Advanced Ceramics Progress
Volume:8 Issue: 4, Autumn 2022

Biomedical engineering has been developed to be applied in repairing/regenerating the damaged tissues or organs to facilitate restoration of the lost biological function. Regenerative medicine has been frequently investigated over years to promote the methodology of the replacement of the injured cells and tissues and improve the life quality of the affected individuals. In this regard, the current study examined the application of various ceramic and metal nanoparticles and polymers in treatment of several tissue/organ damages. It was revealed that application of nanotechnology in tissue regeneration could remarkably improve these approaches and succeed in obtaining low-cost, long-lasting, nanoscale scaffolds to be used in clinical practice where nanomaterial-based tissue regeneration showed greater efficacy than the conventional artificial or animal-derived grafts. In addition, nanomaterials with antibacterial or anti-inflammatory properties may be able to overcome some challenges such as infections, inflammations, and immune responses. With the knowledge of regenerating the damaged tissues using nanomaterials, it is possible to combine the nanomaterials strength or antimicrobial properties with the biological properties, such as tissue-specific growth factors, and create new alternatives that are similar to the original tissues of the human body in terms of their preferred properties and characteristics. Different nanomaterials and their applications in the regeneration of bone, tooth, skin, heart, neurons, and bladder tissues were studied in this review. Despite great promise that these approaches have brought into the replacement of damaged organs, many challenging issues still remain unresolved.

There has been a significant rise in the scientific, technological, ecological, economic, and social popularity of applications of by-products or waste materials in various industries including the agricultural sector. A by-product of rice4 milling is Rice Husk (RH), which, when burned, produces Rice Husk Ash (RHA). RHA is considered an economically viable raw material used for developing silica-based products since it contains a significant amount of amorphous silica (between 85 and 95 percent). The current research aims to create a green process for producing silica powders from RHA, an inexpensive source rich in biocompatible silica. High-purity silica was successfully generated from RHA through alkaline extraction using the reflux technique and subsequent acidification. For this purpose, RH was burned in an electric furnace for five hours to create RHA at 700 °C. The obtained ash was washed with hydrochloric acid to eliminate the metallic impurities. The sodium silicate solution was then obtained by refluxing the acid-washed RHA in a NaOH solution. The final step was to precipitate silica from sodium silicate solution by adding hydrochloric acid to decrease the pH by 4. Characterizations made in general are Thermo-Gravimetric Analysis (TGA), X-Ray Fluorescence (XRF) for identifying the mineral contents of RHA, Fourier-Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM). Simple, efficient, environmentally-friendly, and ideal for mass production are all attributes of the synthetic process.

In this study, the effects of GO-silane particles embedded into the oxide coating during Plasma Electrolytic Oxidation (PEO) of titanium on the growth mechanism, bioactivity, and corrosion properties were investigated. The results revealed that participation of GO-silane particles in titanium oxidation reactions led to the preparation of the oxide coating at higher responding voltages as well as the predominance of rutile over anatase. Introduction of the maximum amount of 5 g.L-1 of GO-silane particles decreased the oxide coating thickness by about 51 % and increased its surface roughness up to around 48 %. The bioactivity of the oxide coating was improved by embedding GO-silane particles and consequently, the amount of induced calcium phosphate compounds increased. Compared to titanium in normal and inflammatory simulated body fluid, pure PEO-treated titanium promoted the polarization resistance and expanded the passivation region. Followed by incorporation of the GO-silane particles into the oxide coating, the protective function was weakened, hence the possibility of tailoring the corrosion properties according to the clinical applications.

In recent years, application of Hydroxyapatite (HA) as the coating on metal substrates for biological stabilization of implants, stimulation of bone growth around the implant, and optimization of recovery time has attracted the attention of many researchers around the world. In this regard, the current study presented a review of HA and its composite coatings for tissue engineering applications. HA is one of the bioceramics that has been an interesting subject of research in recent years owing to its in-vitro bioactivity, osteoinduction, and osteoconduction properties. According to the previous reports, coated implants were performed successfully to achieve high corrosion resistance, bone growth and regeneration, and reduction of corrosion current density. The current research presented a review of the previous research works on the coating mechanism, physico-mechanical, in-vitro bioactivity, and biocompatibility properties of HA and its composite coatings on substrates. The obtained results revealed that HA and its composites had a synergistic effect on the metal substrates in terms of improving corrosion resistance, providing biocompatibility, direct bonding to tissue, accelerating treatment, and reducing costs imposed on the health care sector.

Numerous researchers have shown interest in the new technique of adding various nanoparticles to elastic materials in an attempt to improve their properties. Physical qualities such as wear resistance, strength, thermal properties, tear limit, and elastic fracture were improved as a result of the atomic scale bonds between the nanoparticles and elastic compounds. These characteristics will in turn lead to high-quality and market-friendly products that can compete in international markets. According to the literature, various nanoscale materials including graphene, calcium carbonate (CaCO3) nanoparticles, aluminum nanoparticles, diamond nanoparticles, nanoclays, and zinc oxide nanoparticles have been widely used in the rubber industry. Development of significant CaCO3 nanoparticle structures has continued to date. Carbon nanotubes are another type of nanoscale that can be employed in the rubber industry. In this paper, the effect of graphene on the mechanical properties of rubber compounds was studied due to the significance of incorporation of graphene into the composites, especially into the rubber compounds. The obtained results demonstrated that mechanical properties including tensile strength, wear resistance, and elongation percentage could be easily enhanced by adding graphene to rubber materials. The authors hope that these enhanced compounds will be applicable to the industrial production.

In this research, a new polyurethane / strontium hexaferrite / clinoptilolite (PU/SrM/CLP) nanocomposite was synthesized through the in-situ polymerization method, and its chemical stability in both acidic and alkaline solutions was assessed. It was found that the incorporation of CLP and SrM into the PU matrix would enhance the thermal stability of the nanomaterial. The thermal stability of the composite ingredients against the thermal events up to the temperature of 700 °C in an ascending order includes PU, strontium hexaferrite, and CLP zeolite, respectively. As a result, the formed nanocomposite exhibited more thermal stability than PU. Several analytical techniques such as XRF, XRD, FTIR, SEM-EDX, and BET were employed to characterize the physicochemical properties of the nanocomposite. The presence of FTIR peaks at the wavelengths of 1700 cm-1 and 3400 cm-1 confirms the C=O and N–H groups due to the formation of PU in the composite structure, respectively. The pore volume and specific surface area of the Nano sorbent using BET were obtained as 0.5978 cm3/g and 2.60 m2/g, respectively. Based on the Scherrer equation, the adsorbent crystallite size was measured as 12.76 nm at the highest peak (100 %). In addition, The chemical stability of the prepared nanocomposite was assessed in both acidic and alkaline solutions which showed about a 12 % reduction. The point of zero charge (pHpzc) for nano sorbent was 7.4. According to the obtained results, the PU/SrM/CLP nanocomposite can be utilized as a stable and magnetic sorbent in aqueous harsh media, especially in wastewater samples.