U.S. patent application number 11/462988 was filed with the patent office on 2007-06-21 for matrix electrode-controlling device and digital platform using the same.
This patent application is currently assigned to INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE. Invention is credited to Chun-Han Wang.
Application Number | 20070138016 11/462988 |
Document ID | / |
Family ID | 38172175 |
Filed Date | 2007-06-21 |
United States Patent
Application |
20070138016 |
Kind Code |
A1 |
Wang; Chun-Han |
June 21, 2007 |
MATRIX ELECTRODE-CONTROLLING DEVICE AND DIGITAL PLATFORM USING THE
SAME
Abstract
A matrix electrode-controlling device for driving a droplet
includes a substrate, a dielectric layer positioned on the
substrate, a plurality of control electrodes positioned in the
dielectric layer in a matrix manner, and a ground electrode
positioned at a predetermined position around the control
electrodes without generating electromagnetic shielding effect. The
control electrodes in the same row are electrically connected to
form a plurality of lateral controlling rows and the control
electrodes in the same column are electrically connected to form a
plurality of longitudinal controlling columns. The droplet is
driven to move on or above the dielectric layer by biasing the
ground electrode to the ground voltage and applying a predetermined
voltage to one of the controlling rows and/or to one of the
controlling columns to undergo the predetermined assaying
operation.
Inventors: |
Wang; Chun-Han; (Kaohsiung
City, TW) |
Correspondence
Address: |
EGBERT LAW OFFICES
412 MAIN STREET, 7TH FLOOR
HOUSTON
TX
77002
US
|
Assignee: |
INDUSTRIAL TECHNOLOGY RESEARCH
INSTITUTE
Judung Township
TW
|
Family ID: |
38172175 |
Appl. No.: |
11/462988 |
Filed: |
August 7, 2006 |
Current U.S.
Class: |
204/600 |
Current CPC
Class: |
B01L 2400/0427 20130101;
B01L 2200/12 20130101; B01L 2300/0819 20130101; F04B 19/006
20130101; B01L 2400/0415 20130101; B01L 3/502792 20130101; B01L
2300/089 20130101 |
Class at
Publication: |
204/600 |
International
Class: |
G01N 27/00 20060101
G01N027/00; C02F 1/40 20060101 C02F001/40; C02F 11/00 20060101
C02F011/00; C25B 11/00 20060101 C25B011/00; C25B 13/00 20060101
C25B013/00; C25B 9/00 20060101 C25B009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 21, 2005 |
TW |
094145456 |
Claims
1. A matrix electrode-controlling device for driving a droplet, the
device comprising: a substrate; a dielectric layer positioned on
said substrate; a plurality of control electrodes positioned in
said dielectric layer in a matrix manner, said control electrodes
forming a plurality of controlling rows and a plurality of
controlling columns; and a ground electrode positioned at a
predetermined position around said control electrodes without
generating electromagnetic shielding effect; wherein the droplet is
driven to move on or above said dielectric layer by applying a
predetermined voltage to one of the controlling rows and/or to one
of the controlling columns.
2. The matrix electrode-controlling device for driving a droplet of
claim 1, wherein the dielectric layer has a rough surface.
3. The matrix electrode-controlling device for driving a droplet of
claim 1, wherein the control electrodes have an edge of a
sawtoothed or irregular shape.
4. The matrix electrode-controlling device for driving a droplet of
claim 1, further comprising: a hydrophobic layer positioned on said
dielectric layer, said droplet being moved on a surface of said
hydrophobic layer.
5. The matrix electrode-controlling device for driving a droplet of
claim 1, wherein the control electrodes in the same row are
electrically connected in an alternate manner to form the
controlling rows, and the control electrodes in the same column are
electrically connected in an alternate manner to form the
controlling columns.
6. The matrix electrode-controlling device for driving a droplet of
claim 1, further comprising: a circuit layer positioned on said
substrate, said circuit layer comprising a plurality of connecting
wires electrically connected to the control electrodes of the
controlling rows and the control electrodes of the controlling
columns, applying the predetermined voltage thereto.
7. The matrix electrode-controlling device for driving a droplet of
claim 6, wherein the connecting wires of the circuit layer connect
the control electrodes substantially in a vertical manner.
8. A matrix electrode-controlling device for driving a droplet,
comprising: a substrate; a dielectric layer positioned on said
substrate; a plurality of control electrodes positioned inside said
dielectric layer in a matrix manner, each control electrode having
a first conductive region and a second conductive region, wherein
each first conductive region of the control electrodes in a same
row are electrically connected to form a plurality of controlling
rows, and wherein each second conductive region of the control
electrodes in a same column are electrically connected to form a
plurality of controlling columns; and a ground electrode positioned
at a predetermined position around the control electrodes without
generating electromagnetic shielding effect; wherein the droplet is
driven to move on or above the dielectric layer by applying a
predetermined voltage to one of the controlling rows and/or to one
of the controlling columns.
9. The matrix electrode-controlling device for driving a droplet of
claim 8, wherein the dielectric layer has a rough surface.
10. The matrix electrode-controlling device for driving a droplet
of claim 8, further comprising: a hydrophobic layer positioned on
said dielectric layer, said droplet being moved on a surface of
said hydrophobic layer.
11. The matrix electrode-controlling device for driving a droplet
of claim 8, further comprising: a circuit layer positioned on said
substrate, said circuit layer comprising a plurality of connecting
wires electrically connected to the control electrodes of the
controlling rows and the control electrodes of the controlling
columns for applying the predetermined voltage thereto.
12. The matrix electrode-controlling device for driving a droplet
of claim 11, wherein the connecting wires of the circuit layer
connect the control electrodes substantially in a vertical
manner.
13. The matrix electrode-controlling device for driving a droplet
of claim 8, wherein each of the first conductive regions and each
of the second conductive regions are positioned on the same
plane.
14. The matrix electrode-controlling device for driving a droplet
of claim 13, wherein each of the first conductive regions and each
of the second conductive regions substantially surround one
another.
15. The matrix electrode-controlling device for driving a droplet
of claim 8, wherein the control electrodes have an edge of a
sawtoothed or irregular shape.
16. A digital platform for assaying a fluid, comprising: a matrix
electrode-controlling device for driving a droplet as claimed in
claim 1; a probing device electrically connected to the matrix
electrode-controlling device; and a control unit electrically
connected to the matrix electrode-controlling device and the
probing device, wherein the control unit is configured to control
the droplet to undergo a digital operation via the matrix
electrode-controlling device, and to control the droplet to undergo
a digital probing process via the probing device.
17. The digital platform for assaying a fluid of claim 16, wherein
the control unit is a computer.
Description
RELATED U.S. APPLICATIONS
[0001] Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO MICROFICHE APPENDIX
[0003] Not applicable.
FIELD OF THE INVENTION
[0004] The present invention relates to a matrix
electrode-controlling device and a digital platform using the same,
and more particularly, to a matrix electrode-controlling device for
driving a droplet and a digital platform for assaying a fluid using
the same.
BACKGROUND OF THE INVENTION
[0005] Controlling a droplet under test is an important technique
for the biomedical assaying operation. To date, electrowetting is
used as the conventional technique, which uses top and bottom
electrodes in a sandwich structure to control the movement of the
droplet, as disclosed in U.S. Pat. No. 6,565,727. However, the
conventional technical faces a technical problem in that the
droplet is restricted in space between the top and the bottom
electrodes such that adding extra additives into the droplet under
test from the top side or the bottom side of the droplet during an
assaying process is quite difficult. In addition, the conventional
technique does not possess the ability of controlling the movements
of multiple droplets simultaneously, and therefore the conventional
technique is restricted from being applied to the processes of
assaying samples such as genes or protein chips.
[0006] Chip design using the electrowetting effect to drive the
droplet generally use the following two methods to apply a
predetermined voltage to the control electrodes:
[0007] Method 1: assigning connecting wires to each control
electrode, and applying voltage to the desired control electrode to
generate the electrowetting effect by directly applying the voltage
to the desired control electrode via the assigned connecting wire
(see: Pollack, M. G., Fair, R. B., and Shenderov, A. D.,
Electrowetting-based actuation of liquid droplets for microfluidic
applications, Appl. Phys. Lett. 77 (2000) 1725-1726).
[0008] Method 2: using the opto-electrowetting (OEW) technique, in
which connecting wires connecting the control electrodes are biased
to a predetermined voltage in advance, and an optically sensitive
material is positioned between the control electrodes and the
connecting wires such that the control electrode is not biased to
the predetermined voltage. A laser light irradiates on the optical
sensitive material to bias the predetermined voltage to certain
control electrodes to generate the driving force (see: Chiou, P.
Y., Chang, Z., and Wu, M. C., Light actuated microfluidic devices,
MEMS-03 (2003) 355-358).
[0009] Method 1 is a direct design, but requires a number of
connecting wires to connect each control electrode to the power
supply, and the circuit layer is quite complicated for a design
with a large number of control electrodes. Method 2 solves the
complicated circuit layout problem, but needs additional laser
sources, which make the entire system very large.
[0010] To solve the above problems, researchers try to incorporate
Method 1 and Method 2 to achieve two-dimensional driving ability of
the droplet (see: Fan, S. K., Hashi, C., and Kim, C. J.,
Manipulation of multiple droplet on N.times.M grid by
cross-reference EWOD driving scheme and pressure-contact package,
MEMS-03 (2003) 694-697). Nevertheless, this technique also faces
the same problem as Method 1 and Method 2 due to use of the
electrowetting on dielectric (EWOD) design, i.e., the top and
bottom electrodes in the sandwich structure restrict the space for
adding extra additives.
[0011] The inventor of the present invention recognizes the above
issue and provides a matrix electrode-controlling device using a
single side electrode architecture to reduce the required space
such that both the complicated circuit layout problem for a design
with a large number of control electrodes and the huge system issue
can be resolved, and some possible new applications can be
created.
BRIEF SUMMARY OF THE INVENTION
[0012] One aspect of the present invention provides a matrix
electrode-controlling device for driving a droplet and a digital
platform for assaying a fluid using the same, which can drive a
droplet to move so as to undergo a predetermined assaying
operation.
[0013] A matrix electrode-controlling device for driving a droplet
according to this aspect of the present invention comprises a
substrate, a dielectric layer positioned on the substrate, a
plurality of control electrodes positioned in the dielectric layer
in a matrix manner, and a ground electrode positioned at a
predetermined position around the control electrodes without
generating electromagnetic shielding effect. The control electrodes
in the same row are electrically connected to form a plurality of
lateral controlling rows. The control electrodes in the same column
are electrically connected to form a plurality of longitudinal
controlling columns. The droplet is driven to move on or above the
dielectric layer by biasing the ground electrode to the ground
voltage and applying a predetermined voltage to one of the
controlling rows and/or to one of the controlling columns to
undergo the predetermined assaying operation.
[0014] Another aspect of the present invention provides a matrix
electrode-controlling device for driving a droplet, and the matrix
electrode-controlling device comprises a substrate, a dielectric
layer positioned on the substrate, a plurality of control
electrodes positioned in the dielectric layer in a matrix manner,
and a ground electrode positioned at a predetermined position
around the control electrodes without generating electromagnetic
shielding effect. Each control electrode includes a first
conductive region and a second conductive region; the first
conductive regions of the control electrodes in the same row are
electrically connected to form a plurality of lateral controlling
rows, and the second conductive regions of the control electrodes
in the same column are electrically connected to form a plurality
of longitudinal controlling columns. The droplet is driven to move
on or above the dielectric layer by biasing the ground electrode to
the ground voltage and applying a predetermined voltage to one of
the controlling rows and/or to one of the controlling columns to
undergo the predetermined assaying operation.
[0015] A further aspect of the present invention provides a digital
platform for assaying a fluid, and the digital platform comprises a
matrix electrode-controlling device for driving a droplet, a
probing device electrically connected to the matrix
electrode-controlling device and a control unit electrically
connected to the matrix electrode-controlling device and the
probing device. The control unit is configured to control the
droplet to undergo a digital operation via the matrix
electrode-controlling device, and to control the droplet to undergo
a digital probing process via the probing device. Preferably, the
control unit is a computer.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0016] The objectives and advantages of the present invention will
become apparent upon reading the following description and upon
reference to the accompanying drawings.
[0017] FIG. 1 is a cross-sectional view of a diagram of a matrix
electrode-controlling device according to a first embodiment of the
present invention.
[0018] FIG. 2 shows plan view of the arrangement of control
electrodes of a matrix electrode-controlling device according to a
first embodiment of the present invention.
[0019] FIG. 3 shows a cross-sectional view of the movement of a
droplet driver by a matrix electrode-controlling device according
to a first embodiment of the present invention.
[0020] FIG. 4 is a plan view illustrating a matrix
electrode-controlling device according to a second embodiment of
the present invention.
[0021] FIG. 5 is another plan view illustrating a matrix
electrode-controlling device according to a third embodiment of the
present invention.
[0022] FIG. 6 illustrates a cross-sectional view of a circuit
layout for a circuit layer of connecting wires according to one
embodiment of the present invention.
[0023] FIG. 7a and FIG. 7b illustrate schematic views of control
electrodes according to one embodiment of the present
invention.
[0024] FIG. 8 illustrates a schematic view of digital platform for
assaying a fluid according to one embodiment of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0025] To solve the prior art problems, one embodiment of the
present invention arranges the control electrodes in a matrix
manner to simplify the circuit layout of the connecting wires and
connecting sites for the control electrodes. Particularly, the
control electrodes are connected in series in the lateral and the
longitudinal direction to simplify the circuit layout of the
connecting wires and connecting sites for the control electrodes of
the matrix electrode-controlling device.
[0026] For example, an electrode-controlling device having several
control electrodes positioned in an m.times.n matrix manner needs
m.times.n+1 (ground electrode) connecting wires and connecting
sites to the power source if each electrode is connected to a power
supply via an individual connecting wire. Obviously, the circuit
layout will be very complicated. In contrast, the embodiment of the
present invention needs only m+n+1 connecting wires and connecting
sites to the power source to connect m.times.n+1 control electrodes
to control the movement of the droplet, i.e., m connecting wires
for connecting the control electrodes in the same row, n connecting
wires for connecting the control electrodes in the same column, and
one connecting wire for the ground electrode. Consequently, the
circuit layout is dramatically simplified and the large scale
control electrodes platform for controlling the movement of the
droplet can be achieved.
[0027] FIG. 1 to FIG. 3 illustrate a matrix electrode-controlling
device 10 for driving a droplet 20 according to a first embodiment
of the present invention. FIG. 1 is a cross-sectional diagram of
the matrix electrode-controlling device 10, FIG. 2 shows the
arrangement of the control electrodes 105 of the matrix
electrode-controlling device 10, and FIG. 3 shows the movement of
the droplet 20 driven by the matrix electrode-controlling device
10. The matrix electrode-controlling device 10 comprises a
substrate 101, a dielectric layer 103 positioned on the substrate
101, a plurality of control electrodes 105 positioned in the
dielectric layer 103 in a matrix manner, and a ground electrode 107
positioned at a predetermined position around the control
electrodes 105 without generating electromagnetic shielding
effect.
[0028] The substrate 101 is preferably a glass substrate, a
semiconductor substrate such as silicon substrate or a printed
circuit board. The dielectric layer 103 can be made of silicon
oxide, silicon nitride, silicon oxynitride or photoresist.
Preferably, the dielectric layer 103 has a rough surface to
increase the contact angle of the droplet 20 on the rough surface
so as to increase the driving force. Particularly, the dielectric
layer 103 covers the substrate 101, the control electrodes 105 and
the ground electrode 107 such that the control electrodes 105 and
the ground electrode 107 are electrically isolated from each
other.
[0029] The control electrodes 105 and the ground electrode 107 are
positioned in the dielectric layer 103, and can be made of metal
such as gold, aluminum, silver or copper. In addition, the control
electrodes 105 may have an edge of a sawtoothed or irregular shape
(not shown in the drawing) to enhance the control ability of the
droplet 20 by adjacent control electrodes 105. The ground electrode
107 is preferably positioned around the control electrodes 105, and
at a different level from where the control electrodes 105 are
positioned such that the projection areas of the ground electrode
107 and the control electrodes 105 do not overlap each other,
thereby avoiding the electromagnetic shielding effect, which
reduces control of the movement of the droplet 20. A plurality of
connecting wires 109 are used to electrically connect the control
electrodes 105 and the ground electrode 107 such that the ground
electrode can be connected to a ground voltage and these control
electrodes 105 can be connected to a predetermined voltage.
[0030] FIG. 2 illustrates the matrix electrode-controlling device
10 having 5.times.5 control electrodes 105 according to one
embodiment of the present invention. The significant difference
between the prior art and the embodiment of the present invention
is that the control electrodes 105 of the matrix
electrode-controlling device 10 is arranged in a matrix manner and
forms a plurality of lateral controlling rows 30a, 30b, 30c, 30d,
and 30e, and a plurality of longitudinal controlling columns 40a,
40b, 40c, 40d, and 40e. Consequently, the matrix
electrode-controlling device 10 needs a total of 5+5+1=11
connecting wires 109 and connecting sites to connect a total of
5.times.5+1=26 control electrodes 105 plus one ground electrode
107. In contrast, the prior art needs a total of 26 connecting
wires and connecting sites to connect a total of 5.times.5+1=26
control electrodes. Obviously, the number of connecting wires 109
required for the embodiment of the present invention is
dramatically decreased from 26 down to 11.
[0031] To drive the droplet 20 to move on or above the dielectric
layer 103, the ground electrode 107 is biased to the ground
voltage, and a predetermined voltage is applied to the control
electrodes 105 of one of the controlling rows 30a, 30b, 30c, 30d,
and 30e, and/or to the control electrodes 105 of one of the
controlling columns 40a, 40b, 40c, 40d, and 40e, as shown in FIG.
1. Particularly, several droplets 20 can be driven to move on the
dielectric layer 103 in a two dimensional manner by applying the
predetermined voltage to the controlling rows 30a, 30b, 30c, 30d,
and 30e, and/or to one of the controlling columns 40a, 40b, 40c,
40d, and 40e in a certain sequence.
[0032] Referring to FIG. 3, a hydrophobic layer 102 made of
hydrophobic material such as Teflon (C.sub.2F.sub.4) can be
positioned on the dielectric layer 103 and the droplet 20 is moved
on the surface of the hydrophobic layer 102. The hydrophobic layer
102 can increase the contact angle of the droplet 20 and the
dielectric layer 103 to have a better driving control ability.
[0033] FIG. 4 illustrates a matrix electrode-controlling device 10'
for driving droplets 20a and 20b according to a second embodiment
of the present invention. In comparison to the matrix
electrode-controlling device 10 in FIG. 1 having all control
electrodes 105 in the same row/columns electrically connected to
form the controlling row/column, the matrix electrode-controlling
device 10' in FIG. 4 has the control electrodes 105 in the same row
electrically connected in an alternate manner to form several
lateral controlling rows 31a, 31b, 31c, 31d, and 31e, and the
control electrodes 105 in the same column electrically connected in
an alternate manner to form several longitudinal controlling
columns 41a, 41b, 41c, 41d, and 41e.
[0034] To drive the droplet 20a to move upward, the ground
electrode 107 is connected to the ground voltage, and a
predetermined voltage is applied to the control electrodes 105 of
the controlling rows 31a such that the electrowetting effect occurs
to generate driving forces on the droplet 20a as shown by the
arrows, while the droplet 20b on the controlling row 31d away from
the effective controlling row 31a does not move since there is no
electrowetting effect. Similarly, the ground electrode 107 is
connected to the ground voltage, and a predetermined voltage is
applied to the control electrodes 105 of the controlling column 41a
such that the electrowetting effect occurs to generate driving
forces on the droplet 20b to move the droplet 20b leftward as shown
by the arrows, while the droplet 20a on the controlling row 41d
away from the effective controlling row 41a does not move since
there is no electrowetting effect
[0035] FIG. 5 illustrates a matrix electrode-controlling device
10'' for driving droplets 20c, 20d and 20e according to a third
embodiment of the present invention. The control electrodes 105 are
arranged in a matrix manner, and each control electrode 105
includes a first conductive region 105a and a second conductive
region 105b. The plural first conductive regions 105a of the plural
control electrodes 105 in the same row are electrically connected
to form a plurality of lateral controlling rows 32a, 32b, 32c, 32d,
and 32e. Meanwhile, the plural second conductive regions 105b of
the plural control electrodes 105 in the same column are
electrically connected to form a plurality of longitudinal
controlling columns 42a, 42b, 42c, 42d, and 42e. The control
electrodes 105 in the same row/column are electrically connected
laterally/longitudinally to provide coordinated coverage of the
control electrodes 105 in the same row/column.
[0036] To drive the droplet 20c and the droplet 20e to move upward
as indicated by the arrow, the ground electrode 107 is connected to
the ground voltage, and a predetermined voltage is applied to the
controlling columns 32a such that the electrowetting effect occurs
at the first conductive region 105a of the controlling row 32a to
generate upward driving forces on the droplet 20c and the droplet
20d to move them upward as shown by the arrows, while the droplet
20e on the controlling row 32d away from the effective controlling
row 32a does not move since there is no electrowetting effect.
Similarly, the ground electrode 107 is connected to the ground
voltage, and a predetermined voltage is applied to the control
electrodes 105 of the controlling column 42a such that the
electrowetting effect occurs at the second conductive region 105b
of the controlling column 42a to generate leftward driving forces
on the droplet 20c and the droplet 20e to move them leftward as
shown by the arrows, while the droplet 20d on the controlling
column 42d away from the effective controlling row 42a does not
move since there is no electrowetting effect.
[0037] Likewise, the ground electrode 107 is connected to the
ground voltage, and a predetermined voltage is applied to the
control electrodes 105 of both the control row 32a and the
controlling column 42a such that the electrowetting effect occurs
at the first conductive region 105a of the controlling row 32a and
at the second conductive region 105b of the controlling column 42a
to generate upward and leftward driving forces on the droplet 20c
to move the droplet 20c upward and leftward as shown by the arrows.
The droplet can be optionally moved upward, downward, leftward or
rightward to a desired position by applying the predetermined
voltage to the controlling rows 32a, 32b, 32c, 32d, and 32e, and/or
to one of the controlling columns 42a, 42b, 42c, 42d, and 42e in a
certain sequence. Particularly, the matrix electrode-controlling
device 10'' allows for the simultaneous driving of multiple
droplets by proper application of predetermined voltage to the
controlling rows and/or columns.
[0038] The matrix electrode-controlling device 10'' shown in FIG. 4
uses an alternate design, and the matrix electrode-controlling
device 10'' shown in FIG. 5 uses a dual conductive regions design.
Since each control electrode 105 needs lateral and longitudinal
connecting wires 109 to form electric connecting, there are
intersections at the lateral connecting wires 109 and the
longitudinal connecting wires 109, which are perpendicular to each
other. Furthermore, each connecting wire 109 needs to pass over one
control electrode to connect two staggered control electrodes
separated by a central control electrode. Obviously, the layout of
the connecting wires 109 is quite complicated, and the present
invention provides a new architecture for the circuit layout of the
connecting wires 109.
[0039] FIG. 6 illustrates a circuit layout for the connecting wires
109 according to one embodiment of the present invention. The
present invention provides dual layer connecting wires to solve the
above problems. Taking the matrix electrode-controlling device 10'
in FIG. 4 for example, a circuit layer 106 is positioned between
the control electrodes 105 and the substrate 101, and the circuit
layer 106 comprises a plurality of connecting wires 109
electrically connected to the control electrodes 105 of the
controlling rows/columns for applying the predetermined voltage
thereto. Furthermore, a plurality of vertical connecting wires 108
are used to electrically connect the control electrodes 105 and the
horizontal connecting wires 109 of the circuit layer 106 such that
the connecting wires 109 can pass over one control electrode to
connect two control electrodes on either side of the passed-over
electrode. Consequently, the connecting wires 109 of the circuit
layer 106 can connect the control electrodes 105 laterally and
longitudinal without the occurrence of short circuit at the
intersection.
[0040] The matrix electrode-controlling device 10'' shown in FIG. 5
uses a dual conductive regions design, in which each control
electrode 105 includes the laterally-connected first conductive
regions 105a and the longitudinally-connected second conductive
regions 105b, and each control electrode 105 is preferably
omni-directional such that the droplets 20c, 20d and 20e can be
optionally moved upward, downward, leftward or rightward. In
addition, the first conductive regions 105a and the second
conductive regions 105b are preferably positioned on the same
plane.
[0041] FIG. 7a and FIG. 7b illustrate the control electrodes 105
according to one embodiment of the present invention. Each control
electrode 105 includes the two conductive regions 105a and 105b
electrically isolated from each other. Particularly, the first
conductive regions 105a and the second conductive regions 105b
substantially surround one another to form two electrically
isolated conductive regions, i.e., one inner conductive region and
one outer conductive region, and the inner conductive regions
extends to the peripheral of the control electrodes 105 such that
the perimeter lengths of the droplet in the two conductive regions
are substantially equivalent. Consequently, the droplet on the
control electrodes 105 contacts both of the two conductive regions
105a and 105b of the adjacent control electrodes 105, and the
control ability of the driving force on the droplet is improved to
move the droplet upward, downward, to the left or right more
smoothly.
[0042] FIG. 8 illustrates a digital platform 20 for assaying a
fluid according to one embodiment of the present invention, wherein
the digital platform 20 incorporates the above matrix electrode
control device for undergoing a digital operation or a digital
probing process. The digital platform 20 comprises a matrix
electrode-controlling device 10 for driving a droplet, a probing
device 21 electrically connected to the matrix
electrode-controlling device 10 and a control unit 22 electrically
connected to the matrix electrode-controlling device 10 and the
probing device 21. The matrix electrode-controlling device 10 can
be any one as described above for controlling the digital operation
of the droplet. The control unit 22 is preferably a computer
configured to control the droplet to undergo the digital operation
via the matrix electrode-controlling device 10, and to control the
droplet to undergo a digital probing process via the probing device
21. In addition, the digital platform 20 can further comprise
sensors or meters such as pH meters, which serve as personal
medical assistants.
[0043] The above-described embodiments of the present invention are
intended to be illustrative only. Numerous alternative embodiments
may be devised by those skilled in the art without departing from
the scope of the following claims.
* * * * *