Enhanced Bisphenol A Sensing in Water Using 1-D H Exchanged -MnO-Based Impedimetric Sensor

Abstract

Bisphenol A (BPA) is a known endocrine disruptor with estrogen-like effects, which causes damage to human organs. BPA can affect the immune, reproductive, and neuroendocrine systems and is also carcinogenic. Herein, highly selective electrochemical sensing of BPA using H+-exchanged <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha $ </tex-math></inline-formula> -MnO2 in water under room conditions was developed. H+-exchanged <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha $ </tex-math></inline-formula> -MnO2 was synthesized via ion exchange. The synthesized material was characterized using an X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS), which confirms a successful synthesis of 1-D H+-exchanged <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha $ </tex-math></inline-formula> -MnO2. A nano-enabled, label-free electrochemical sensor was fabricated by employing synthesized materials. The sensor prominently showed high sensitivity of 0.64 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{k}\Omega $ </tex-math></inline-formula> /nM/mm2 and a lower limit of detection (LoD) of 16 nM. The equivalent Randel circuit was modeled for electron transfer kinetics evaluation. Additionally, the shelf life analysis confirmed the stability and reproducibility of the designed sensor over 30 days. Moreover, the sensor is highly selective toward BPA against other organic compounds. So, H+-exchanged <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha $ </tex-math></inline-formula> -MnO2-based BPA sensor provides a feasible and novel avenue to detect BPA in water under ambient conditions for health safety purposes.