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The effect of the BaO addition on the microstructure and structure of the glasses from the K2O–MgO–CaO–Al2O3–SiO2-(BaO) system was investigated in this study. The results were obtained by testing the crystallization capability of the glasses during the fast-firing cycle. Thermal analysis proved a high tendency to crystallize the tested glasses/frits. X-ray analysis showed the presence of diopside and anorthite as the main crystalline phases in all glazes obtained from the tested glasses. Microscopic observations showed that barium oxide introduced in the range of 0.4–2.1 mol% into the examined system strongly influences the number and size of crystalline phases. The introduction of 2.1 mol% BaO into the composition also resulted in crystallization of celsian. The thermal characteristic of the glasses was carried out using differential scanning calorimetry (DSC) and the crystalline phases were determined by X-ray diffractometry. The glaze microstructure was investigated by scanning (SEM) and transmission electron (TEM)microscopy. Additional information on the structure of frits was derived from mid-infrared (MIR) and Raman spectroscopy.

The extracellular matrix (ECM) can be a convenient scaffold used in tissue engineering, regenerative medicine and pharmacy. The synthetic cell matrix should imitate the natural extracellular matrix in both composition and architecture. The study examined fibrous chitosan modified with fragments of human collagen I (10–15 amino acids) mimicking the internal sphere of native protein. The surface of chitosan fibers was modified by physical and chemical methods to obtain polysaccharide-peptide conjugates, which may be considered analogous to the complex of glycosaminoglycans (GAG) and peptides present in the cell matrix. The surface of fibrous chitosan was enriched with fragments of human collagen I, using physicochemical properties (water absorption during electrospraying) and chemical compatibility (activity of amide and peptide groups) during synthesis. The method of modification had an effect on changing the diameter of the fibers and their topography, as assessed by means of a scanning electron microscopy (SEM). The presence of peptides on the surface of the fibers was confirmed by spectroscopic studies (FTIR-ATR and FT Raman). It has been shown that the chemical modification provided a homogeneous distribution of the peptide on the fiber, without changing its morphology as opposed to the physical modification of the fiber, which is visible on the surface in the form of peptide aggregates. The biocompatibility of the materials thus obtained was confirmed during biological studies using MG-63 osteoblast-like cells. Correct morphology observed after 3 days of culture (live-dead test) confirmed the suitability of the substrates for biomedical applications.

Performance of hydroxyapatite material in a living body depends on a number of factors. Stability of hydroxyapatite structure, which is influenced by both, preparation conditions of the starting precursor powders and fabrication method of the implant materials, is an important one. Inappropriate preparation conditions of synthesis, calcination of powder and sintering of formed samples result in dehydroxylation and even in decomposition of HAp which lead to the change in the physicochemical properties of implants. In the work samples of hydroxyapatite ceramics have been obtained by two methods, i.e. by hot pressing and by pressureless sintering in the temperature range of 1150–1300 °C. The materials prepared have been studied using FTIR and XRD in order to identify the dehydroxylation processes and the possible hydroxyapatite decomposition during thermal treatment. The usefulness of both methods in identification of thermal stability of hydroxyapatite was confirmed.

During the production of biomedical hydroxyapatite–zirconia (HAp–ZrO 2 ) composites new phases which determine the biocompatibility of implant materials may occur in the system. These phenomena may be associated both with the phase decomposition of hydroxyapatite itself and the interactions between the matrix material and particles of reinforcing zirconia phase. The work deals with the investigations of phase stability of HAp–ZrO 2 composites at high temperature. The composites studied have been in the form of dense sinters obtained by the hot pressing process.