High sensitivity optical biosensors based on conjugated polymers

Conjugated polymers (CPs) with large, delocalized molecular structures exhibit unique optical characteristics, which can be used as excellent sensing elements. Recently, the use of water-soluble CPs as either chemical or biological sensor elements has received intense research interest. The sensing mechanism can be variable with different conjugated polymers used. For example, million-fold signal amplification can be achieved when electron/energy that moves along a conjugated chain is transferred to an appropriate acceptor ultrafastly, so the sensitivity of the biosensor can be improved remarkably. Some CPs' optical characteristics can be changed when the conformations of the conjugated backbone or the profile substitutes are changed. With this, the colorimetric and fluorometric biosensors are designed by changing the conformation of the probes mediated by the combination of the specific targets.