Unlock instant, AI-driven research and patent intelligence for your innovation.

Microfluidic device and analyzing device using the same

a microfluidic device and analyzing device technology, applied in the field of microfluidic devices, can solve the problems of inability of conventional micropump or conventional micromixer to operate with liquids having the concentration of physiological saline that is important in the medical or biological field, high manufacturing cost, and large dead volume, and achieves superior performance, simple structure, and sufficient performance.

Inactive Publication Date: 2008-10-02
FLUID
View PDF3 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0015]According to a method of using AC electrodes which is superior in having a simple structure, the microfluidic device provided by the present invention realizes a micropump or a micromixer that exhibits sufficient performance even in a liquid having a high electrical conductivity, such as a physiological saline in which the conventional device does not operate.
[0017]Additionally, the micromixer of the present invention can operate even in a state in which a flow in the direction of the flow path is stopped. In the flow-stopped state, mixing in an extremely short distance that corresponds to the size (about four times as long as the width of the flow path) of two generated eddies can be continuously performed for an arbitrary time, and high-performance mixing in which the amount of samples consumed is small can be achieved.

Problems solved by technology

According to a mechanical or hydrodynamic method, the structure of the inside of a flow path is complex so as to easily cause clogging, and manufacturing costs are high, and the dead volume is great.
Additionally, although an electrical method is simple, the conventional micropump or the conventional micromixer is incapable of operating with a liquid having the concentration of a physiological saline that is important in the medical or biological field.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Microfluidic device and analyzing device using the same
  • Microfluidic device and analyzing device using the same
  • Microfluidic device and analyzing device using the same

Examples

Experimental program
Comparison scheme
Effect test

embodiment 1

[0038]First, a description will be given of a flow of a microfluid generated by action from AC electrodes. An electrothermal effect shown in Non-Patent Document 2 or a method of using the phenomenon of an AC electro-osmotic flow shown in Patent Document 3 is known as an electrical method of allowing a fluid to run in a micro-sized space.

[0039]FIG. 1 is a partially enlarged view of a conventional microfluidic device. The conventional microfluidic device is made up of a substrate 100, a pair of electrodes 40, an AC power 31, and sidewalls 18 forming a micro-sized flow path. The present inventors performed experiments using the conventional microfluidic device structured as shown in FIG. 1 in which the pair of electrodes 40 being in contact with the micro-sized flow path exist in a horizontally oriented plane. In the experiments, saline solutions differing in electrical conductivity (substantially proportional to its concentration) were used, and an AC voltage of 5 MHz was applied. In ...

embodiment 2

[0044]FIG. 6 is an enlarged view of a micromixer of the present invention. The present inventors further performed an experiment using a device structured so that a flow path extending in the horizontal direction intersects the pair of electrodes 40 arranged in the vertical direction as shown in FIG. 6. As a result, the present inventors found that two eddies between which an electrode-to-electrode gap lies occur.

[0045]FIG. 7 is an elevational view of a microfluidic device provided with the micromixer. The present inventors performed an experiment as followed. A Y-shaped flow path having two inflow paths is produced as shown in FIG. 7, and a physiological saline is poured from a first inflow port 12, whereas a physiological saline containing fluorescent beads for experimental observation is poured from a second inflow port 13. The fluorescent beads in a laminar-flow state flowing near the lower wall surface in the flow path moved close to the upper wall surface, opposite to the lowe...

embodiment 3

[0054]FIG. 11 is a general view of an analytical instrument provided with the microfluidic device of the present invention. In this embodiment, an example is shown in which the present invention is applied especially for a platelet aggregation test by which a platelet clump size is measured, and the structure and the operation of the instrument will be described.

[0055]As a preprocessing step for inspection, a platelet sample of platelet-rich plasma (PRP) or platelet-poor plasma (PPP) is prepared from the blood which has been drawn from a subject and mixed into 3.8% citric-acid solution, and is incubated at 37° C. equal to the body temperature in a sample reservoir (not shown). On the other hand, 0.3 μM epinephrine is produced as a platelet-aggregating agent, and is set in a reservoir for the aggregating agent provided at a liquid supply pump 16.

[0056]The plasma of the incubated platelet sample is replaced with a physiological saline, and then a small amount of the sample is dropped ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The conventional micropump and the conventional micromixer have the following problems. In a mechanical or hydrodynamic method, the structure of the inside of a flow path is complex so as to easily cause clogging, and manufacturing cost is high, and dead volume is large. Additionally, in an electrical method, the conventional micropump or the conventional micromixer was incapable of operating with a liquid having the concentration of a physiological saline that is important in the medical or biological field although the structure of the flow path is simple. These problems are solved by applying an AC voltage to a pair of electrodes in which an electrode-to-electrode gap between the pair of electrodes is vertically arranged and by generating the flow of a fluid in the direction opposite to gravity along the electrode-to-electrode gap. A micropump (43, 44) can be realized especially by forming a micro-sized flow path (11) in the vertical direction along the electrode-to-electrode gap, and a micromixer (41) can be realized by forming a micro-sized flow path (11) in the horizontal direction to cross at right angle to the electrode-to-electrode gap.

Description

BACKGROUND ART[0001]1. Technical Field[0002]This invention relates to a microfluidic device that has micro-sized flow paths dug into a glass substrate or a plastic substrate so as to make an analysis or produce a reaction in the flow paths by use of small amounts of samples and, more specifically, to a micropump that generates a flow in the direction of a flow-path axis while driving liquids in flow paths and to a micromixer that stirs and mixes liquids together while generating a swirling flow. Additionally, this invention relates to an analytical instrument that uses liquid or a particulate material flowing in liquids as a sample and that measures progress information about reactions to a reagent or collects reaction products.[0003]2. Description of the Related Art[0004]In recent years, to reduce the amount of samples and save process steps, a reactor or an analysis method that uses a microfluidic device widely has spread. An electro-osmotic flow or a pressure flow is widely used ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): B01J19/08
CPCB01F13/0076B01L3/5027B01L2300/0887B01L2400/0415F04B19/006B01L2300/088B01F33/3031
Inventor HIRAHARA, SHUZOTSURUTA, TOMOYUKIMINAMITANI, HARUYUKI
Owner FLUID