Heikki J Tenhu

Learn More
Thermosensitive polymers poly(N-isopropylacrylamide) (PNIPAM), poly(N-vinylcaprolactam) (PVCL) and PVCL grafted with amphiphilic poly(ethylene oxide) (PEO) chains (PVCL-graft-C11EO42) were prepared and characterized and their putative cytotoxicity was evaluated. The cytotoxicity of these thermosensitive polymers and their monomers was investigated as a(More)
Asymmetrical flow field-flow fractionation (AsFIFFF) was used to determine the hydrodynamic particle sizes, molar masses, and phase transition behaviour of various poly(N-isopropylacrylamide) (PNIPAM) samples synthesised by reversible addition--fragmentation chain transfer (RAFT) and conventional free radical polymerisation processes. The results were(More)
The effect of physical cross-linking was studied on the formation and properties of thermosensitive polymer particles of poly(N-vinylcaprolactam), PVCL, and PVCL grafted with poly(ethylene oxide) macromonomer, PVCL-graft-C(11)EO(42). Loading and release of model drugs into/from the hydrogel particles were evaluated. Thermosensitive particles were stabilized(More)
Although silver nanoparticles (NPs) are increasingly used in various consumer products and produced in industrial scale, information on harmful effects of nanosilver to environmentally relevant organisms is still scarce. This paper studies the adverse effects of silver NPs to two aquatic crustaceans, Daphnia magna and Thamnocephalus platyurus. For that,(More)
This work describes the synthesis of temperature-responsive polystyrene-block-poly(N-isopropylacrylamide)-block-polystyrene triblock copolymers, i.e., PS-b-PNIPAM-b-PS, their self-assembly and phase behavior in bulk, and demonstration of aqueous thermoresponsive membranes. A series of PS-b-PNIPAM-b-PS triblock copolymers were synthesized using reversible(More)
Cell-polymer interactions of thermosensitive poly(N-isopropylacrylamide) (PNIPAM) or poly(N-vinylcaprolactam) (PVCL) coated particles with RAW264.7 macrophages and intestinal Caco-2 cells were evaluated. Nanosized particles were prepared by modifying the surface of fluorescent polystyrene (FPS) particles with the thermosensitive polymer gels or with(More)
Thermally responsive hydrogel nanoparticles composed of self-assembled polystyrene-b-poly(N-isopropylacrylamide)-b-polystyrene block copolymers and fluorescent probe 1-anilinonaphthalene-8-sulfonic acid have been prepared by aerosol flow reactor method. We aimed exploring the relationship of intraparticle morphologies, that were, PS spheres and gyroids(More)
The use of various functionalized polymers as stabilizers to design metal core-organic shell hybrid nanoparticle architectures has attracted increasing interest for different applications. The feature article reviews recent reports published from 2004 to the beginning of 2007 on the synthesis of polymer protected gold nanoparticles (AuNPs), and also(More)
Three model drug substances, the beta-blocking agents nadolol and propranolol and a choline-esterase inhibitor tacrine, were used in order to determine how different drug molecules affect the behavior of thermally responsive polymer nanoparticles composed of poly(N-vinylcaprolactam) (PVCL). Pure PVCL particles in water exist in a swollen state at room(More)
Preparation and characterization of europium(III), terbium(III), samarium(III), and dysprosium(III) polystyrene nanoparticle labels with lanthanide-specific fluorescence properties has been presented. Emulsion copolymerization of styrene and acrylic acid was used to synthesize uniform-sized nanoparticles approximately 45 nm in diameter. Europium(III) and(More)