Electrochemical biosensor for estrogenic substance using lipid bilayers modified by Au nanoparticles

Area of Science:

• Environmental Science
• Analytical Chemistry
• Nanotechnology

Background:

• Growing demand for sensitive detection of environmental xenoestrogens.
• Existing methods for xenoestrogen detection often rely on radio- or enzyme-labeled compounds.
• Need for direct and efficient screening technologies for estrogenic substances.

Purpose of the Study:

• To develop a nanostructure electrochemical biosensor for direct detection of xenoestrogens.
• To utilize estrogen receptor (ER) binding for sensing without labeling.
• To evaluate the biosensor's performance in detecting natural and synthetic estrogens.

Main Methods:

• Fabrication of the biosensor by immobilizing ERs in a supported bilayer lipid membrane (s-BLM) modified with gold nanoparticles.
• Characterization of modified electrodes using cyclic voltammetry and impedance spectroscopy.
• Detection of 17beta-estradiol, bisphenol A, and 4-nonylphenol.

Main Results:

• The biosensor detected 17beta-estradiol with a linear correlation from 5 to 150 ng/L and a detection limit of 1 ng/L.
• Satisfied sensitivity and quantitative results were achieved for other xenoestrogens like bisphenol A and 4-nonylphenol.
• Good reliability and repeatability were demonstrated, with gold nanoparticles enhancing sensitivity and stability.

Conclusions:

• The developed nanostructure electrochemical biosensor provides a sensitive and reliable method for direct xenoestrogen detection.
• The biosensor's performance in analyzing water samples showed good agreement with cell proliferation assays.
• This technology offers a promising tool for environmental screening of estrogenic substances.