Transition Metals (Cr3+) and Lanthanides (Eu3+) in Inorganic Glasses with Extremely Different Glass-Formers B2O3 and GeO2

Glasses containing two different network-forming components and doped with optically active ions exhibit interesting properties. In this work, glass systems based on germanium dioxide and boron trioxide singly doped with lanthanides (Eu3+) and transition metals (Cr3+) ions are research subjects. Optical spectroscopy was the major research tool used to record excitation and emission spectra in a wide spectral range for studied systems. The emitted radiation of glasses doped with Cr3+ ions is dominated by broadband luminescence centered at 770 nm and 1050 nm (4T2 → 4A2). Interestingly, the increase of concentration of one of the oxides contributed to the detectable changes of the R-line (2E → 4A2) of Cr3+ ions. Moreover, EPR spectroscopy confirmed the paramagnetic properties of the obtained glasses. The influence of molar ratio GeO2:B2O3 on spectroscopic properties for Eu3+ ions is discussed. The intensity of luminescence bands due to transitions of trivalent europium ions as well as the ratio R/O decrease with the increase of B2O3. On the other hand, the increase in concentration B2O3 influences the increasing tendency of luminescence lifetimes for the 5D0 state of Eu3+ ions. The results will contribute to a better understanding of the role of the glass host and thus the prospects for new optical materials.

Creation of an MRI phantom based on super-paramagnetic nanoparticles of iron oxide (SPIO) for standardization of the conversion of T2 * values in the concentration of iron in the liver

In this study the standardization method for T2* maps acquisition on various MR scanners (3T and 1.5T) is proposed. The reproducibility of the obtained T2* values is realized through the MR-compatible phantom containing paramagnetic complex iron oxide nanoparticles. The repeatability of measurements results has shown that the created phantom retains all the required characteristics (homogeneity, stability of concentrations and manifested paramagnetic properties) over a long period of time. The application of standardized T2* values allows to use previously received T2*, [ms] to iron concentrations in the dry substance of the liver (LIC), [mg/ml] conversion formulas for accurate, fast and non-invasive MRI diagnostics of liver iron overload.

Sol-gel synthesis, crystal structure and magnetic properties of nanocrystalline praseodymium orthoferrite

In this work, nano-sized crystalline praseodymium orthoferrite was successfully synthesized via sol-gel method using water – methanol co-solvent. Single-phase PrFeO3 nanoparticles were formed after annealing the precursors at 650, 750, 850, and 950 °C during 60 min. The crystal size, lattice volume and coercivity (Hc) of nanocrystalline PrFeO3 increase with the annealing temperature. The obtained praseodymium orthoferrite exhibited paramagnetic properties with Hc = 28 – 34 Oe

TMek: UN MICROCHIP PER DIAGNOSTICARE LA MALARIA IN MODO QUANTITATIVO E RAPIDO

Despite the huge efforts for malaria eradication, this infectious disease still represents a critical issue worldwide, with 3.5 billion people still at risk, 229 million new cases and 409.000 deaths in 2019. The infection is caused by the Plasmodiun parasite which attacks red blood cells, feeds on hemoglobin and transform it into hemozoin nanocrystals. In this paper we report on a novel pan-malaria test (TMek), based on the paramagnetic properties of hemozoin nanocrystals, which allows for the automatic quantification of infected red blood cells (i-RBCs) on a microchip. Exploiting the competition between gravity and magnetic forces, i-RBCs in a whole blood specimen are captured on micromagnetic concentrators and electrically detected, allowing for the measurement of their concentration with a limit of sensitivity down to 10 parasites/μl.