A fluorescent conjugated polymer-based ratiometric aptasensor for highly specific and robust detection of perfluorooctanoic acid

We develop a fluorescent conjugated polymer-based ratiometric aptasensor for highly specific and robust detection of perfluorooctanoic acid (PFOA). The presence of PFOA can induce aptamer folding and consequently the enhancement of the fluorescence resonance energy transfer (FRET) efficiency, facilitating the ratiometric detection of PFOA with a detection limit of 27 nM and excellent selectivity. This robust aptasensor can discriminate PFOA from common anionic surfactants, which remains a challenge for conjugated polymer-based PFOA sensors, and visually measures PFOA in complex aqueous samples.