A fluorescence biosensor with a dual-function DNA probe targeting the activated estrogen receptor for estrogenic...

Area of Science:

• Environmental Science
• Biochemistry
• Analytical Chemistry

Background:

• Endocrine disruption chemicals (EDCs), including environmental estrogens (EEs), pose risks to environmental safety and public health.
• Conventional methods for detecting EEs are often costly, time-consuming, and lack reproducibility.

Purpose of the Study:

• To develop a rapid, robust, and high-throughput fluorescence biosensor for evaluating the estrogenic activity of environmental chemicals.
• To mimic the molecular interactions within the estrogen receptor (ER) signaling pathway for accurate detection.

Main Methods:

• A dual-function DNA probe was designed, incorporating an ER binding sequence and a dye-binding sequence for the OliGreen fluorescent dye.
• Estrogenic activity was measured by the reduction in fluorescence anisotropy of OliGreen upon binding of activated ER complexed with the DNA probe.
• The biosensor was validated using estradiol, an ER antagonist, and five emerging contaminants (RDP, TPHP, TCIPP, OBS, PFOA).

Main Results:

• The biosensor demonstrated a dose-response for estradiol with an EC50 of 3 nM and a lower detection limit of 0.5 nM.
• No response was observed with a known ER antagonist, indicating specificity.
• Detection of emerging contaminants showed results consistent with cell assays, with high recovery rates in spiked river water samples (RDP: 103%, TPHP: 93%, OBS: 98%).

Conclusions:

• The developed fluorescence biosensor provides a significantly faster, more robust, and easier-to-use method for screening estrogenic chemicals compared to traditional cell assays.
• This technique offers a promising new high-throughput approach for the detection of environmental estrogens and contaminants.