Development of advanced nanosized molecularly inprinted polymers via surface-initiatied 'living' radical polymerisation

Surface-initiated photo-iniferter mediated controlled polymerisation was used as a technique for the development of advanced and smart materials. Molecularly imprinted polymer (MIP) shell nanoparticles (NPs) were synthesised in this way from PAMAM dendrimers, used as a graftable core, in 2 min irradiation time. Surprisingly the so-synthetised NPs were around 200 nm and had a cubic shape. Cont/d

Development of label-free impedimetric platform based on new conductive polyaniline polymer and three-dimensional interdigitated electrode array for biosensor applications,

Novel label-free impedimetric platform based on a three-dimensional interdigitated electrode array (3D-IDEA) sensor and new conductive polymer as a transducer for oxidoreductases is introduced. This platform is cost-effective, simple to construct and miniaturize. Monomer of conductive polymer N-(N’,N’-diethyldithiocarbamoylethylamidoethyl) aniline (AnD) was deposited onto 3D-IDEA by chemical polymerisation. It was found that the polymer film resistance depends on the redox-potential of the solution. For the first time polyAnD was used as enzyme immobilisation matrix. Pyrroloquinolinequinone (PQQ) dependent alcohol and glucose dehydrogenases were immobilized on 3D-IDEA covered with polyAnD by two different methods. 3D-IDEA sensors with enzymes, which were immobilised by physisorption on polyAnD layer, showed specific response in the presence of 1 μM of the corresponding substrates. Obtained results revealed that PQQ dependent dehydrogenases can re-oxidize on polyAnD via direct electron transfer (DET) from enzyme active site to the polymer surface. This process can be monitored by methods of electrochemical impedance spectroscopy (EIS) and chronoamperometry. Presented study shows that EIS method gives a useful tool for research of re-oxidation process and interaction of electroactive enzymes with conducting materials giving information required to construct and develop analytical devices.N. Abramova and A. Bratov acknowledge financial support from Spanish Ministry of Science and Innovation (projects AGL2008-05578-C05-05/01; IPT-2011-1055-900000 and CTQ2011-29163-C03-02). E. Voitechovic would like to acknowledge the financial support from St. Petersburg State University PostDoc Grant #12.50.1191.2014 and PhD Student Research Traineeship from the Lithuanian Science Council.Peer reviewe

Conjugated Polymers with Pendant Iniferter Units: Versatile Materials for Grafting

A novel compound N-(N',N'-diethyldithiocarbamoylethylamidoethyl)aniline (NDDEAEA) was synthesized and fully characterized. Conjugated poly(NDDEAEA), consisting of N-substituted polyaniline (PANI) backbones with dithiocarbamate ester pendant groups (which can act as iniferters), was synthesized by both chemical and electrochemical polymerization. UV-initiated living polymerization was utilized to graft styrene, methacrylic acid (MAA), lauryl methacrylate, and acrylamido-2-methylpropanesulfonic acid (AMPSA) onto the conjugated macroiniferter which had previously been deposited on various surfaces (glass, polypropylene, polystyrene, and gold electrodes). The resultant polymeric surfaces were characterized by static contact angle measurements, XPS, SEM, and AFM. This versatile new material can be used for creating materials with integrated functionalities (e.g., conductivity, molecular recognition, catalysis and controlled transport properties, etc.) for application in sensors and microfluidic devices and for the construction of patterned surfaces.</p

Synthesis and Structural Characterization of Group 4 Metal Alkoxide Complexes of <i>N</i>,<i>N</i>,<i>N</i>′<i>,N</i>′‑Tetrakis(2-hydroxyethyl)ethylenediamine and Their Use As Initiators in the Ring-Opening Polymerization (ROP) of <i>rac</i>-Lactide under Industrially Relevant Conditions

A series of <i>N</i>,<i>N</i>,<i>N</i>′,<i>N</i>′-tetrakis­(2-hydroxyethyl)­ethylenediamine (TOEEDH₄) ligand precursors and their group 4 metal complexes have been prepared. The complexes have been characterized by single-crystal X-ray diffraction and ¹H NMR spectroscopy, highlighting the ability to systematically vary the number of TOEED ligands within the system. Initial catalytic data for the solvent-free, ring-opening polymerization of <i>rac</i>-lactide (<i>rac</i>-LA), a promising degradable polymer produced from renewable resources, is reported. At 135 °C, it has been demonstrated that the activity of the complexes is enhanced by increasing the number of labile isopropoxide groups. When the temperature was further increased to 165 °C, all complexes demonstrated a far higher activity irrespective of the identity of the metal or number of labile initiator groups. Polymerization kinetics were monitored in real time using FT-IR spectroscopy with a diamond composite insertion probe and Ti₄(TOEED)­(OⁱPr)₁₂ was demonstrated to convert over 95% of the <i>rac</i>-LA within 160 min

Synthesis and Structural Characterization of Group 4 Metal Alkoxide Complexes of <i>N</i>,<i>N</i>,<i>N</i>′<i>,N</i>′‑Tetrakis(2-hydroxyethyl)ethylenediamine and Their Use As Initiators in the Ring-Opening Polymerization (ROP) of <i>rac</i>-Lactide under Industrially Relevant Conditions

A series of <i>N</i>,<i>N</i>,<i>N</i>′,<i>N</i>′-tetrakis­(2-hydroxyethyl)­ethylenediamine (TOEEDH₄) ligand precursors and their group 4 metal complexes have been prepared. The complexes have been characterized by single-crystal X-ray diffraction and ¹H NMR spectroscopy, highlighting the ability to systematically vary the number of TOEED ligands within the system. Initial catalytic data for the solvent-free, ring-opening polymerization of <i>rac</i>-lactide (<i>rac</i>-LA), a promising degradable polymer produced from renewable resources, is reported. At 135 °C, it has been demonstrated that the activity of the complexes is enhanced by increasing the number of labile isopropoxide groups. When the temperature was further increased to 165 °C, all complexes demonstrated a far higher activity irrespective of the identity of the metal or number of labile initiator groups. Polymerization kinetics were monitored in real time using FT-IR spectroscopy with a diamond composite insertion probe and Ti₄(TOEED)­(OⁱPr)₁₂ was demonstrated to convert over 95% of the <i>rac</i>-LA within 160 min