Digital DNA detection based on a compact optofluidic laser with ultra-low sample consumption

Area of Science:

• Optics
• Molecular Biology
• Biotechnology

Background:

• Existing DNA lasers offer quasi-digital detection but suffer from high sample consumption and complex dye labeling.
• A persistent fluorescence background in current systems hinders true digital detection, necessitating spectral analysis.
• These limitations impede the practical application of DNA lasers in diagnostics.

Purpose of the Study:

• To develop a novel optofluidic laser system for highly sensitive and truly digital DNA detection.
• To overcome the drawbacks of existing DNA laser technologies, including sample volume and labeling complexity.
• To demonstrate a DNA laser with a single layer of DNA as the gain medium, suppressing background fluorescence.

Main Methods:

• Fabrication of an optofluidic laser with a single layer of DNA molecules serving as the gain material.
• Utilizing intercalating dye staining by simple immersion of the microcavity, avoiding pre-analysis labeling.
• Characterization of laser emission upon interaction with target and non-target DNA sequences.

Main Results:

• The proposed DNA laser generates intensive laser emission for target DNA, comparable to existing systems.
• Unnecessary fluorescence background is effectively suppressed, enabling true digital detection with a single laser pulse.
• DNA sample consumption is reduced by orders of magnitude due to the single-layer DNA configuration.
• The simplified dye-staining method eliminates complex pre-labeling steps.

Conclusions:

• The developed optofluidic DNA laser provides a truly digital, highly sensitive, and efficient method for DNA detection.
• This approach significantly reduces sample requirements and simplifies the experimental workflow.
• The technology holds promise for advancing DNA sensing applications in various fields.