Highly sensitive detection of lead in tea using a DNA-based CRISPR signal amplification system

The detection platform achieves a detection limit of 67.53 pM for lead ion contamination in tea.

• The platform integrates a multifunctional DNAzyme machine with the CRISPR/Cas12a system for enhanced detection.
• Activation of the DNA machine leads to multiple cycles that generate a poly-A sequence, which then activates Cas12a.
• This activation triggers trans-cleavage of fluorescent probes, resulting in significant signal amplification.
• The assay demonstrates a wide linear range of 0.01-100 nM and high recovery rates above 96% in real tea samples.
• The approach simplifies assay design by eliminating the need for auxiliary probes while maintaining specificity.

Simplified