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PEDOT Modified Carbon Paste Microelectrodes for Scanning Electrochemical Microscopy

Only one measuring tip was used in three different modes of operation of the Scanning Electrochemical Microscope (feed-back mode, generation-collection mode, potentiometry) to collect chemical information about copper targets. The tip was formed from 5 and 25 μm diameter conventional platinum microdisk electrode by etching a cavity, then electrochemically depositing poly(3,4-ethylenedioxythiophene) (PEDOT) layer doped with hexacyanoferrate and finally filling with modified carbon paste based Cu2+ sensing layer. The preparation and electrochemical working parameters of this kind of solidcontact microelectrodes are discussed as well as SECM applications for copper detection is reported. (doi: 10.5562/cca1784

Electrografting of mixed organophosphonic monolayers for SI-ATRP of 2-methacryloyloxyethyl phosphorylcholine

International audienceNitinol (NiTi), one of the most important alloys for biomedical applications, is still hampered by its surface nickel inclusions, making it sensitive to pitting corrosion and leading therefore to the release of potentially carcinogenic Ni2+ ions. In this work, we assess the impact of the combination of electrografted mixed self-assembled monolayers (SAMs) on NiTi followed by a polymer coating formed by surface-initiated atom transfer radical polymerization (SI-ATRP). The molecular ratio of 11-(2-bromoisobutyrate)-undecyl-1-phosphonic acid (BUPA) to 11-decylphosphonic acid (C10P) on the electroassisted elaboration of the (BUPA/C10P)-NiTi-SAMs has been optimized. A small amount of BUPA (20%) appears to be the most promising condition, as it provides an efficient corrosion resistance and promotes the SI-ATRP of 2-methacryloyloxyethyl methacrylate (MPC). This confers to the surface hydrophilic properties and corrosion resistance close to those NiTi-SAMs when long polymerization times are used (≥ 6 h)