Ricerc@Sapienza

In recent years it is growing the interest in magnetic nanoparticles as supports for chiral ligands, in order to develop a nanostructured catalytic system which combines advantages of homogeneous and heterogeneous catalysis, that is, simple recovery and high catalytic efficiency [1]. In a previous work our research group has developed the highly efficient ligand L1 in the addition of diethylzinc to aromatic aldehydes [2] (Scheme 1), but our ultimate aim was to achieve an analogous of L1 that could be immobilized on magnetic nanoparticles in order to develop a magnetic recoverable

With the aim to easily recover and reuse the catalyst, an efficient amino alcohol catalyst previously tested in the asymmetric addition of diethylzinc to several aromatic aldehydes has been immobilized on proper functionalized superparamagnetic core−shell magnetite−silica nanoparticles and employed in the Henry reaction in the semi-homogeneous phase. The nanocatalyst exhibits a promising catalytic activity that remains unchanged in the three catalytic cycles performed.

Heterogeneous phase catalysis has attracted scientific community in the last few decades because, supporting chiral catalysts on solid supports, it is possible to easily recover and reuse them for several catalytic cycles. Especially the use of magnetic nanoparticles is highly advantageous, both for their high dispersibility in organic solvents that the simple and non-expensive recovery by magnetic decantation. Our attention has been focused on the modification of known efficient chiral ligands’ structure, in order to let them be anchorable on Fe3O4@SiO2 nanoparticles.

Lipase-immobilized nanomaterials with high activity and stable reusability would have a great impact in different fields. However, developing such materials has proven to be challenging. Herein, polymer (pAcDED)-coated magnetic nanoparticles (MNPs) displaying long alkyl chains, either octyl (C8) or hexadecyl (C16), have been prepared and used for immobilization of Candida rugosa lipase. The aim of the study was to develop magnetic supports able to bind enzyme via interfacial activation thus to stabilized the lipase open conformation.

The work describes the preparation of a new magnetic phase for batch enrichment of phosphopeptides. The material exploits the advantages of magnetic solid phase extraction and couples them with the most employed approach for phosphopeptide enrichment, i.e. Ti4+-IMAC. In order to immobilize Ti4+ ions on the surface of the magnetite nanoparticles, they were first covered by a silica shell and then modified to expose at the surface bromine containing groups.

Magnetic materials in sample preparation for shotgun phosphoproteomics offer several advantages over conventional systems, as the enrichment can be achieved directly in solution, but they still suffer from some drawbacks, due to limited stability and selectivity, which is supposed to be affected by the hydrophilicity of the polymeric supports used for cation immobilization. The paper describes the development of an improved magnetic material with increased stability, thanks to a two-step covering of the magnetic core, for the enrichment of phosphopeptides in biological samples.

Structure and dielectric properties of polymer nanocomposites based on isotactic polypropylene and iron oxide
(Fe3O4) nanoparticles are studied. Distribution of magnetite nanoparticles in a polymer matrix was studied by
scanning electron microscopy (SEM, Carl Zeiss). Dielectric properties of nanocomposites were examined by
means of E7-21 impedance spectrometer in the frequency range of 102–106 Hz and temperature interval of
298–433 K. The frequency and temperature dependences of the dielectric permittivity ε, as well as the

Magnetic nanoparticles with superparamagnetic properties have attracted increased attention for
applications in biomedicine, as they exhibit a strong magnetization only when an external magnetic
field is applied. Magnetoliposomes (MLs) are the combination of liposomes with encapsulated
magnetic nanoparticles. The potential applications of these hybrid nanocarriers have been
increasingly recognized as providing significant biomedical application possibilities. However, it is