A kind of screen printing electrode with porous membrane
Technical field
The utility model relates to field of electrochemical detection, more particularly to a kind of silk-screen printing electricity with porous membrane
Pole.
Background technique
Following background technique is used to help reader and understands the utility model, and is not construed as the prior art.
It is widely used using electrochemica biological sensor as the screen printing electrode of principle in detection field (POCT) immediately.It is raw
Liquid is managed, as contained the interested detection parameters of many clinical labororatories in blood, urine, sweat, saliva.Such as in blood
Glucose, cholesterol, glycosylated hemoglobin, blood ketone, the uric acid in urine, the lactic acid etc. in sweat.The testing principle of electrode is big
It is mostly by enzyme modification to working electrode corresponding to target analytes, the enzymatic reaction electric current by detection target analytes is real
Now to the fast quantitative analysis of target analytes.It, can when enzymatic reaction current signal relies only on the concentration of target analytes
Accurate quantitative analysis is carried out to target analytes.But in actually detected, other redox present in biological fluid
Active material can also participate in the generating process of current signal, cause just interference or negative interference to testing result.Therefore, in order to improve
The detection accuracy of electrode, it is crucial for improving the anti-interference of electrode.
Chinese patent CN102507670B is arranged one layer of jamproof reagent layer on the working electrode (s, when detection, to test sample
Product first penetrate reagent layer, and the ascorbic acid oxidase in reagent layer is reacted with the ascorbic acid in blood, to exclude ascorbic acid
Interference to uric acid signal.But the shortcomings that this method is: 1, the interfering substance type that can be excluded is limited, one layer of reagent
Layer is only used for excluding a kind of interfering substance;Even if 2, in order to exclude a variety of interfering substances, on the working electrode (s setting multilayer not
Congener reagent layer, interfering between one side reagent layer, enzyme layer thickness is excessive can be influenced on enzymatic activity, enzyme
Activity, which is lower, will cause interfering substance and excludes incomplete, and on the other hand, sample to be tested needs to get to bottom through multilayer reagent layer
Layer makes target analytes generate electric signal, causes the extension of testing time to a certain extent.In addition, macromolecular complex confrontation sample
The influence of detection accuracy also can not be ignored, for example, when carrying out quantitative analysis to the substance in blood, haemocyte is to detection accuracy
Influence, therefore test in also need to exclude influence of the macromolecular substances (such as haemocyte) to test.
Utility model content
The purpose of this utility model is to provide one kind can exclude a variety of chaff interferents influences, improves having for detection efficiency
The screen printing electrode of porous membrane.
A kind of screen printing electrode with porous membrane, including insulating substrate and electrode, insulating substrate are equipped with and are used for
Sample to be tested is guided to the diversion trench of electrode, diversion trench has sample suction end mouth, it is characterised in that: is arranged in diversion trench multiple
Microballoon.Multiple microballoons exclusive PCR substance by way of physical filtering.
Further, microballoon is made of polystyrene or silica.
Further, the partial size of microballoon is 1~500 μm.
Further, microballoon is solid construction either porous structure.
Further, electrode includes working electrode, and microballoon is located at sample suction end mouth between working electrode.
Biological chemical reagent
Biological chemical reagent can react with interfering substance, so that interfering substance be removed from sample to be tested.
Further, microsphere surface is modified with biological chemical reagent, and biological chemical reagent is enzyme corresponding with interfering substance.
Preferably, the method for modified biological chemical reagent is absorption, crosslinking, covalent bond.
Further, the biological chemical reagent is glucose oxidase, ascorbic acid oxidase, mutarotase, glucose
Dehydrogenase, lactate oxidase, urate oxidase, cholesteryl esterase, cholesterol oxidase, phosphatidase, aminoacidase, horseradish peroxide
Any one or more of enzymes such as compound enzyme, beta-hydroxybutyric dehydrogenase.
Further, each microballoon has a kind of biological chemical reagent, the biological chemical reagents of all microballoons there are two types of or
It is a variety of;Alternatively, each microballoon has two or more biological chemical reagents, the biochemistry examination having the same of all microballoons
Agent.
Filtering area
Filtering area is the region in diversion trench, where microballoon.
Further, multiple filtering areas are equipped in diversion trench, filtering area avoids electrode setting, and all microballoons are respectively positioned on filtering
In area.Preferably, the microballoon quantity in each filtering area is equal, alternatively, the microballoon quantity in filtering area is along sample to be tested water conservancy diversion
Direction successively decrease.The difference of microballoon quantity in two neighboring filtering area can be 10,20,30,50 ... each filtering areas can be with
It is linear or curved shape.
Preferably, filtering area is linear, the axis and diversion trench median perpendicular of filtering area.
Further, the both ends of filtering area are connect with the two sidewalls of diversion trench respectively, multiple filtering area interval settings;Or
Person, one end of filtering area and the side wall of diversion trench connect, the other end of filtering area is free end, and adjacent two filtering area staggeredly divides
Cloth.Preferably, filtering area free end is flushed with adjacent two filtering area free end, alternatively, filtering area free end is located at adjacent two mistake
It filters between area.
Preferably, when filtering area has free end, multiple filtering area interval settings.
Further, multiple filtering areas equidistantly arrange;Alternatively, the distance between adjacent two filtering area is led along sample to be tested
Successively decrease in the direction of stream.
Further, the microballoon quantity of multiple filtering areas is equal, alternatively, the microballoon quantity of multiple filtering areas is along sample to be tested
Successively decrease in the direction of water conservancy diversion.
Arrangement of microspheres
Sample to be tested is heavily dependent on by the elimination factor etc. of interfering substance in the speed of filtering area, sample to be tested
The partial size and arrangement mode of microballoon.
Further, filtering area stays district's groups at the area Kong Liu is located on microballoon area, and microballoon fills up in area by microballoon area and sky
Microballoon.
Further, microballoon has multilayer, and the partial size of microballoon is definite value;Alternatively, every layer of microballoon partial size having the same, upper one
The partial size of layer microballoon is less than the partial size of next layer of microballoon.The partial size of upper one layer of microballoon is less than the partial size of next layer of microballoon, that is,
It says, microballoon stacking in a manner of " up-small and down-big ".
Porous membrane
Further, filtering area includes porous membrane, and porous membrane and water conservancy diversion groove sidewall surround the mistake for accommodating microballoon
Filter area.Preferably, the pore size on porous membrane is less than the partial size of microballoon.
Further, the both ends of porous membrane respectively with diversion trench two sidewalls be tightly connected, adjacent two porous membrane with lead
Chute two sidewalls surround filtering area.
Further, porous membrane is tabular or bent plate shape.
Further, parallel between all porous membranes.
Further, it is equidistantly arranged between multiple filtering areas.
Further, porous membrane is made of Nafion or cellulose acetate.
The utility model has the beneficial effects that
1, there are multiple microballoons, the gap between gap and microballoon and water conservancy diversion groove sidewall between multiple microballoons in diversion trench
Physical filtering can be carried out such as the haemocyte in blood to interfering substance.
2, microsphere surface, which is modified with, to react with anti-interference substance, the biochemistry to eliminate anti-interference substance
Reagent, confrontation interfering substance carry out chemical filtering;There is microballoon biggish specific surface area can modify more biochemistry examination
Agent;The biological chemical reagent of microsphere surface can there are many, and will not be interfered between a variety of biological chemical reagents, thus
A variety of interfering substances can be eliminated simultaneously.
3, the multiple filtering areas being spaced apart from each other of setting, microballoon are respectively positioned in filtering area in diversion trench, prevent arrangement of microspheres mistake
In it is close, result in blockage, to improve detection efficiency;In addition, the porous membrane of filtering area can carry out second to sample to be tested
Secondary physical filtering, moreover it is possible to obstruct microballoon and electrode, while prevent microballoon from going out filtering area by sample to be tested.
4, microballoon in filtering area using the way of stacking of " up-small and down-big " can be improved interfering substance removal effect and
Detection efficiency.
Detailed description of the invention
Fig. 1 is the schematic diagram of the screen printing electrode piece of the utility model one embodiment, wherein Fig. 1 a) it is plane
Figure, Fig. 1 b) it is perspective view.
Fig. 2 a) be the utility model one embodiment filtering area schematic diagram, Fig. 2 b) one embodiment another mistake
Filter the schematic diagram in area.
Fig. 3 a) be the utility model one embodiment microballoon stacking schematic diagram, Fig. 3 b) one embodiment another kind
The schematic diagram of microballoon stacking.
Fig. 4 a) be the utility model one embodiment microballoon stacking schematic diagram, Fig. 4 b) one embodiment another kind
The schematic diagram of microballoon stacking.
Fig. 5 a) be the utility model one embodiment filtering area schematic diagram, Fig. 5 b) one embodiment another mistake
Filter the schematic diagram in area.
Fig. 6 is the porous membrane schematic diagram of the utility model one embodiment.
Fig. 7 is the schematic diagram of the porous membrane position of the utility model one embodiment.
Fig. 8 is the curve graph (blood of uric acid in blood content and testing time that various embodiments of the utility model 1~3 measures
Uric acid content is 300 μm of olL in liquid-1)。
The uric acid in blood content and testing time that Fig. 9 various embodiments of the utility model 1, embodiment 4 and embodiment 5 measure
Curve graph (uric acid in blood content be 300 μm of olL-1)。
Specific embodiment
The detailed description of a step is carried out to the utility model combined with specific embodiments below.
Embodiment 1
A kind of screen printing electrode with porous membrane, such as Fig. 1 a) and Fig. 1 b) shown in, including insulating substrate 100, work
Make electrode 101, reference electrode 102, auxiliary electrode 103 and cover board 4, working electrode 101, reference electrode 102 and auxiliary electrode 103
It is set on insulating substrate 100, insulating substrate 100 is equipped with for sample to be tested to be guided to working electrode 101, reference respectively
The diversion trench 3 of electrode 102 and auxiliary electrode 103.101 one end of working electrode connect with working electrode terminal 201, working electrode
101 other end is connect with diversion trench 3;102 one end of reference electrode connect with reference electrode terminal 202, reference electrode 102
The other end is connect with diversion trench 3;103 one end of auxiliary electrode connect with auxiliary electrode terminal 203, the other end of auxiliary electrode 103
It is connect with diversion trench 3.Cover plate lid is on insulating substrate, and cover board is covered in hydrophilic film by insulating materials stickup and being made makes to lead
Chute forms capillary.Sample to be tested is sucked electrode test piece from sample suction end mouth 305 using capillarity and examined by diversion trench
It surveys.
Multiple solid microsphere 6 made of polystyrene are arranged in diversion trench 3.The partial size of microballoon is definite value.
In some embodiments, microballoon is made of silica.
In some embodiments, the partial size of microballoon is 1~500 μm.
In some embodiments, microballoon is porous structure.The microballoon opposing solid structure of porous structure has bigger ratio
Surface area, so that each microballoon can modify more biological chemical reagents.
Gap is formed between multiple microballoons and between microballoon and diversion trench.As long as the partial size of interfering substance in sample to be tested
Greater than the gap between gap, microballoon and the diversion trench between microballoon, when sample to be tested passes through diversion trench, interfering substance can
It is foreclosed by microballoon.That is, multiple microballoons in diversion trench are by way of physical filtering, exclusive PCR substance.Example
Such as, when sample to be tested is blood, the gap between multiple microballoons is less than the partial size of haemocyte in blood, can rise to haemocyte
Filtration prevents haemocyte to be guided to working electrode and auxiliary electrode with blood to be measured, influence testing result.
Microballoon is located at sample suction end mouth 303 between working electrode 101.As shown in Fig. 1 b), working electrode 101 and sample suction end
Diversion trench between mouthfuls 303 is divided by reference electrode 102 for first segment 301 and second segment 302, and microballoon is located at first segment 301 and the
Two section 302.In some embodiments, microballoon is located at first segment.
Biological chemical reagent
Microsphere surface is modified with biological chemical reagent, and biological chemical reagent is enzyme corresponding with interfering substance.In this implementation
In example, the method for modified biological chemical reagent is absorption.In some embodiments, the method for modified biological chemical reagent can be
Crosslinking, covalent bond.
For example, it when screen printing electrode test piece is used to detect the uric acid content in blood, repairs on the working electrode (s
Adorn urate oxidase, the upper ascorbic acid oxidase of microsphere surface absorption in diversion trench.When blood flows through diversion trench, on microballoon
Ascorbic acid oxidase make in blood ascorbic acid be oxidized destruction to achieve the purpose that eliminate interference with this.In addition, close row
The microballoon of column can filter out the macromoleculars such as haemocyte in blood.
Another example, Prussian blue (PB) is for H2O2Electroreduction have high sensitivity, thus be referred to as " artificial mistake
Oxide enzyme ".But PB selectivity and specificity are poor, can be catalyzed in blood such as uric acid, ascorbic acid many kinds of substance.When
When screen printing electrode test piece is used to test the content of Blood Cholesterol, cholesterol oxidase is modified on the working electrode (s,
Each microsphere surface adsorbs upper cholesterol esterase, ascorbic acid oxidase, uricase simultaneously in diversion trench.It is led when blood flows through
When chute, the cholesterol esterase on microballoon makes Blood Cholesterol ester be oxidized to free cholesterol to carry out subsequent catalysis,
Free cholesterol and cholesterol oxidation enzyme reaction generate hydrogen peroxide, and Prussian blue catalyzing hydrogen peroxide generates mediator, is used to
Detect signal.Ascorbic acid oxidase and uricase on microballoon exclude the interference of ascorbic acid and uric acid in blood.
In addition, compact arranged microballoon can filter out the macromoleculars such as haemocyte in blood.
In some embodiments, biological chemical reagent can be glucose oxidase, ascorbic acid oxidase, mutarotase,
It is glucose dehydrogenase, lactate oxidase, urate oxidase, cholesteryl esterase, cholesterol oxidase, phosphatidase, aminoacidase, peppery
Any one or more of enzymes such as root peroxidase, beta-hydroxybutyric dehydrogenase.
In some embodiments, each microballoon has a kind of biological chemical reagent, and the biological chemical reagent of all microballoons has
Two or more;Alternatively, each microballoon has two or more biological chemical reagents, all microballoons bioid having the same
Learn reagent.Each microballoon has two or more biological chemical reagents with a kind of each microballoon of biological chemical reagent, can be
Every kind of biological chemical reagent is covered each by the different surfaces of microballoon, that is to say, that the different piece of microsphere surface is covered with difference
The biological chemical reagent of type.In this way, microballoon can be used for excluding a variety of interfering substances, and different types of biochemistry is tried
It will not be interfered with each other between agent, the activity of enzyme will not be influenced because coating is too thick.
For target analytes, interfering maximum is often to be present in sample to be tested, can participate in current signal
The substance of generation.The electric signal that these interfering substances measure electrode generates overgauge or minus deviation.These interfering substance sizes
It is likely less than the size of target analytes, target analytes and chaff interferent can be removed simultaneously simultaneously with the method for physical filtering.
Alternatively, although interfering substance size is greater than the size of target analytes, the size of interfering substance still very little, with physics mistake
The mode of filter removes, the gap size very little needed to form, will greatly influence the water conservancy diversion of sample to be tested in this way.Therefore, these
Substance is often difficult to be removed with the method for physical filtering.Therefore, preferable mode is to be done using biological chemical reagent with these
It disturbs substance to chemically react, to remove interfering substance.
Filtering area
Microballoon can be full of microballoon, each microballoon and surrounding in diversion trench in compact arrangement, that is, diversion trench
Microballoon is in close contact.But in this case, the gap formed between microballoon is too small, too intensive, when sample to be tested is by leading
When chute, haemocyte is easy the gap between blocking microballoon, causes sample sharply to slow down by speed, influences detection efficiency.Cause
This, is arranged filtering area in diversion trench.Filtering area is the region in diversion trench, where microballoon.
It as shown in Fig. 2 a), is set in diversion trench 3 there are five filtering area 5, filtering area 5 avoids electrode setting, and all microballoons 6 are
In filtering area.
The both ends of each filtering area 5 are connect with the two sidewalls of diversion trench 3 respectively, are separated by between five filtering areas 5.Each mistake
The microballoon that partial size is 8 μm is filled up in filter area, as shown in Fig. 5 a).Cover board, filtering area and water conservancy diversion trench bottom are sequentially connected.Each mistake
The microballoon quantity filtered in area is equal.
Multiple filtering areas are parallel.Multiple filtering areas equidistantly arrange.Filtering area is linear, and filtering area is about diversion trench
Middle line is symmetrical.
In some embodiments, the microballoon quantity of filtering area is successively decreased along the direction of sample to be tested water conservancy diversion.Sample to be tested water conservancy diversion
Direction refer to sample to be tested from sample suction end mouth to the direction of each electrode.As the filtering area that sample to be tested passes through increases, to
Interfering substance in sample is reduced, and the amount of required biological chemical reagent is reduced, thus the quantity of corresponding microballoon can subtract
It is few.The difference of microballoon quantity in two neighboring filtering area can be 10,20,30,50 ...
In some embodiments, the distance between adjacent two filtering area successively decreases along the direction of sample to be tested water conservancy diversion.To test sample
When product have just enter into diversion trench, the distribution of filtering area more crypto set, as the interfering substance in sample to be tested is reduced, point of filtering area
Cloth density reduces, to accelerate water conservancy diversion speed.
In some embodiments, as shown in Fig. 2 b), each filtering area 5 is curved shape.It is parallel between multiple filtering areas 5.
Curve filtering area can increase the contact area of each filtering area and sample to be tested, so that it is dry so that each filtering area is removed
Disturb substance increase.
Embodiment 2
For the present embodiment in addition to filtering area shape, remaining structure and composition can be same as Example 1.
As shown in figure 3, one end of filtering area 5 is connect with the side wall of diversion trench 3, the other end of filtering area 5 is free end, phase
Adjacent two filtering areas 5 are interspersed.It is interspersed and refers to that the left end of a filtering area is connecting pin, two mistakes adjacent thereto
The right end for filtering area is connecting pin;Or the right end of a filtering area is connecting pin, the left end of two filtering areas adjacent thereto is
Connecting pin.Five interval of filtering area 5 settings.
As shown in Fig. 3 a), 5 free end of filtering area is flushed with adjacent two filtering areas, 5 free end.
In some embodiments, as shown in Fig. 3 b), filtering area free end is between adjacent two filtering area.
Filtering area is linear, the axis of filtering area and the median perpendicular of metallic channel.
In some embodiments, filtering area is curved shape.
It is parallel between all filtering areas.In some embodiments, the multiple filtering areas being connect with the same side wall of diversion trench
Between it is parallel, can be not parallel between the filtering area being connect with different lateral.
Multiple equidistantly arrangements of filtering area 5.Equidistant arrangement refers to the multiple filterings connecting with the same side wall of diversion trench
Area connecting pin equidistantly arranges.
Embodiment 3
For the present embodiment in addition to microballoon way of stacking is different, remaining structure and composition can be with 2 phase of embodiment 1 or embodiment
Together.
Arrangement of microspheres
Sample to be tested is heavily dependent on by the elimination factor etc. of interfering substance in the speed of filtering area, sample to be tested
The partial size and arrangement mode of microballoon.The partial size and arrangement mode of microballoon determine the size in gap between microballoon, microsphere surface product
Size etc..Therefore, the arrangement mode of microballoon is crucial for detection effect and detection efficiency.
As shown in Fig. 4 a), the microballoon 6 in filtering area 501 has three layers, and every layer of microballoon partial size having the same, upper one layer micro-
The partial size of ball is less than the partial size of next layer of microballoon.Diversion trench is upper close to the direction of cover board.
In some embodiments, the microballoon in filtering area can have multilayer.
The interfering substance that can be removed by way of physical filtering often has biggish volume and quality, to be measured
The bottom of diversion trench is deposited on during the water conservancy diversion of sample.The microspherulite diameter of filtering area bottom is larger, the biggish microballoon pair of partial size
Interfering substance carries out physical filtering, prevents the gap between gap, microballoon and the water conservancy diversion groove sidewall between microballoon larger by volume
Interfering substance blocking.And the microspherulite diameter of filter layer top layer is smaller, the lesser microballoon of partial size is carrying out chemistry to interfering substance
There is advantage in filtering.Because the partial size of microballoon is smaller, the specific surface area that the microballoon of same volume has is bigger, microsphere surface
The biological chemical reagent amount that can be carried is more, so that the contact area of interfering substance and biological chemical reagent is increased, it is right
The elimination of interfering substance is more abundant.Therefore, this " up-small and down-big " way of stacking can be improved the removal effect of interfering substance
Fruit and detection efficiency.
Embodiment 4
In the present embodiment in addition to the structure of filtering area is different, other structures and composition can be identical as Examples 1 to 3.
Such as Fig. 4 b) and Fig. 5 b) shown in, filtering area 5 is made of microballoon area 501 and the area Kong Liu 502, and the area Kong Liu 502 is located at micro-
On ball area 501, microballoon 6 is filled up in microballoon area 501.Microballoon in microballoon area carries out physical filtering and chemical mistake to interfering substance
It filters, sample to be tested is not due to hindering, accelerating water conservancy diversion rate in the area Kong Liu.
In some embodiments, the microballoon in microballoon area has multilayer, and the partial size of microballoon is definite value, as shown in Fig. 5 b);Alternatively,
Every layer of microballoon partial size having the same, the partial size of upper one layer of microballoon is less than the partial size of next layer of microballoon, as shown in Fig. 4 b).
Embodiment 5
For the present embodiment in addition to filtering area is equipped with porous membrane, remaining structure and composition can be identical as Examples 1 to 4.
Porous membrane
As shown in Figure 6 and Figure 7, each filtering area 5 includes porous membrane 7 and microballoon, and porous membrane is enclosed with water conservancy diversion groove sidewall
At the space for accommodating microballoon.701 size of hole of porous membrane is less than the partial size of microballoon.
The both ends of porous membrane 7 are connect with diversion trench two sidewalls 301 respectively, adjacent two porous membrane 7 and diversion trench two sides
Wall 301 surrounds filtering area.As shown in fig. 7, porous membrane 7 is tabular or bent plate shape.It is parallel between all porous membranes 7.It is more
Hole diaphragm is made of Nafion or cellulose acetate.
Sample to be tested can also carry out second of physical filtering by porous membrane before leaving the filtering area;Simultaneously because
Pore size on porous membrane is less than microspherulite diameter, therefore the porous membrane can prevent microballoon in sample to be tested by the mistake of water conservancy diversion
Filtering area is rushed out in journey.In addition, porous membrane can also be between microballoon and electrode for close to the filtering area of electrode
It is obstructed.The reason of being obstructed is, when the biological chemical reagent and interfering substance of microsphere surface react,
It is likely to generate interference electric current signal, if these interference electric current signals are conducted to working electrode and auxiliary electrode, instead
And interfering substance bring error can be increased.
Known uric acid in blood content to be measured is 300 μm of olL-1, the song of the uric acid content of each Examples 1 to 3 measured
The curve graph of line chart and testing time are as shown in Figure 8.Microballoon is filled up in the filtering area of each embodiment.Wherein 1. correspond to diversion trench
The inside not no electrode test piece of microballoon, 2. corresponding embodiment 1,3. 1 filtering area shape of corresponding embodiment and 3 arrangement of microspheres of embodiment
It combines, 4. corresponding embodiment 2, the 5. combination of corresponding embodiment 2 filtering area shape and 3 arrangement of microspheres of embodiment.It can from Fig. 8
It arrives, the filtering area shape of embodiment 2 can shorten detection time, and the arrangement of microspheres of embodiment 3 can shorten detection time and mention
High measurement accuracy.
Known uric acid in blood content to be measured is 300 μm of olL-1, each embodiment 1, embodiment 4 and the embodiment 5 that measure
Uric acid content curve graph and the curve graph of testing time it is as shown in Figure 9.In experiment, the filtering area that is all made of in embodiment 1
Shape.Wherein, 6. corresponding embodiment 1,7. the combination of corresponding embodiment 1 filtering area shape and 4 filtering section configuration of embodiment, 8. right
Answer the combination of embodiment 1 filtering area shape and 5 porous membrane of embodiment.It will be seen from figure 9 that the filtering section configuration of embodiment 4
Detection time can be shortened, the porous membrane of embodiment 5 can be improved detection accuracy.
Content described in this specification embodiment is only an enumeration of the implementation forms of the utility model concept, this is practical new
The protection scope of type should not be construed as being limited to the specific forms stated in the embodiments, the protection scope of the utility model also and
In those skilled in the art according to the utility model design it is conceivable that equivalent technologies mean.