Portable “dual-signal-on” colorimetric and photothermal biosensor for accurate detection of Hg2+ based on split Cas12a-mediated cascade strand displacement and phosphorothioate-modified G-quadruplex DNAzyme

Key Points

• This research aims to develop a portable biosensor for accurately detecting mercury ions using advanced molecular techniques.
• Utilized a split crRNA along with Cas12a for biosensor design.
• Combined colorimetric and photothermal signals for detection.
• Implemented a cascade strand displacement mechanism for enhanced sensitivity.
• Used phosphorothioate-modified G-quadruplex DNAzyme for specific ion recognition.
• Achieved high sensitivity and accuracy in detecting Hg2+ ions.
• Demonstrated effective dual-signal response enabling clear detection.
• Showed potential applications in environmental monitoring of toxic metals.