Microfluidic plasmonic color reading chips and methods

Patent metadata

Field	Value
Publication number	US-12590340-B2
Application number	US-202217662732-A
Country	US
Kind code	B2
Filing date	May 10, 2022
Priority date	May 10, 2021
Publication date	Mar 31, 2026
Grant date	Mar 31, 2026

Abstract

There is provided a microfluidic chip for sensing an analyte in a sample by colorimetry. The microfluidic chip comprises: an inlet adapted to receive the sample; an incubation chamber having an incubation chamber inlet fluidly connected to the inlet downstream thereof, to incubate the analyte in the sample; a filter barrier fluidly connected to the incubation chamber, downstream of the incubation chamber inlet; a sensing chamber fluidly connected to the incubation chamber, downstream of the filter barrier, the sensing chamber having a plasmonic nanosurface, the plasmonic nanosurface including nanostructures protruding from the plasmonic nanosurface, the nanostructures having a size that is smaller than that of the diffraction limit of light, the nanostructures having a metallic layer that is plasmon-supported on top of a back reflector layer; and an outlet fluidly connected to the sensing chamber downstream thereof.

First claim

What is claimed is:

1 . A microfluidic chip for sensing an analyte in a sample by colorimetry, the microfluidic chip comprising:
an inlet adapted to receive the sample, an incubation chamber having an incubation chamber inlet fluidly connected to the inlet downstream thereof, to incubate the analyte in the sample; a filter barrier fluidly connected to the incubation chamber, downstream of the incubation chamber inlet; a sensing chamber fluidly connected to the incubation chamber, downstream of the filter barrier, the sensing chamber having a plasmonic nanosurface, the plasmonic nanosurface including nanostructures protruding from the plasmonic nanosurface, the nanostructures having a size that is smaller than that of the diffraction limit of light, the nanostructures having a metallic layer that is plasmon-supported on top of a back reflector layer; and an outlet fluidly connected to the sensing chamber downstream thereof.

2 . The microfluidic chip of claim 1 , wherein the nanostructures have a diameter between 200 nm and 1000 nm.

3 . The microfluidic chip of claim 1 , wherein nanocavities are defined in between the nanostructures, the nanocavities define an interparticle gap of between 20 nm and 500 nm between the nanostructures.

4 . The microfluidic chip of claim 1 , wherein the plasmonic nanosurface is free of color pigments.

5 . The microfluidic chip of claim 1 , wherein the filter barrier comprises at least two rows of micropillars.

6 . The microfluidic chip of claim 1 , wherein the filter barrier is enclosed in the incubation chamber and occupies a portion of a total volume thereof.

7 . The microfluidic chip of claim 1 , wherein the nanostructures comprise a monolayer of polystyrene nanoparticles coated by the back reflector layer and further coated by the metallic layer.

8 . The microfluidic chip of claim 1 , wherein the microfluidic chip further comprises a heating element.

9 . The microfluidic chip of claim 1 , wherein the back reflector layer is selected from the group consisting of ZnO, TiO 2 , hydrogen silsesquioxane (HSQ), AZ MiR™, and polymethyl methacrylate (PMMA).

10 . The microfluidic chip of claim 1 , wherein the metallic surface comprises at least one of Al, Ag and Au.

11 . The microfluidic chip of claim 7 , wherein the polystyrene nanoparticles have a diameter of between 200 nm to 1000 nm.

12 . The microfluidic chip of claim 1 , wherein the back reflector has a thickness of 10 to 500 nm.

13 . The microfluidic chip of claim 1 , wherein the metallic surface has a thickness of 5 to 100 nm.

14 . The microfluidic chip of claim 1 , wherein the inlet, the incubation chamber, the sensing chamber and the outlet are defined in a layer of negative photoresist forming part of the microfluidic chip.

15 . The microfluidic chip of claim 1 , wherein the microfluidic chip includes a silicon base layer, an epoxy-based negative photoresist layer onto the silicon base layer, and a curable transparent polymer layer, the incubation chamber and the sensing chamber defined in the epoxy-based negative photoresist layer.

16 . A method of sensing an analyte in a sample comprising:
providing a microfluidic chip as defined in claim 1 ; providing the sample at the inlet; incubating the sample in the incubation chamber for a predetermined period of time; flowing the sample across the filter barrier to the sensing chamber; and analyzing a plasmonic color change of the sample.

17 . The method according to claim 16 , wherein further comprising providing a colorimetric sensor at a second inlet of the microfluidic chip.

18 . The method according to claim 17 , further comprising mixing the colorimetric sensor and the sample in microchannels of the microfluidic device.

19 . The method according to claim 16 , further comprising, before providing the sample at the inlet, mixing the sample with a colorimetric sensor.

20 . The method according to claim 16 , wherein the incubating of the sample in the incubation chamber comprises heating the microfluidic chip to induce a nucleic acid amplification of the analyte being a nucleic acid sequence.

Assignees

• The Royal Institution For The Advancement Of Learning/Mcgill Univ

Inventors

• MAHSHID Sara
• Jalali Mahsa
• Abdelwahab Tamer
• Del Real Mata Carolina

Classifications

• B01L2300/0681

  Filter · CPC title

• B01L2300/0883

  Serpentine channels · CPC title

• B01L2300/1805

  Conductive heating, heat from thermostatted solids is conducted to receptacles, e.g. heating plates, blocks · CPC title

• B01L2200/16

  Reagents, handling or storing thereof · CPC title

• C12Q1/6844

  Nucleic acid amplification reactions · CPC title