An efficient route towards functional PPV-derivatives for sensor applications

Abstract

Poly(p-phenylene vinylene)(PPV) derivatives are conjugated polymers for which a variety of novel opto-electronic applications are envisioned, including (bio)sensors. Conjugated polymer based sensor designs are often based on the incorporation of specific recognition elements as functional groups. However, the incorporation of complex functional groups is frequently not compatible with polymerization procedures. To avoid these compatibilities, we have developed a new synthetic strategy that allows a reproducible and straightforward post-polymerization funcionalization. Our approach starts from a carboxylic acid functionalized PPV, i.e. poly(1,4-(2-(5-carboxypentyloxy)-5-methoxyphenylene)vinylene), which was obtained via the sulfinyl precursor route. This polymer acts as the platform for further functionalization. Using Mitsunobu reaction conditions various functionalized PPV derivatives have been prepared. Improvements in reproducibility and solubility were made by using the DCC/DMAP-esterification method. The presented functionalization methods are well suitable for the introduction of complex recognition elements. This will allow the use of PPV-type polymers as the transducer layers in (bio)sensor applications.