatic [superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx)] and non-enzymatic (reduced (GSH) and oxidized (GSSG) glutathione) levels of antioxidant defense and lipid peroxidation parameters [4-hydroxynonenal (4-HNE) and malondialdehyde (MDA)]. The results corresponded with chemical determination of antioxidant activity based on 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, proving that in the animal model γ-Fe2O3/CeOx@PEG2,000 nanoparticles effectively scavenged radicals due to the presence of cerium oxide, in turn decreasing oxidative stress. These particles may therefore have the potential to reduce disorders associated with oxidative stress and inflammation.

• Keywords
• antioxidant, cerium oxide, maghemite, nanoparticles, oxidative stress,
• Publication type
• Journal Article MeSH