Sequential In-Situ Growth of Layered Conjugated Polymers for Optoelectronics Under Electrochemical Control.

Layered optoelectronic devices are manufactured using multistep procedures that require high precision in the spatial positioning of individual materials. Current technology uses costly and tedious procedures and instrumentation. In this work instead, we propose an approach which exploits the fundamental properties of the substrate to direct the growth of the next layer, here controlled by an electrochemical potential.

Acid-assisted polymerization: the novel synthetic route of sensing layers based on PANI films and chelating agents protected by non-biofouling layer for Fe or Fe potentiometric detection.

A new synthetic method for the fabrication of a sensing layer is presented. PANI films as an ion-to-electron transducer were prepared acid-assisted polymerization in concentrated formic acid (HCOOH) in the presence of ethanol and ammonium persulfate (APS, as the initiator). The ratio of monomer to ammonium persulfate was 1 : 0.

Potentiometric Performance of Ion-Selective Electrodes Based on Polyaniline and Chelating Agents: Detection of Fe or Fe Ions.

We constructed a sensor for the determination of Fe and/or Fe ions that consists of a polyaniline layer as an ion-to-electron transducer; on top of it, chelating molecules are deposited (which can selectively chelate specific ions) and protected with a non-biofouling poly(2-methyl-2-oxazoline)s layer. We have shown that our potentiometric sensing layers show a rapid response to the presence of Fe or Fe ions, do not experience interference with other ions (such as Cu), and work in a biological environment in the presence of bovine serum albumin (as a model serum protein). The sensing layers detect iron ions in the concentration range from 5 nM to 50 µM.