Development of a sensitive and facile DNA biosensor for the determination of trace levels of bisphenol A concentration based on DNA damage

Bisphenol A is one of the most important endocrine disruptors due to its toxicity and environmental presence. It is also used as raw material in the production phase of industrial products. For the health of humans and the environment, the detection of bisphenol A is important. Herein, a simple and sensitive electrochemical DNA biosensor based on a screen-printed carbon electrode (SPCE) modified magnetite nanoparticles and fish sperm DNA was developed to quantify bisphenol A based on its damage to DNA. The fsDNA/Fe3O4Np-SPCE was prepared layer by layer and characterized using cyclic voltammetry, electrochemical impedance spectroscopy, field emission scanning electron microscopy, atomic force microscopy, and energy dispersive X-ray Spectroscopy. The results indicated that Fe3O4Np promotes electron transfer between DNA and electrode. DNA damage of BPA was investigated based on significant changes in the oxidation peaks of guanine, adenine, and thymine moieties without any indicator. The proposed sensor was also used to quantify bisphenol A. Its detection limit was 2.77 pM, 35.00 pM, and 12.84 pM for G, A, and T, respectively. The sensor was applied to real water samples with satisfactory results. The DNA sensor exhibited acceptable stability, good reproducibility, and a feasible interference effect.