Universal Signal Switch Based on a Mesostructured Silica Xerogel-Confined ECL Polymer for Epigenetic Quantification

Area of Science:

• Biochemistry
• Nanotechnology
• Analytical Chemistry

Background:

• Developing accurate electrochemiluminescence (ECL) signal switches to avoid nonspecific responses is a significant challenge.
• Detecting low-abundance epigenetic markers in complex samples requires highly sensitive and specific methods.

Purpose of the Study:

• To construct a universal ECL signal switch for accurate detection of epigenetic markers.
• To demonstrate the feasibility of the signal switch for quantifying 5-hydroxymethylcytosine (5hmC).

Main Methods:

• Utilized a luminophore-quencher pair: mesoporous silica xerogel-confined polymer (luminophore) and gold nanoparticles (Au NPs) (quencher).
• Employed a CRISPR/Cas12a system with a double-stranded DNA (dsDNA) tag and recombinant polymerase amplification (RPA) for specific 5hmC detection.
• Leveraged Au NPs-mediated energy transfer quenching for signal switching.

Main Results:

• The ECL polymer in mesoporous silica xerogel exhibited specific quenching dependence on Au NPs.
• RPA amplification generated dsDNA tags that activated CRISPR/Cas12a trans-cleavage activity.
• The system enabled precise quantification of 5hmC, demonstrating high specificity and stability.

Conclusions:

• The developed ECL signal switch offers improved luminophore stability and prevents nonspecific responses.
• This provides a new paradigm for constructing high-precision biosensors for epigenetic markers.
• The system shows potential for accurate detection in complex biological samples.