Multiplex fluorescent particle detection using spatially distributed excitation

摘要

A chip-scale optical approach to performing multi-target detection is based on molecular biosensing using fiber-optic based fluorescence or light scattering detection in liquid-core waveguides. Multiplexing methods are capable of registering individual nucleic acids and other optically responsive particles, and are ideal for amplification-free detection in combination with the single molecule sensitivity of optofluidic chips. This approach overcomes a critical barrier to introducing a new integrated technology for amplification-free molecular diagnostic detection. Specific examples of liquid-core optical waveguides and multi-mode interferometers are described; however, they can be implemented in a number of different ways as long as a series of excitation spots is created whose spacing varies with the excitation wavelength.

主权项

1. A method for using spatially distributed interferometric excitation in an optical diagnostic instrument, comprising:
using a multi-mode interferometer (MMI) to create a wavelength dependent excitation pattern in a fluidic channel in direct contact with the MMI, wherein the excitation pattern includes a wavelength-dependent number, k, of light spots in the fluidic channel; causing a fluorescent or light scattering particle to flow in the channel past the MMI and the entire excitation pattern so as to produce k fluorescence or light scattering pulses at time steps Δt, wherein Δt depends on the spacing of the light spots in the fluidic channel; detecting the k fluorescence or light scattering pulses and producing a measured detector signal S(t); and identifying the fluorescent or light scattering particle based on a predefined algorithm and the measured detector signal S(t).