Fluid dispensing device in microchannels and microfluidic device

Patent metadata

Field	Value
Publication number	US-2025073711-A1
Application number	US-202218722331-A
Country	US
Kind code	A1
Filing date	Dec 22, 2022
Priority date	Dec 23, 2021
Publication date	Mar 6, 2025
Grant date	—

Abstract

A dispensing device, in a microfluidic device, includes branch channels branching from a main channel, and an air exhaust channel at branch channels ends. The main channel includes first in-channel resistant parts respectively near and on a downstream side of branching positions of the branch channels, and the air exhaust channel includes second in-channel resistant parts near merging positions. Each first in-channel resistant parts generates a greater surface tension disruption pressure than pressure generated by channel resistance from a branching position to a second in-channel resistant part. Each second in-channel resistant parts generates a greater surface tension disruption pressure than a sum of the surface tension disruption pressure of each of the first in-channel resistant parts and pressures generated by channel resistances from a first in-channel resistant part to a subsequent first in-channel resistant part, and from a subsequent branching position to a subsequent second in-channel resistant part.

First claim

1 . A fluid dispensing device in microchannels, comprising a main channel allowing fluid to flow down in one direction, a plurality of branch channels branching from the main channel, and a common air exhaust channel with which the plurality of branch channels merge at terminal ends, and dispensing fluid flowing down in the main channel sequentially to the plurality of branch channels from an upstream side of the main channel, wherein
the main channel includes first in-channel resistant parts arranged respectively in proximity to and on a downstream side of branching positions of the plurality of branch channels, the plurality of branch channels respectively include chamber region parts increased in channel cross-sectional area between the branching positions in the main channel and merging positions in the air exhaust channel, the air exhaust channel includes second in-channel resistant parts each arranged in proximity to one of the merging positions of the plurality of branch channels, and on a side of a merging position of a neighboring one of the plurality of branch channels with respect to the one of the merging positions as a center, and the first in-channel resistant parts and the second in-channel resistance parts respectively reduce channel cross-sectional areas of the main channel and the air exhaust channel and thus temporarily inhibit supplied fluid from flowing down by surface tension, and the respective cross-sectional areas are adjusted so that a first surface tension disruption pressure for releasing fluid from temporary inhibition of flowing down by each of the first in-channel resistant parts is greater than pressure generated by channel resistance against fluid flowing from a corresponding one of the branching positions to a corresponding one of the second in-channel resistant parts, and so that a second surface tension disruption pressure for releasing fluid from temporary inhibition of flowing down by each of the second in-channel resistant parts is greater than a sum of the first surface tension disruption pressure, pressure generated by channel resistance against fluid flowing from a corresponding one of the first in-channel resistant parts to a subsequent one of the first in-channel resistant parts, and pressure generated by channel resistance against fluid flowing from a subsequent one of the branching positions to a subsequent one of the second in-channel resistant parts.

2 . The fluid dispensing device according to claim 1 , wherein the first in-channel resistant parts and the second in-channel resistant parts reduce channel cross-sectional area by decreasing only widths of the main channel and the air exhaust channel, respectively, and thus temporarily inhibit supplied fluid from flowing down by surface tension.

3 . The fluid dispensing device according to claim 2 , wherein each of the first in-channel resistant parts and the second in-channel resistant parts comprises one or two projections formed by bulging one or both channel inner side walls toward an opposing inner side wall, or an obstacle arranged in the main channel or the air exhaust channel.

4 . The fluid dispensing device according to claim 3 , wherein each of the first in-channel resistant parts and the second in-channel resistant parts obtains a desired cross-sectional area by controlling a gap between an end surface of the one projection or the obstacle and a channel inner side wall opposing to the end surface, or a gap between both end surfaces of the two projections when formed by bulging both the inner side walls.

5 . The fluid dispensing device according to claim 4 , wherein each of the main channel and the air exhaust channel has a rectangular cross section having opposing wall surfaces, and each of the first in-channel resistant parts and the second in-channel resistant parts obtains a rectangular channel cross section by arranging the end surface of the one or two projections or the obstacle in parallel to the channel inner side wall.

6 . The fluid dispensing device according to claim 1 , wherein each of the second in-channel resistant parts comprises a plurality of parts for forming a reduced cross section.

7 . The fluid dispensing device according to claim 1 , wherein the plurality of branch channels branch from the main channel alternately on both sides of the main channel.

8 . The fluid dispensing device according to claim 1 , wherein the main channel and the air exhaust channel are arranged so as to allow fluid to flow down in concentric arcs, and the plurality of branch channels are arranged radially between the main channel and the air exhaust channel.

9 . A microfluidic device including a plurality of microchannels constituting the fluid dispensing device according to claim 1 in a microchannel chip,
the microfluidic device comprising the main channel, the plurality of branch channels and the air exhaust channel constituting the fluid dispensing device, a microchannel part for supplying fluid to the main channel, a fluid inlet port for introducing fluid into the microchannel part, reaction chambers arranged respectively in the chamber region parts formed in the plurality of branch channels, and outlet ports respectively connected to terminal ends of the main channel and the plurality of branch channels and forming openings at the terminal ends.

10 . The microfluidic device according to claim 9 , wherein each of the second in-channel resistant parts comprises a plurality of parts for forming a reduced cross section.

11 . The microfluidic device according to claim 9 , wherein the plurality of branch channels branch from the main channel alternately on both sides of the main channel.

12 . The microfluidic device according to claim 9 , wherein the main channel and the air exhaust channel are arranged so as to allow fluid to flow down in concentric arcs, and the plurality of branch channels are arranged radially between the main channel and the air exhaust channel.

13 . A chip for inspection including a plurality of microchannels constituting the fluid dispensing device according to claim 1 in a microchannel chip,
the chip for inspection comprising the main channel, the plurality of channels, and the air exhaust channel constituting the fluid dispensing device, a microchannel part for supplying fluid to the main channel, a fluid inlet port for introducing fluid into the microchannel part, reaction chambers arranged in the chamber region parts formed in the plurality of branch channels, and outlet ports respectively connected to terminal ends of the main channel and the plurality of branch channels and forming openings at the terminal ends, and
reagents being respectively fixed in the reaction chambers.

14 . The chip for inspection according to claim 13 , wherein each of the second in-channel resistant parts comprises a plurality of parts for forming a reduced cross section.

15 . The chip for inspection according to claim 13 , wherein the plurality of branch channels branch from the main channel alternately on both sides of the main channel.

16 . The chip for inspection according to claim 13 , wherein the main channel and the air exhaust channel are arranged so as to allow fluid to flow down in concentric arcs, and the plurality of branch channels are arranged radially between the main channel and the air exhaust channel.

Assignees

• National Univ Corporation Toyohashi Univ Of Technology

Inventors

• Shibata Takayuki
• Natsuhara Daigo
• Okamoto Shunya
• Nagai Moeto

Classifications

• B01L2400/0487

  fluid pressure, pneumatics · CPC title

• B01L2300/0864

  comprising only one inlet and multiple receiving wells, e.g. for separation, splitting · CPC title

• B01L2300/0816

  Cards, e.g. flat sample carriers usually with flow in two horizontal directions · CPC title

• B01L3/502723

  characterised by venting arrangements · CPC title

• B01L2200/0684

  Venting, avoiding backpressure, avoid gas bubbles · CPC title