Three-Dimensional DNA Nanostructure-Assisted Multiplexed Aptamer Assay for Simultaneous Detection of...

Area of Science:

• Biotechnology
• Environmental Science
• Analytical Chemistry

Background:

• Endocrine-disrupting chemicals (EDCs) pose significant environmental and health risks.
• Simultaneous detection of multiple EDCs is crucial for comprehensive risk assessment.
• Existing detection methods often lack multiplexing capabilities or require complex sample preparation.

Purpose of the Study:

• To develop a multiplexed aptasensor for simultaneous detection of bisphenol A (BPA), phthalic acid esters (PAEs), and nonylphenol (NP).
• To utilize a three-dimensional (3D) DNA nanostructure framework for enhanced sensor performance.
• To validate the sensor's applicability in real-world sample matrices.

Main Methods:

• Fabrication of a tetrahedral 3D-DNA nanostructure framework.
• Immobilization of aptamers onto magnetic beads functionalized with 3D-DNA nanostructures.
• Quantitative detection using quantum dot (QD) fluorescence quenching upon target binding.
• Validation of multiplexing, selectivity, dynamic range, and limit of quantification (LOQ).

Main Results:

• The aptasensor successfully detected NP, PAEs (specifically DBP), and BPA simultaneously.
• Demonstrated dynamic ranges: 1-100 ng/mL for NP, 0.001-100 ng/mL for DBP, and 0.0005-100 ng/mL for BPA.
• Achieved low LOQs: 1 ng/mL for NP, 1 pg/mL for DBP, and 0.5 pg/mL for BPA.
• High recovery rates observed when applied to spiked tap water and beverages.

Conclusions:

• The developed 3D DNA nanostructure-based aptasensor offers a sensitive and selective platform for multiplexed EDC detection.
• The assay demonstrates practical applicability for analyzing EDCs in complex environmental samples.
• This approach provides a valuable tool for monitoring EDC contamination and assessing associated risks.