A novel photonic crystals electrochemical synchronous dual-mode sensor for perfluorooctanoic acid detection in...

Perfluorooctanoic acid (PFOA) was a kind of persistent organic pollutant, which was the main active ingredient in antifouling treatments for textiles and leather products. However, PFOA was still produced and used on a large scale in many countries and regions with rapid industrialization. Therefore, it was significant to establish a detection method for PFOA in textiles. In this paper, we constructed a novel photonic crystals electrochemical synchronous dual-mode sensor based on differential pulse voltammetry (DPV) and electrochemiluminescence (ECL) for perfluorooctanoic acid detection in textiles.

AgBiS₂ QDs with high ECL activity and good biocompatibility were prepared as nano-emitters. Meanwhile, silica (SiO₂) optical microspheres were used to form photonic crystals through interfacial self-assembly. Then, molecularly imprinted polymers (MIPs) were prepared on the voids of SiO₂ photonic crystals with dopamine (DA) as the functional monomer and PFOA as the template molecule. The photonic crystals significantly enhanced the ECL signal and increased the density of specific recognition sites in MIPs, which greatly improved the sensitivity of detection. In addition, liquid-liquid extraction of textiles using deep eutectic solvent (menthol: octanol 1:1) was used to pre-enrich PFOA. Finally, both DPV and ECL signals were generated in the synchronous dual-mode sensing system to detect PFOA successfully.

The ECL and DPV response showed good linear relationships with the concentration of PFOA with the ranges of 0.005 μM-50 μM and 0.2 μM-5.0 μM and the detection limits of 0.00168 μM and 0.067 μM, respectively. This sensor with the synchronized DPV-ECL dual-mode analysis introduced an innovative and sensitive method for PFOA detection.