The thermal properties of chitosan and hydroxyapatite (HAp)-crosslinked polyurethanes (PU) prepared in a two-step bulk polymerization were investigated. Synthesis of PU was carried out using 1,6-hexamethylene diisocyanate, poly(ethylene glycol) 2000 and dibutyltin dilaurate as a catalyst. Various molar ratios of chitosan and 1,4-butanediol were applied, and the effects of incorporating different HAp amounts and the chitosan-to-BDO ratio were studied. It was found that the thermal properties of PU materials depend on polysaccharides and bioceramics load, which was confirmed by differential scanning calorimetry and thermogravimetry. The glass transition temperature increases with increasing chitosan fraction. Similarly, the onset temperature of degradation increased with chitosan addition. On the other hand, the presence of ceramics did not show a significant impact on the thermal properties of PU composites. Successful polymerization and chain extension of the isocyanate groups with hydroxyl moieties from chitosan and HAp were confirmed by Fourier transform infrared spectroscopy, and the morphology was examined using scanning electron microscopy.

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The diagnosis of affective disorders has been the subject of constant research by clinicians from all over the world for many years. Making an appropriate diagnosis among patients suffering from mood disorders is sometimes problematic due to the personality-changing nature of patients and the similarity in the clinical picture of episodes in affective disorders. For this reason, there is a need to develop rapid and effective methods of determining biological markers that differentiate these diseases. The research was carried out with blood taken from 15 patients and 15 volunteers. The analysis of biological material for trace concentrations of zinc and copper was carried out with the use of ultrasensitive triple-quadrupole inductively coupled plasma mass spectrometry (TQ ICP-MS). The obtained results prove that the concentration of copper in the test group was lower than in the control group. For the zinc concentrations, the inverse relationship was observed. The group of patients was characterized by a higher concentration of this element than the group of healthy volunteers. Summarizing the obtained results and comparing them with the results of studies by other authors, it was found that zinc and copper may be potential biomarkers of affective disorders and pandemic syndrome.