1. Could you explain the significance of your article to the non-specialist? 

Using a simple concept of "LEGO building bricks" we have developed a new family of polymers with an unusual combination of properties. These new polymers consist of two components: the dialkylbithiophene component assures solution processibility and facilitates the transport of charge carriers to the electrode and the oligoanilinethiophene component which introduces a H₃O⁺ concentration dependent electrochemical activity. The new polymers can serve as pH sensors with optical (NIR, Raman) or electrochemical (E_oc) detection. They can also be applied for sensing of pH dependent electrochemical processes.

2. What has motivated you to conduct this work? 

Our motivation was to prepare a processible polymer which would combine properties of poly(alkylthiophene)s and polyanilines - the two most extensively studied conductive polymers. Both families of conductive polymers show diversified chemistry and electrochemistry, however of different nature. Poly(alkylthiophene)s show a redox activity in nonaqueous electrolytes. Poly(aniline)s are electrochemically active both in nonaqueous and aqueous electrolytes. Moreover, because of the presence of strong basic sites in these polymers, their electrochemical responses are pH dependent. Our main goal was to prepare a "hybrid" polymer which, while retaining processing properties of poly(alkylthiophene)s, would exhibit pH dependent electrochemical response typical of polyanilines. Such polymers deposited in a form of a thin layer on a suitable substrate can serve as chemical or electrochemical sensors of different types. 

3. Where do you see this work developing in the future? 

The synthetic approach presented in the paper can easily be generalized to grafting of functional substituents other than oligoanilines. For example it can be applied for the introduction of complexing sites suitable for ion-selective electrodes, catalytically active sites, groups introducing non-linear optical properties, groups promoting self-organization via interchain molecular recognition etc.

4. Are there any particular challenges facing research in this area?

In the area of organic electronics and in the fabrication of modified organic microelectrodes there exists a large demand for electroactive polymers which can be easily micropatterned on a suitable substrate. The synthetic strategy proposed in the paper facilitates such pattering. For example the precursor polymer can be deposited on a micropatterned metal electrode via electropolymerization and then modified with suitable functional groups via a post-polymerization functionalization process. Micropatterning can also be achieved without the use of electrochemical methods. For example, by modifying the surface of a micropatterned electrode with functional groups capable of molecular recognition and simultaneous post-functionalizing the precursor polymer with complementary groups participating in the molecular recognition process.