Amplification-free miRNA detection with CRISPR/Cas12a system based on fragment complementary activation strategy.

CRISPR/Cas12a systems have been repurposed as powerful tools for developing next-generation molecular diagnostics due to their -cleavage ability. However, it was long considered that the CRISPR/Cas12a system could only recognize DNA targets. Herein, we systematically investigated the intrinsic -cleavage activity of the CRISPR/Cas12a system (LbCas12a) and found that it could be activated through fragmented ssDNA activators.

Surface plasmon resonance sensor based on U-shaped photonic quasi-crystal fiber.

A high-sensitivity surface plasmon resonance (SPR) sensor is designed and analyzed numerically. The sensor is constructed on the eightfold U-shaped photonic quasi-crystal fiber (PQF) and coated with indium tin oxide (ITO). The coupling between the core mode and surface plasmon polariton mode is enhanced due to shortening of the distance between the core and the ITO layer, so that the PQF-SPR sensor exhibits high refractive index (RI) sensitivity in the near-infrared region.

High-sensitivity SPR sensor based on the eightfold eccentric core PQF with locally coated indium tin oxide.

A highly sensitive surface plasmon resonance (SPR) sensor comprising an eccentric core photonic quasi-crystal fiber (PQF) coated with indium tin oxide is designed and numerically analyzed. The novel, to the best of our knowledge, structure with an eccentric core layout and local coating not only strengthens coupling between the core mode and surface plasmon polariton mode but also provides higher refractive index sensitivity in the near-infrared region. Analysis based on the finite element method to assess the performance of the sensor and optimize the structural parameters reveals that the maximum wavelength sensitivity and resolution are 96667 nm/RIU and 1.

Surface plasmon resonance sensor based on eccentric core photonic quasi-crystal fiber with indium tin oxide.

A sensing device composed of an eccentric core photonic quasi-crystal fiber based on surface plasmon resonance is designed using indium tin oxide (ITO) as the sensitive materials. The ITO film is deposited on the outside surface of the fiber to excite plasmonic interactions and facilitate refractive index (RI) detection. This eccentric core structure makes the evanescent field coupled effectively with analyte to achieve higher sensitivity.