Efficient microfluidic particulate matter (PM) removal device using staggered herringbone micromixers

Patent metadata

Field	Value
Publication number	US-11376535-B2
Application number	US-201916401402-A
Country	US
Kind code	B2
Filing date	May 2, 2019
Priority date	May 3, 2018
Publication date	Jul 5, 2022
Grant date	Jul 5, 2022

Abstract

Microfluidic devices to efficiently remove particulate matter (PM) in air are provided, as are methods of fabricating and using the same. A device can include a channel having a structure configured to generate chaotic advective flow in air within the channel. The channel structure can include a plurality of SHMs disposed within the channel, where each SHM comprises a plurality of grooves each having a width of 200 μm or less and a spacing between each groove of 200 μm or less. The plurality of SHMs can be configured to introduce microvortices in air flow within the channel.

First claim

What is claimed is:

1. A microfluidic device, comprising:
a channel having a structure configured to generate chaotic advective flow of air within the channel,
wherein the structure of the channel comprises an adhesive surface,
wherein the structure of the channel comprises a plurality of staggered herringbone micromixers (SHMs) disposed within the channel,
wherein each SHM comprises a plurality of grooves each having a width of 100 μm or less and a spacing between each groove of 100 μm or less, and
wherein the structure of the channel generates chaotic advective flow by introducing microvortices in the air within the channel.

2. The microfluidic device according to claim 1 , wherein the width of each groove is 50 μm or less and the spacing between each groove is 50 μm or less.

3. The microfluidic device according to claim 1 , wherein the width of each groove is about 50 μm and the spacing between each groove is about 50 μm.

4. The microfluidic device according to claim 1 , wherein the SHMs of the plurality of SHMs are stacked within the channel to form a stack of SHMs, and
wherein the SHMs are disposed such that patterns thereof alternate each half cycle, by mirroring each other, throughout the stack of SHMs.

5. The microfluidic device according to claim 1 , wherein the microfluidic device is configured to remove particulate matter with a diameter of less than 2.5 μm (PM 2.5 ) at a removal efficiency of at least 90%, and
wherein the microfluidic device is configured to remove particulate matter with a diameter of from 2.5 μm to 10 μm (PM 2.5-10 ) at a removal efficiency of at least 99%.

6. The microfluidic device according to claim 1 , wherein each SHM comprises at least 10 grooves.

7. The microfluidic device according to claim 1 , wherein the structure of the channel comprises polydimethylsiloxane (PDMS), silicone, a plastic material covered with an adhesive surface, or a combination thereof.

8. The microfluidic device according to claim 1 , wherein the channel has a width of at least 2.4 mm, a height of at least 50 μm, and a length of at least 50 mm.

9. The microfluidic device according to claim 1 , wherein the channel has a width of at least 2.4 mm, a height of at least 50 μm, and a length of at least 50 mm,
wherein the SHMs of the plurality of SHMs are stacked within the channel to form a stack of SHMs,
wherein the SI IMs are disposed such that patterns thereof alternate each half cycle, by mirroring each other, throughout the stack of SHMs,
wherein each SHM comprises at least 10 grooves,
wherein the microfluidic device is configured to remove PM 2.5 at a removal efficiency of at least 90%,
wherein the microfluidic device is configured to remove PM 2.5-10 at a removal efficiency of at least 99%, and
wherein each SHM comprises PDMS, silicone, a plastic material covered with an adhesive surface, or a combination thereof.

10. A mask for filtering particulate matter, the mask comprising:
the microfluidic device according to claim 1 ; and
a check valve.

Assignees

• Univ Hong Kong Science & Tech

Inventors

• Chen Yangfan
• Chan Ho Nam
• Wu Hongkai

Classifications

• A62B7/10

  with filter elements · CPC title

• A62B9/06

  Mouthpieces; Nose-clips (for medical purposes A61M15/00) · CPC title

• B01D45/10 Primary

  which are wetted · CPC title

• B01L2300/0887

  Laminated structure · CPC title

• B01L3/502761

  specially adapted for handling suspended solids or molecules independently from the bulk fluid flow, e.g. for trapping or sorting beads or physically stretching molecules · CPC title