Catalytic Aquathermolysis of Heavy Oil with Iron Tris(acetylacetonate): Changes of Heavy Oil Composition and <i>in Situ</i> Formation of Magnetic Nanoparticles

We investigated the influence of catalytic aquathermolysis on the composition changes of Ashal’cha heavy oil. The synergetic effect of organic solvent and an oil-soluble catalyst leads to deep conversion of resins into light components. Composition changes of resins and asphaltenes before and after aquathermolysis were investigated by proton nuclear magnetic resonance (¹H NMR), Fourier transform infrared spectroscopy (FTIR), matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS), and elemental analysis. It was shown that iron­(III) tris­(acetylacetonate) forms magnetic nanoparticles (MNPs) during aquathermolysis of heavy oil without any addition of surfactants. Composition of MNPs was determined as a mixture of hematite, magnetite, and maghemite. It turns out that obtained MNPs possess superparamagnetic properties of single-domain nanoparticles

Interfacing Living Unicellular Algae Cells with Biocompatible Polyelectrolyte-Stabilised Magnetic Nanoparticles

Green algae are a promising platform for the development of biosensors and bioelectronic devices. Here we report a reliable single-step technique for the functionalisation of living unicellular green algae Chlorella pyrenoidosa with biocompatible 15nm superparamagnetic nanoparticles stabilised with poly(allylamine hydrochloride). The magnetised algae cells can be manipulated and immobilised using external permanent magnets. The distribution of the nanoparticles on the cell walls of C. pyrenoidosa was studied by optical and fluorescence microscopy, TEM, SEM and EDX spectroscopy. The viability and the magnetic properties of the magnetised algae are studied in comparison with the native cells. The technique may find a number of potential applications in biotechnology and bioelectronics

Self-assembly of chiral fluorescent nanoparticles based on water-soluble L-tryptophan derivatives of p-tert-butylthiacalix[4]arene

New water-soluble tetra-substituted derivatives of p-tert-butylthiacalix[4]arene containing fragments of L-tryptophan in cone and 1,3-alternate conformations were obtained. It was shown that the resulting compounds form stable, positively charged aggregates of 86–134 nm in diameter in water at a concentration of 1 × 10−4 M as confirmed by dynamic light scattering, scanning electron microscopy and transmission electron microscopy. It was established that these aggregates are fluorescently active and chiral. A distinctive feature of the compounds is the pronounced dependence of their spectral (emission and chiroptical) properties on the polarity of the solvent and the length of the linker between the macrocyclic and fluorophore parts of the molecule

A Direct Technique for Magnetic Functionalization of Living Human Cells

Functionalized living cells are regarded as effective tools in directed cell delivery and tissue engineering. Here we report the facile functionalization of viable isolated HeLa cells with superparamagnetic cationic nanoparticles via a single-step biocompatible process. Nanoparticles are localized on the cellular membranes and do not penetrate into the cytoplasm. The magnetically responsive cells are viable and able to colonize and grow on substrates. Magnetically facilitated microorganization of functionalized cells into viable living clusters is demonstrated. We believe that the technique described here may find a number of potential applications in cell-based therapies and in development of whole-cell biosensors