Engineering a G-quadruplexes topology switch-regulated sensor array using a single fluorescent probe for pattern...

Area of Science:

• Analytical Chemistry
• Biochemistry
• Environmental Science

Background:

• Metal ions are crucial in biological and environmental systems, but their dysregulation causes disease.
• Traditional single-analyte detection methods fail to identify multiple metal ions simultaneously.
• Existing fluorescent sensor arrays often require multiple probes, limiting analytical performance.

Purpose of the Study:

• To develop a single fluorescent probe-based sensor array for simultaneous detection and differentiation of multiple metal ions.
• To overcome the limitations of disparate signal moieties in traditional sensor arrays.
• To establish a novel strategy for metal ion detection based on nucleic acid topology.

Main Methods:

• A single G-quadruplexes (G4s) topologies-specific benzothiazole fluorescent probe (TDF) was developed.
• Three CEBwt variants (CEBmx) were selected to exhibit varying G4-switch and topological stability influenced by metal ions.
• Fluorescence-based fingerprint patterns were analyzed using linear discriminant analysis (LDA) and hierarchical clustering analysis (HCA).

Main Results:

• The sensor array successfully detected and differentiated metal ions like K+, Na+, and Cu2+ with low detection limits (LODs).
• The method achieved LODs of 0.047 mM for K+, 0.92 mM for Na+, and 0.0079 mM for Cu2+.
• The array identified 8 types of metal ions, mixtures, and heavy metals in real water samples with high efficiency.

Conclusions:

• The developed single fluorescent probe-based sensor array offers a breakthrough in metal ion detection, overcoming "lock-key" limitations.
• This nucleic acid topology-regulated fluorescent sensor array provides a powerful platform for environmental and ecological research.
• The facile, label-free detection method demonstrates significant potential for analyzing complex metal ion systems.