Development of Cantilever Nanoimmunosensors Applied to the Detection of β-Estradiol and Estrone in Water

Endocrine-disrupting are chemical substances that have hormonal activity and can potentially cause diseases to the endocrine system in animals, including humans. Therefore, there is a necessity of to develop sensitive, specific, and reliable analytical systems capable to detect compounds using low-cost and portable devices. In this study, were developed cantilever nanoimmunosensors for β-estradiol and estrone hormones detection in tap water. The cantilever nanoimmunosensorswere functionalized with antiβ-estradiol and anti-estrone antibodies. The device surface was analyzed by scanning electron microscopy, atomic force microscopy, and polarization modulation infrared reflection absorption spectroscopy and showed an efficient functionalization with conformational changes. Results demonstrated a linear relationship in a range between 0.01 and 50 μg/L. A limit of detection of 9 and 26 ng/L (0.009 and 0.026 ppb) and sensitivity of 0.390 and 0.140 V/ng were observed for β-estradiol and estrone hormones using the cantilever nanoimmunosensors functionalized anti-β-estradiol and antiestrone, respectively. These results demonstrate that these devices are suitable to be apply in tap water for quality monitoring and detection β-estradiol and estrone.