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Poly(ethylene glycol)–poly(vinylphosphonic acid) double hydrophilic block copolymers were synthesized by RAFT/MADIX polymerization and used to prepare stable iron oxide nanoparticles.

Superparamagnetic iron oxide nanoparticles (SPIONs) and their derivatives (aminosilane and gold-coated) have been widely investigated in numerous medical applications, including their potential to act as antibacterial drug carriers that may penetrate into bacteria cells and biofilm mass. Pseudomonas aeruginosa is a frequent cause of infection in hospitalized patients, and significant numbers of currently isolated clinical strains are resistant to standard antibiotic therapy. Here we describe the impact of three types of SPIONs on the growth of P. aeruginosa during long-term bacterial culture. Their size, structure, and physicochemical properties were determined using transmission electron microscopy, X-ray diffraction analysis, and Fourier transform infrared spectroscopy. We observed significant inhibition of P. aeruginosa growth in bacterial cultures continued over 96 hours in the presence of gold-functionalized nanoparticles (Fe 3 O 4 @Au). At the 48-hour time point, growth of P. aeruginosa , as assessed by the number of colonies grown from treated samples, showed the highest inhibition (decreased by 40%). These data provide strong evidence that Fe 3 O 4 @Au can dramatically reduce growth of P. aeruginosa and provide a platform for further study of the antibacterial activity of this nanomaterial.

Synthesis of magnetically separable imidazolinium salts (Nheterocyclic carbene precursor) from amine-terminated magnetic nanoparticles by a direct "grafting from" three-step approach was achieved. Purification after each step of the synthesis was easily performed using magnetic separation of products from the reaction mixtures. Next, the magnetic imidazolinium salts were used as ligands in transition-metal complexes. The catalytic properties of nanoparticles−Pd complexes in the Heck cross-coupling reaction were tested. In the majority of tested reactions, the catalyst allowed obtaining styrene derivatives in high yields. It was proven that the catalysts can be reused several times without loss of their activity.

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