In-situ DNA hybridization detection based on a reflective microfiber probe

Area of Science:

• Photonics
• Biotechnology
• Nanotechnology

Background:

• Label-free biosensing is crucial for real-time molecular detection.
• Microfiber-based sensors offer miniaturization and high sensitivity potential.
• DNA hybridization detection is fundamental for diagnostics and research.

Purpose of the Study:

• To propose and demonstrate a novel label-free biosensor for in-situ, real-time DNA hybridization detection.
• To utilize a reflective microfiber probe for enhanced sensing capabilities.
• To assess the sensitivity, specificity, and repeatability of the developed biosensor.

Main Methods:

• Fabrication of a reflective microfiber probe via flame-stretching of a biconical microfiber.
• Functionalization of the microfiber surface with Poly-L-lysine (PLL) and synthetic DNA sequences.
• Real-time monitoring of DNA hybridization using spectral variations in a microfiber modal interferometer.

Main Results:

• Demonstrated successful in-situ, real-time detection of DNA hybridization.
• Achieved a minimum detectable concentration of 10 picomolar (pM) with good repeatability.
• Confirmed high detection specificity by testing against non-complementary single-stranded DNA (ssDNA).

Conclusions:

• The proposed reflective microfiber biosensor is a sensitive and specific platform for DNA detection.
• The sensor's simple fabrication and compact size offer significant advantages.
• This technology holds great potential for applications in disease diagnosis, medicine, and environmental science.