Kazan Federal University

About: Kazan Federal University is a education organization based out in Kazan’, Russia. It is known for research contribution in the topics: Population & Chemistry. The organization has 9868 authors who have published 14390 publications receiving 135726 citations. The organization is also known as: Kazan (Volga region) Federal University & Kazan State University.

3D Printing of Octacalcium Phosphate Bone Substitutes.

Abstract: Biocompatible calcium phosphate ceramic grafts are able of supporting new bone formation in appropriate environment. The major limitation of these materials usage for medical implants is the absence of accessible methods for their patient-specific fabrication. 3D printing methodology is an excellent approach to overcome the limitation supporting effective and fast fabrication of individual complex bone substitutes. Here we proposed a relatively simple route for 3D printing of octacalcium phosphates in complexly shaped structures by the combination of inkjet printing with post-treatment methodology. The printed octacalcium phosphate blocks were further implanted in the developed cranial bone defect followed by histological evaluation. The obtained result confirmed the potential of the developed octacalcium phosphates bone substitutes, which allowed 2.5-time reducing of defect’s diameter at 6.5 months in a region where native bone repair is extremely inefficient.

Examining the Casimir puzzle with an upgraded AFM-based technique and advanced surface cleaning

Abstract: We performed measurements of the gradient of the Casimir force between Au-coated surfaces of a sphere and a plate by means of a significantly upgraded dynamic atomic force microscope (AFM)-based technique. By introducing a combined cleaning procedure of interior surfaces of the vacuum chamber and the test bodies by means of UV light and Ar ions, we reached higher vacuum and eliminated the role of electrostatic patches. Furthermore, the use of a much softer cantilever allowed a sixfold decrease of the systematic error in measuring the force gradient. The experimental data are compared with the theoretical predictions of the Lifshitz theory taking into account corrections due to the inaccuracy of the proximity force approximation and that due to surface roughness. It is shown that the theoretical approach accounting for the relaxation properties of free electrons is excluded by the data up to a larger than previous sphere-plate separation of 820 nm, whereas an alternative approach is found in very good agreement with the data. The importance of these results in connection with the foundations of quantum statistical physics is discussed.

Fluorescence and Cytotoxicity of Cadmium Sulfide Quantum Dots Stabilized on Clay Nanotubes

Abstract: Quantum dots (QD) are widely used for cellular labeling due to enhanced brightness, resistance to photobleaching, and multicolor light emissions. CdS and CdxZn₁-xS nanoparticles with sizes of 6⁻8 nm were synthesized via a ligand assisted technique inside and outside of 50 nm diameter halloysite clay nanotubes (QD were immobilized on the tube's surface). The halloysite⁻QD composites were tested by labeling human skin fibroblasts and prostate cancer cells. In human cell cultures, halloysite⁻QD systems were internalized by living cells, and demonstrated intense and stable fluorescence combined with pronounced nanotube light scattering. The best signal stability was observed for QD that were synthesized externally on the amino-grafted halloysite. The best cell viability was observed for CdxZn₁-xS QD immobilized onto the azine-grafted halloysite. The possibility to use QD clay nanotube core-shell nanoarchitectures for the intracellular labeling was demonstrated. A pronounced scattering and fluorescence by halloysite⁻QD systems allows for their promising usage as markers for biomedical applications.

Bismuth(III) Halide Complexes: New Structural Types and New Application Areas

Abstract: Recent advances in studies of bismuth(III) halide complexes (HBs) are reviewed concisely. New structural types of HBs and some of their physical properties that show the greatest promise for application and attract the greatest attention of researchers are discussed.