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Uniformly sized magnetite nanoparticles (Dn = 16 nm) were prepared by a thermal decomposition of Fe(III) oleate in octadec-1-ene and stabilized by oleic acid. The particles were coated with Sipomer PAM-200 containing both phosphate and methacrylic groups available for the attachment to the iron oxide and at the same time enabling (co)polymerization of 2-(dimethylamino)ethyl methacrylate and/or 2-tert-butylaminoethyl methacrylate at two molar ratios. The poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA) and poly[2-(dimethylamino)ethyl methacrylate-co-2-tert-butylaminoethyl methacrylate] [P(DMAEMA-TBAEMA)] polymers and the particles were characterized by 1H NMR spectroscopy, size-exclusion chromatography, transmission electron microscopy, dynamic light scattering, thermogravimetric analysis, magnetometry, and ATR FTIR and atomic absorption spectroscopy. The antimicrobial effect of cationic polymer-coated magnetite nanoparticles tested on both Escherichia coli and Staphylococcus aureus bacteria was found to be time- and dose-responsive. The P(DMAEMA-TBAEMA)-coated magnetite particles possessed superior biocidal properties compared to those of P(DMAEMA)-coated one.

Catalytic performance of Se-containing organic substances, namely methylseleninic acid, benzeneseleninic acid, phenylselenol and diphenyldiselenide, has been tested as potential catalysts for unsaturated aldehydes oxidation by hydrogen peroxide. All tested substances proved to be active in the acrolein oxidation reaction but showed different efficiency regarding used solvents and the products of reaction-acrylic acid or methyl acrylate. Optimal catalyst, reaction conditions and solvent for acrylic acid synthesis have been determined.

Star-shaped porphyrin-PNIPAM 4 (PP) conjugates having four PNIPAM arms connected to a central tetraphenylporphyrin unit were synthesized using reversible addition−fragmentation chain-transfer polymerization. Temperature-induced phaseseparation behavior of the conjugates was investigated, and the lower critical solution temperature (type II)−composition phase diagram was constructed using Flory−Huggins theory. Interestingly, in contrast to PNIPAM homopolymers, the shorter PNIPAM arms of PP conjugates lead to a lower phase-separation temperature (T p ). The concentration dependency of the size of the cooperative domain was also determined. Below T p , experimental data indicate that PP behaves as a 1D supramolecular polymer with a concentration-dependent length, while above T p , PP globules adopt a larger spherical shape. Various temperature− pH reversible and irreversible interdependencies ("cross-effects") between phase separation and protonation were observed. The PP conjugates represent a dual temperature−pH-responsive model system possessing various aggregated states, making them candidates for visual indicators, pH or temperature sensors, or singlet oxygen generators for biomedical applications.