Polyacrylonitrile/Reduced Graphene Oxide Free-Standing Nanofibrous Membranes for Detecting Endocrine Disruptors

Endocrine-disrupting chemicals (EDCs) are emerging pollutants whose uncontrolled release in natural aquatic environments can pose risks to human and animal health. In this scenario, the development of simple, low-cost, and sensitive methods to detect trace amounts of EDCs in the environment is highly sought. In this work, a nanofiber-based sensor was fabricated by functionalizing a polyacrylonitrile (PAN) electrospun nanofibrous membrane with reduced graphene oxide (rGO) to be used as a flexible and free-standing electrode to detect EDCs through electrical impedance measurements. The rGO was obtained from graphene oxide using a hydrothermal route, while the PAN/rGO composite membrane was prepared through vacuum filtration. The rGO provided high electrical conductivity to the membrane, which presented a good performance in the detection of endocrine hormones. The electrical resistance variation enabled the detection of 17α-ethinylestradiol (EE2) in a linear range between 10–5 and 10–11 mol L–1. Moreover, by using the principal component analysis (PCA) for data treatment, the sensor was able to discriminate EE2, estrone, estradiol, and progesterone at 100 pmol L–1 in real river water samples. These results open up the possibility to fabricate in a simple way functionalized nanofibrous membranes to be used as sensing material for the detection of varied analytes with high sensitivity and low cost.