Ultra-sensitive DNA detection with single-base mismatch resolution using a tapered thin-diameter photonic crystal...

Area of Science:

• Optoelectronics and Photonics
• Biomedical Engineering
• Nanotechnology

Background:

• Photonic crystal fibers (PCFs) offer unique light-confining properties for sensing applications.
• Developing highly sensitive and specific biosensors is crucial for early disease diagnosis and environmental monitoring.
• Existing biosensors often face limitations in detection limits and specificity.

Purpose of the Study:

• To propose and demonstrate a novel tapered thin-diameter photonic crystal fiber interferometer (TTD-PCFI) biosensor.
• To achieve ultra-low limit of detection (LoD) and high specificity for DNA hybridization detection.
• To explore the potential of TTD-PCFI for label-free, real-time biological detection.

Main Methods:

• Fabrication of the TTD-PCFI using arc-discharged melting and adiabatic tapering.
• Characterization of the TTD-PCFI for optical properties, including refractive index sensitivity (3842.5 nm/RIU).
• Demonstration of DNA hybridization detection across a concentration range from 1 fM to 1 pM.

Main Results:

• The TTD-PCFI exhibited a high refractive index sensitivity and a low optical loss.
• Achieved DNA hybridization detection sensitivity of 632 pm/lg(fM).
• Demonstrated an ultra-low limit of detection (LoD) of 410 attomolar (aM) and single-base mismatch detection.

Conclusions:

• The developed TTD-PCFI biosensor offers superior performance for DNA detection.
• The label-free biosensor exhibits ultra-low LoD, high specificity, and real-time detection capabilities.
• This technology holds significant promise for applications in disease diagnosis, microbial detection, and environmental science.