Bioapatite made from chicken femur bone

Nano-bioapatite (BAP) powder was successfully acquired from chicken femur bones via chemical treatment followed by calcination. The isolation of nano-bioapatite powder from chicken bone has not been published so far. The bioapatite powder was chemically and structurally characterized by elemental analysis (AAS), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR) techniques. The nano BAP powder showed needle-shaped morphology. The crystallite size distribution and specific surface area proved the nanostructured character of the sample. Chemical analysis together with FTIR spectrometry have demonstrated that the BAP powder was Ca-deficient with Na, Mg and carbonate substitutions that make the BAP suitable for application as a filler in biocomposites.Web of Science55426025

MECHANICAL AND STRUCTURAL PROPERTIES OF COLLAGEN NANOFRIBROUS LAYERS UNDER SIMULATED BODY CONDITIONS

The theme of this paper is the analysis of mechanical and structural properties of nanofibrous COL under simulated body conditions and in the presence of osteoblasts and dermal fibroblasts. COL were prepared by electrostatic spinning of 8wt% collagen type I dispersion with 8wt% (to COL) of PEG in phosphate buffer/ethanol solution (1/1vol). The stability of COL was enhanced by means of cross-linking with EDC and NHS at a molar ratio of 4:1. COL were exposed in culture medium for 21 days and human SAOS-2 human dermal fibroblasts and osteoblasts were cultured therein for 21 days as well. The cell culture on COL was assessed by fluorescence microscopy and metabolic activity. Then the metabolic activity of both cell types grown on COL and PS were measured after 1, 7, 14 and 21 days using the Alamar Blue assay method. Mechanical properties were determined using an tensile test. The influence of the cell activity on secondary structure of COL was verified by IR spectroscopy. Furthermore, the influence of cells on COL was evaluated by SEM

Various simulated body fluids lead to significant differences in collagen tissue engineering scaffolds

This study aims to point out the main drawback with respect to the design of simulated body environments. Three media commonly used for the simulation of the identical body environment were selected, i.e., Kokubo's simulated body fluid that simulates the inorganic component of human blood plasma, human blood plasma, and phosphate buffer saline. A comparison was performed of the effects of the media on collagen scaffolds. The mechanical and structural effects of the media were determined via the application of compression mechanical tests, the determination of mass loss, and image and micro-CT analyses. The adsorption of various components from the media was characterized employing energy-dispersive spectrometry. The phase composition of the materials before and after exposure was determined using X-ray diffraction. Infrared spectroscopy was employed for the interpretation of changes in the collagen secondary structure. Major differences in terms of the mechanical properties and mass loss were observed between the three media. Conversely, only minor structural changes were detected. Since no general recommendation exists for selecting the simulated body environment, it is necessary to avoid the simplification of the results and, ideally, to utilize alternative methods to describe the various aspects of degradation processes that occur in the media.Web of Science1416art. no. 438

Calcium Orthophosphate–Clay Composites—Preparation, Characterisation, and Applications: A Review

Calcium orthophosphates and clays and their composites are one of the most important groups in the field of new, modern, and technologically advanced materials that are accessible, inexpensive, and environmentally friendly. This review provides a summary of recent research on calcium orthophosphate–clay composites, their preparation, characterisation, and use in various applications. An introduction to the subject is followed by a detailed description of the chemical and physical properties of calcium orthophosphates, clays, and clay minerals. This is followed by a general summary of preparation methods for calcium orthophosphate–clay composites. Particular attention is paid to the description of individual applications, i.e., environmental applications, biomaterials science (tissue engineering, pharmacology), and other emerging applications. Finally, future perspectives are summarised and discussed

Biologicky inspirované nanokompozitní struktury s želatinovými nanovlákny pro regeneraci kostní tkáně

The aims of this work has been the preparation of bioinspired composite materials composed of gelatin matrix, gelatin nanofibers and hydroxyapaptite powder and verifying the influence of nanofibers on the mechanical properties of the composites

Filamentous carbon catalytic deposition of coal-tar pitch fraction on corundum

Our work was focused on deposition of volatile hydrocarbons of carbonaceous precursor on corundum wafer, taking advantage of a metallic catalyst incorporated in precursor. Coal tar-pitch, namely a fraction soluble in toluene, served as precursor material for deposition of filamentous material. The toluene-soluble fraction of tar-pitch originally contained metallic particles of iron and nickel. During heat treatment up to 1000°C, metallic particles accompanied the volatile hydrocarbons conducive to forming a filamentous deposit. The deposit obtained demonstrates a semicrystalline material that has an irregular filamentous structure with an average filament diameter of 30 µm. The presence of catalysts after the deposition process was proved in the deposit but catalysts were not found in the residuum

Effect of nanofillers dispersion in polymer matrices: a review

Science of Advanced Materials (SAM) is an interdisciplinary peer-reviewed journal consolidating research activities in all aspects of advanced materials in the fields of science, engineering and medicine into a single and unique reference source. SAM provides the means for materials scientists, chemists, physicists, biologists, engineers, ceramicists, metallurgists, theoreticians and technocrats to publish original research articles as reviews with author's photo and short biography, full research articles and communications of important new scientific and technological findings, encompassing the fundamental and applied research in all latest aspects of advanced materials

Preparation of Mg-vermiculite nanoparticles using potassium persulfate treatment

Delamination/exfoliation process of the Mg-vermiculite (Letovice, Czech Republic), particles with size less than 5 μm, was studied after potassium persulfate treatment and compared with known method utilized hydrogen peroxide treatment. X-ray powder diffraction (XRPD) patterns showed that treatment of Mg-vermiculite with different molar concentration of potassium persulfate: c = 0 02, 0.04, and 0.08 mol · dm−3 at the temperature 60 °C for 2 hr caused reduction of relative intensity (Irel.) of the basal 001 diffraction to the 15%, 9%, and 4%, respectively, compared to intensity of 001 diffraction of untreated Mg-vermiculite (Irel. = 100%). On the other hand Irel. of the 001 diffraction of Mg-vermiculite after treatment with 30% and 50% (c = 9.8 and 17.4 mol · dm−3) hydrogen peroxide at the 60 °C for 2 hr decreased only to Irel. = 36% and 32%, respectively. Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) verified effect of potassium persulfate treatment on structure degradation which is connected with higher degree of delamination/exfoliation of the particles and their cracking into nano-sized particles

Phase Transformations in Fly Ash-Based Solids

The presented article describes the phase transformations in solid bodies based on fluid fly ash (FFA) over eight years from the initial to the final phases. FFA has been selected as a type of industrial waste whose amount has been growing in recent years. This type of ash has self-hardening properties when watered because of the conditions of its origin. The specific temperature of fluid burning and the addition of calcium carbonate into the burning zone create a mixture of phases which are, even when solidified, ready to form new crystal phases, especially alumina-silicates, relicts of coal clay minerals. For experiments, bricks from the mixture of FFA and quartz sand were industrially produced and left outside. Subsequent mineralogical analyses of samples of various ages confirmed differences in phase compositions. It is supposed that the main role in the presented changes is played by the content of the roentgen-amorphous part of alumina-silicates because they are likely to be transformed into a stable form of feldspar. In addition to that, this article presents the hypothesis of a moving agent, which could explain the transformations in the final bodies