Poly(3-hydroxybutyrate), P3HB, is a biodegradable polymer produced and stored by different bacterial strains, including Ralstonia eutropha H16. P3HB was used to prepare biocompatible composites modified by nanocellulose. This study aimed to assess selected thermal, mechanical, and biological properties of the obtained nanobiocomposites. Thermal properties, as determined by differential scanning calorimetry measurements, were established. The crystallinity of nanocomposites and polymeric matrix was investigated using DSC analyses. The morphology of the nanocomposites was evaluated using scanning electron microscopy. The Food and Drug Administration and the European Medicines Agency confirmed the immunosafety of the tested nanocomposites and noted they had either no or very low levels of endotoxin contamination. Some mechanical properties of the investigated materials were also measured and are presented here. It was estimated that the addition of 1% by mass of nanocrystalline cellulose to P3HB causes the greatest improvement in the plasticization of the material, characterised by the best processing and utility properties. The processing window of nanobiocomposites was extended by approximately 25 °C in reference to the unfilled poly(3-hydroxybutyrate). Mechanical and thermal tests revealed that the most desirable properties oscillate around the addition of 0.5% and 1% nanocrystalline cellulose by mass in the nanobiocomposites. Biological studies on implant applications have shown that the addition of only 0.5% nanofiller to a nanobiocomposite can be of key importance.

Cytisine is a plant-derived quinolizidine alkaloid found, among other sources, in the seeds of the common laburnum (Laburnum anagyroides). It has properties that enable it to act as a partial agonist of brain nicotinic α4β2 receptors, which play a key role in the development and maintenance of nicotine addiction. Clinical studies have shown that cytisine is a more effective smoking cessation aid than nicotine replacement therapy and at least as effective as varenicline in treating tobacco cigarette addiction. It may also be an effective agent in treating addiction to electronic cigarettes. Cytisine is also significantly cheaper than other anti-nicotine medications. This is of great importance for the population of smokers in developing countries, who cannot afford anti-nicotine treatment. In recent years, the role of cytisine in the pharmacotherapy of nicotine addiction worldwide has increased significantly. This drug is becoming available in an increasing number of countries, and in 2025 the World Health Organization (WHO) added cytisine to the list of essential medicines. The need for further development of the drug poses additional challenges for scientists, including the creation of new pharmaceutical forms, optimization of dosing regimens, and expansion of indications to include the treatment of nicotine addiction supplied into the body in forms other than traditional tobacco products. This review describes the use of cytisine in the treatment of nicotine addiction, the drug’s mechanism of action, pharmacokinetics, efficacy, safety of use, and the available pharmaceutical preparations. It also presents research directions on cytisine related to the development of innovative pharmaceutical products, new dosing regimens, and new indications associated with the treatment of addiction to various nicotine-containing products. Conclusions indicate that cytisine has a difficult dosing regimen, which is why patients do not adhere to it, limiting the effectiveness of the therapy. This necessitates optimizing the dosage of existing capsules and tablets or introducing, for example, new extended-release forms of the drug containing cytisine.

Poly(3-hydroxybutyrate) (P3HB) was used to produce biocompatible composites with hypromellose as an additive. The study aimed to assess their biological and mechanical properties, as well as specific thermal parameters and phase content. Differential scanning calorimetry was applied to analyze the phase transitions of both biocomposites and the polymer matrix. Furthermore, the thermal parameters—encompassing both non-equilibrium and equilibrium states—of the biocomposites and unfilled P3HB were evaluated according to their thermal history. Using equilibrium parameters such as the heat of fusion for fully crystalline materials and the heat capacity change at the glass transition for fully amorphous composites, we estimated the degrees of crystallinity as well as the mobile and rigid amorphous fractions. Adding hypromellose to the P3HB matrix reduced crystallinity compared to the unfilled material. At the same time, an increase in the amorphous phase was observed. It was also discovered that the rigid amorphous fraction exists solely in biocomposites containing 2% by mass of filler. Thermogravimetric analysis showed that the thermal stability of all biocomposites surpasses that of unfilled P3HB. Adding an extra 1% filler by mass raises the degradation temperature by about 37 °C compared to unfilled P3HB. The immunosafety of the tested biocomposites, with very low or no endotoxin contamination, was confirmed in accordance with Food and Drug Administration and European Medicines Agency guidelines. The study clearly demonstrates the influence of the filler in the P3HB matrix on various structural, thermal, mechanical, and biological properties of the prepared biocomposites.