Click-based amplification: designed to facilitate various target labelling modes with ultralow background...

Area of Science:

• Biochemistry
• Molecular Biology
• Bioimaging

Background:

• Signal amplification is crucial for sensitive bioimaging.
• Existing methods like tyramide signal amplification (TSA) have limitations.
• Click chemistry offers versatile labeling strategies.

Purpose of the Study:

• To develop and evaluate a novel fluorescent signal amplification method, termed Click-based amplification.
• To assess the efficiency and applicability of Click-based amplification across various labeling techniques.
• To compare Click-based amplification with existing methods like TSA.

Main Methods:

• Utilized picolyl azide (pAz) as a functional group on a streptavidin-based amplifier.
• Integrated Click-based amplification with chemical labeling, genetic incorporation, and covalent inhibitor probe labeling.
• Applied the method to fixed HeLa cells and mouse intestinal tissue slices.

Main Results:

• Achieved 3.0-12.7 fold signal amplification on fixed HeLa cells.
• Demonstrated superior performance compared to TSA, with lower nonspecific amplification and higher signal-to-noise ratio.
• Successfully enhanced fluorescence signals in mouse intestinal tissue, enabling detection of afatinib-N3 and revealing off-target toxicity.

Conclusions:

• Click-based amplification is an effective and versatile method for fluorescent signal enhancement in bioimaging.
• The technique shows significant advantages over TSA, particularly for challenging applications like tissue imaging.
• Click-based amplification holds promise for advancing bioimaging studies and drug toxicity assessments.