CN209803082U

CN209803082U - Analysis device for liquid samples

Info

Publication number: CN209803082U
Application number: CN201821716386.6U
Authority: CN
Inventors: J·P·埃斯基韦尔·博霍克斯; M·N·萨贝德·比斯卡拉; S·加索·庞斯
Original assignee: Catalonia Institute Of Advanced Studies; Fairingham Ltd; SPANISH NATIONAL RESEARCH COUNCIL
Current assignee: Catalonia Institute Of Advanced Studies; Fairingham Ltd; SPANISH NATIONAL RESEARCH COUNCIL
Priority date: 2017-10-23
Filing date: 2018-10-22
Publication date: 2019-12-17
Anticipated expiration: 2028-10-22
Also published as: ES1220194U; DE202018105846U1; KR20190001028U; KR200497971Y1; ES1220194Y

Abstract

An analysis device for a liquid sample, comprising: a microfluidic analytical channel made of wicking material having sufficient porosity to allow capillary flow of at least one liquid sample suitable for generating an electric current; at least one absorbent-receiving region coupled to the microfluidic analytical channel; at least one collection absorbent region coupled to the microfluidic analysis channel; a cathode region coupled to the microfluidic analytical channel; an anode region coupled to the microfluidic analysis channel; and at least one detection zone having a sensor, wherein each absorbent-receiving region and each absorbent-collecting region are coupled to the microfluidic analysis channel such that when a fluid suitable for generating an electrical current is deposited in the absorbent-receiving region, the fluid flows through the microfluidic analysis channel by capillary action to the absorbent-collecting region and is absorbed at the absorbent-collecting region, and wherein the sensor interacts with the sample as it flows through the microfluidic analysis channel by capillary action.

Description

Analysis device for liquid samples

Technical Field

The utility model discloses relate to the analytical equipment field generally. In particular, the present invention relates to an analysis device for liquid samples. Although the sample to be analyzed is preferably a liquid (which may contain suspended particles), the present invention may also be used to analyze gaseous samples or colloids.

background

A fuel cell is a device that converts the chemical energy of a fuel into electrical energy, which conversion occurs whenever the fuel is fed into the cell. These devices have been developed over a decade and recently have found opportunities for their exploitation in, for example, medical applications.

Fuel cells differ from conventional cells in that: fuel cells allow for the continuous replenishment of consumed reagents, i.e., the generation of current from an external source of fuel and oxygen, as opposed to the limited capacity of the energy reserve involved in the cell. In addition, the electrodes in the cell react and change according to the way they are loaded or unloaded, while the electrodes in the fuel cell are catalytic and relatively stable. In addition, conventional batteries consume solid reactants, and once the reactants are depleted, these batteries must either be discarded or recharged with current. Typically in a fuel cell, the reagents flow internally and the reaction products flow externally. Typically, this flow of reactants is achieved by using, for example, an external pump, which may complicate and expensive the construction of the fuel cell.

For example, U.S.2009092882a1(Kjeang e. et al) discloses a microfluidic fuel cell structure with flow-through electrodes. The anode electrode and the cathode electrode are porous and include a network of interstitial pores. A dummy insulator is located in the electrolyte bath between the electrodes. The dummy insulator is composed of a co-laminar flow of electrolyte. The inlet directs substantially all of the liquid reactant stream through the porous electrode. The disadvantages of this configuration are: some means (e.g., an external pump) is required to move the liquid reagent through the inlet of the fuel cell to operate.

More recently, it has been discovered that the integration of micro direct methanol fuel cells can successfully provide pumping and current to microfluidic platforms [ JP establishment et al, fuel cell powered microfluidic platforms for lab-on-a-chip applications, 12, 74-79. The electrochemical reaction occurring in the fuel cell produces CO₂It is generally considered to be a residue that does not have any use. However, in this case, CO₂build-up occurs and is used to pump fluid into the microfluidic platform. Thus, pumping of the fluid (which may be a reagent for the fuel cell) is achieved without the need for an external pump, but a methanol fuel cell must be used for this purpose. Therefore, in this case, the configuration obtained is also complex and expensive. In addition, the use of a first fuel cell to form the reagent flow of a second fuel cell can complicate the system.

US2012288961 discloses a capillary-based device that utilizes flow metering and/or volumetric metering features on a porous membrane to perform microfluidic analysis.

however, none of the cited prior art discloses an analysis device providing both analysis and detection functions comprising a single microfluidic analysis channel.

Disclosure of Invention

Embodiments of the present invention provide an analytical device for liquid samples, preferably biological samples, such as blood, urine, sweat, saliva, tears, semen, milk, juice, wine, water, etc., comprising a microfluidic analytical channel made of wicking material(s) having sufficient porosity to allow capillary flow of at least one liquid sample suitable for generating an electric current; a receiving absorbent region coupled to the microfluidic analysis channel; a collection absorbent region coupled to the microfluidic analysis channel; a cathode region formed by at least one cathode coupled to the microfluidic analytical channel; an anode region formed by at least one anode coupled to the microfluidic analytical channel; and a detection zone comprising a sensor connected to the microfluidic analytical channel.

In the proposed analysis device, the absorbent receiving and collecting regions are connected to the microfluidic analysis channel such that when a liquid sample is deposited in the absorbent receiving region, the liquid sample flows through the microfluidic analysis channel by capillary action to the absorbent collecting region where it is absorbed.

In addition, the sensors of the detection zone interact with the liquid sample to be tested or analyzed as the sample flows through the microfluidic analytical channel by capillary action.

The proposed analysis device allows to reduce the volume of liquid sample required for generating and performing an analysis on the basis of having only a single microfluidic analysis channel. Furthermore, the design of the analysis device is simplified and only a small amount of material is required for manufacturing (compared to other analysis devices with different microfluidic channels). It also enables a simplification of the manufacturing process, thereby providing a higher cost-effectiveness to the analysis device.

The analysis device may comprise more than one absorbent receiving region coupled to the analysis microfluidic channel, in which case the different absorbent receiving regions may be completely independent, or they may be separate regions and located on the same physical support, also referred to as sub-regions in the present patent application.

Furthermore, the absorbent receiving and collecting regions may be located at different heights, which facilitates flow through the microfluidic analytical channel by capillary action.

In the present invention, the term "fluid suitable for generating an electric current" is understood to mean any fluid comprising at least one oxidizing or reducing substance, such that the fluid can interact with one of the cathode or the anode, thereby generating an electric current. Preferably, the fluid is a liquid, but it may contain suspended particles, or may be a gas or a colloid.

In addition to flowing properly to generate an electric current, the analysis device of the present invention can also introduce at least one electrolytic fluid into one receiving area coupled to at least one microfluidic analytical channel. Preferably, this electrolytic fluid is located in a receiving area different from the receiving area used to deposit any suitable fluid to generate the electrical current.

The utility model discloses an analytical equipment possesses following advantage: the flow of fluid (i.e., the flow of reactants) suitable for generating an electrical current is achieved by capillary action and/or diffusion, thereby eliminating the need for, for example, a pump or other mechanism to flow these reactants. In this regard, one key point of the analysis apparatus is that: once the microfluidic analytical channel is saturated, the absorption by the absorbent collecting region continues the flow by capillary action. The proposed analysis device is extremely simple and can be cheap, since the microfluidic analysis channel and the absorbent region can be manufactured from sufficient, cheap and biodegradable materials (e.g. fibre and cellulose based materials such as paper).

Preferably, the microfluidic analytical channel may consist essentially of a material independently selected from the group consisting of hydrophilic polymers, textile fibers, glass fibers, cellulose and nitrocellulose; it is particularly preferred that such materials are biodegradable.

Furthermore, the absorbent receiving and collecting regions are preferably made of a material selected from the group consisting of paper-based materials, fiber-based materials and nitrocellulose-based materials.

In any of the embodiments of the present invention, any cathode and any anode coupled to each microfluidic analytical channel may comprise a material selected primarily from the group consisting of noble metals, non-noble metals, enzymes, and bacteria. Where either electrode includes an enzyme or bacteria, the pH of the medium may be acidic, basic or neutral depending on the stability of the enzyme or bacteria at different phs. Preferably, the pH of the medium is one in which the metal, enzyme or bacteria present in either electrode have high stability and catalytic activity. To achieve this optimum pH, a suitable substance can be immobilized in the fuel cell.

Preferably, the assay device according to the present invention may be an assay strip, more preferably a strip referred to as a "lateral flow strip".

In one embodiment, the analysis device further comprises a conductive track (or first conductive track) to connect the anode and cathode regions of the analysis device with at least one electronic circuit. The electronic circuit is connected to the sensor comprised in said detection zone via a further conductive track (or a second conductive track). The electronic circuit is also connected to a display system in order to visualize the analysis results.

The electronic circuit and the display system may be integrated in a separate unit which is connectable to the analysis means via the above-mentioned conductive tracks.

the sensor included in the detection zone may be an electrochemical, optical, piezoelectric, magnetic, surface plasmon resonance, sonic or mass spectral sensor.

In one embodiment, the sensor may be formed of two separate parts, a first part serving as the detector and a second part serving as the transducer. Both parts may be comprised in the analysis device or, alternatively, the second part, which serves as a transducer, may be comprised in the separate unit.

In other embodiments of the present invention, each electrochemical sensor of the analysis device may be based on a carbon electrode. This type of material of the electrochemical sensor also contributes significantly to making the analysis device of the present invention more biodegradable.

In other embodiments of the present invention, the electronic circuit of the analysis device may be a silicon-based microelectronic circuit or a printed electronic circuit. In addition, the display system may be a screen, for example, a screen printed on paper, a Liquid Crystal Display (LCD), an Organic Light Emitting Diode (OLED), or an electrochromic display.

in other embodiments of the present invention, the conductive track of the analysis device may be made of carbon. This type of material of the conductive tracks may provide the analysis device with a relatively high biodegradability.

In other embodiments of the present invention, the analysis device further comprises a wireless communication module (bluetooth, NFC, RF, etc.) to transmit the results of the analysis performed by the analysis device to an external receiver.

Drawings

The foregoing and other advantages and features will be more fully understood from the following detailed description of embodiments, taken in conjunction with the accompanying drawings, which must be considered in an illustrative and non-limiting manner, in which:

Fig. 1a to 1 d: schematic illustration of a top view of a fuel cell according to different embodiments that can be used in an analysis device.

Fig. 2a to 2 c: schematic illustration of a top view of a lateral flow strip according to an embodiment in which two microfluidic channels are employed.

FIG. 3 a: a schematic illustration of the catholyte and anolyte fluids flowing through the microfluidic channels is shown in fig. 1 b.

FIG. 3 b: schematic illustration of a 3D configuration of microfluidic channels and coupled cathodic and anodic regions through which catholyte and anolyte fluids flow.

FIG. 3 c: a schematic illustration of the catholyte, anolyte and electrolyte fluids flowing through the microfluidic channel is shown in fig. 1 c.

FIG. 4 a: schematic illustration of a top view of an analysis device for a liquid sample according to an embodiment of the present invention. In this case, a single microfluidic analytical channel is used, thereby simplifying the above configuration.

FIG. 4 b: schematic illustration of a top view of an analysis device for a liquid sample according to an embodiment of the present invention. In this case, a single microfluidic channel is also used; however, the electronic circuit and the display system are integrated in a separate unit connectable to the analysis device.

FIG. 5 a: schematic illustration of a top view of an analysis device for a liquid sample according to an embodiment of the present invention. In this case, the detection zone of the analysis device is formed by a first part acting as a detector and a second part acting as a transducer.

FIG. 5 b: schematic illustration of a top view of an analysis device for a liquid sample according to an embodiment of the present invention. In this case, the detection zone is also formed by two distinct elements: a detector and a transducer; however, the transducer elements are included in a separate unit with the electronic circuitry and the display system.

Fig. 6a and 6 b: the proposed analysis device is in particular a schematic illustration of an example when used as an automatic blood glucose meter.

Fig. 7a and 7 b: the proposed analysis device is in particular a schematic illustration of an example when being an automatic lateral flow reader.

FIG. 8: schematic illustration of a top view of an analysis device for a liquid sample according to an embodiment of the present invention. In this case, a single microfluidic analysis channel is used, and in order to communicate the analysis results, a wireless communication module is included.

Detailed Description

Fig. 1a shows a schematic illustration of a top view of a fuel cell. This fuel cell includes: a microfluidic channel (10), an absorbent-receiving region (11) coupled to the microfluidic channel (10) at one end of the microfluidic channel (10), and an absorbent-collecting region (12) coupled to the microfluidic channel (10) at an opposite end of the channel. In order to facilitate capillary action through the microfluidic channel, it is preferred that the end coupled to the absorbent collecting region (12) and the end coupled to the absorbent receiving region (11) are located at different heights, it being irrelevant which end is higher in particular.

This particular configuration of the fuel cell allows at least one fluid (i.e. a fluid comprising a fuel reactant) suitable for generating an electric current to be deposited in the absorbent-receiving zone (11). In addition, the fluids are allowed to flow through the microfluidic channel (10) by capillary action until reaching the collecting absorbent region (12) where the fluids are absorbed, thereby allowing continuous flow through the microfluidic channel (10).

the fuel cell of fig. 1a further comprises: a cathode region comprising at least one cathode (13) and an anode region comprising at least one anode (14) coupled to the microfluidic channel (10), such that electrochemical energy may be generated due to the interaction of the cathode region (13) and the anode region (14) with at least one fluid comprising a fuel reactant when continuously flowing through the microfluidic channel (10) by capillary action. In this embodiment, the fluid deposited in the single absorbent receiving region may comprise both reducing and oxidizing species, such that interaction of the cathode region (13) with the reducing species and interaction of the anode region (14) with the oxidizing species may create an electrochemical voltage between the cathode region (13) and the anode region (14). In this particular embodiment, the cathode region (13) is placed on the side of the microfluidic channel (10) and the anode region (14) is placed on the other side of the microfluidic channel (10).

Still referring to fig. 1a, the absorbent-receiving area (11) may comprise at least one chemical substance which has been immobilized in a defined area of the absorbent-receiving area (11) in advance, such that the substance can be dissolved by the addition of an external liquid, preferably an aqueous liquid.

Fig. 1b shows a schematic illustration of a top view of another fuel cell. This configuration is very similar to that shown in fig. 1a, except that the absorbent-receiving zone (11) comprises two absorbent-receiving sub-zones, respectively (11a) and (11b), which are separate from each other and are located on the same physical support. A catholyte fluid may be deposited on the first, receiving absorbent sub-zone (11a) such that the reducing species interacts with the cathode region (13), and an anolyte fluid comprising an oxidizing species, which may interact with the anode region (14), may be deposited on the second, receiving absorbent sub-zone (11 b). Alternatively, the first receiving absorbent sub-zone (11a) may comprise an oxidizing species previously immobilized in the area of the first receiving absorbent sub-zone (11a), and the second receiving absorbent sub-zone (11b) may comprise a reducing species previously immobilized in the area of the second receiving absorbent sub-zone (11 b). The immobilized oxidizing and reducing species may then be dissolved, for example, by the addition of an external liquid (preferably an aqueous liquid).

In the embodiment shown in fig. 1b, the microfluidic channel (10) comprises two branches (18), such that the absorbent-receiving sub-region (11a) is coupled to the microfluidic channel (10) through one of these branches (18), while the second absorbent-receiving sub-region (11b) is coupled to the microfluidic channel (10) through a second one of said branches (18). The first branch and the cathode region (13) are arranged substantially on the same side of the microfluidic channel (10) such that the cathode region (13) can substantially fully interact with the catholyte fluid when the catholyte fluid is flowing through the microfluidic channel (10). Correspondingly, the second branch and the anode region (14) are arranged substantially on the same side of the microfluidic channel (10), such that the anode region (14) may substantially fully interact with the anolyte fluid when the anolyte fluid flows through the microfluidic channel (10). More details of the flow of the catholyte fluid and the anolyte fluid are described later.

The configuration described in the previous paragraph implies a relative positioning between the first receiving-absorbent sub-region (11a) and the cathode region (13) and between the second receiving-absorbent sub-region (11b) and the anode region (14), which allows a more efficient generation of electrochemical energy than the embodiment of fig. 1 a. In fact, with this configuration of the fuel cell, a "clean" interaction between the catholyte fluid comprising at least one reducing substance and the cathode region (13) and a "clean" interaction between the anolyte fluid comprising at least one oxidizing substance and the anode region (14) can be obtained, and therefore the efficiency of the fuel cell is higher.

In this regard, fig. 3a shows the configuration of the microfluidic channel (10), the cathode region (13) and the anode region (14), which is similar to the configuration included in the fuel cell shown in fig. 1 b. Fig. 3a also shows how catholyte fluid (31) and anolyte fluid (30) flow through the microfluidic channel (10). In particular, the catholyte fluid (31) comprising the reducing substance may flow, such that a substantially complete interaction between the catholyte fluid (31) and the cathode comprised in the cathode region (13) may be achieved. Correspondingly, the anolyte fluid (30) comprising the oxidizing species may flow such that substantially complete interaction between the anolyte fluid (30) and the anodes contained in the anode region (14) may be achieved.

In this particular embodiment, fig. 3a also shows how the catholyte fluid (31) and anolyte fluid (30) may begin to mix after some distance of travel, forming a region known as the diffusion region (32). In this particular embodiment, the cathode region (13) and the anode region (14) are positioned in the microfluidic channel (10) at a sufficiently short distance relative to the end where the absorbent receiving sub-regions (11a) and (11b) are joined to prevent the diffusion region (32) from making contact with either cathode comprised in the cathode region (13), either anode comprised in the anode region (14), or both. Thus, although the catholyte (31) and anolyte (30) fluids may eventually mix, in this embodiment an interaction between the entirely catholyte fluid (31) and the cathode region (13) and between the entirely anolyte fluid (30) and the anode region (14) is ensured.

Fig. 3b is a schematic illustration of a 3D microfluidic channel (10) and the configuration of the cathode region (13) and the anode region (14) according to another embodiment. This configuration is an alternative to the configuration shown in fig. 1b and 3 a. In this case, the first receiving absorbent sub-zone (11a) and the second receiving absorbent sub-zone (11b) (not shown in fig. 3 b) are arranged such that the flow of catholyte fluid (31) is substantially achieved above the flow of anolyte fluid (30). Thus, the cathode region (13) is arranged in an upper region of the microfluidic channel (10), while the anode region (14) is arranged in a lower region of the microfluidic channel (10). This configuration of fig. 3b allows to generate an electrochemical energy substantially equal to the configuration of fig. 1b and 3 a.

Fig. 1c shows a schematic illustration of a top view of another fuel cell. In this case, the difference from the fuel cell shown in fig. 1b is that: this embodiment further includes a third absorbent-receiving sub-zone (11c) separate from the first absorbent-receiving sub-zone (11a) and the second absorbent-receiving sub-zone (11 b). Electrolyte fluid may be deposited in the third absorbent sub-region (11c) and may be disposed in relation to the first receiving absorbent sub-region (11a) and the second receiving absorbent sub-region (11b) such that the electrolyte fluid at least partially keeps the catholyte fluid (31) and the anolyte fluid (30) separated as the catholyte fluid (31) and the anolyte fluid (30) flow through the microfluidic channel (10) by capillary action.

In the embodiment shown in fig. 1c, the mixture of catholyte fluid (31) and anolyte fluid (30) may be delayed relative to the mixture produced in the configurations of fig. 1b, 3a and 3 b. In this regard, fig. 3c shows how electrolyte fluid (33) flows between catholyte fluid (31) and anolyte fluid (30) to delay mixing of catholyte fluid (31) and anolyte fluid (30). Region (34) refers to a mixture of catholyte fluid (31) and electrolyte fluid (33). Region (35) refers to the mixture of anolyte fluid (30) and electrolyte fluid (33). It can be clearly seen that, at an "intermediate" flow of the electrolyte fluid (33), the diffusion zone (32) representing the mixture of catholyte fluid (31) and anolyte fluid (30) appears later than in the embodiment without such an "intermediate" flow of the fluid electrolyte (33).

In any of the embodiments described above, the microfluidic channel (10) and any of the absorbent regions (11) and (12) may be made of a paper-based material, e.g., filter paper, silk paper, cellulose paper, writing paper, etc. Alternatively, they may be made of other suitable materials, for example, nitrocellulose acetate, cellulose, fabrics, polymer layers, and the like. Since paper-based materials are considered to be low cost, the microfluidic channels (10) and the absorbent regions (11) and (12), respectively, are preferably made of this type of material. Furthermore, paper is a completely biodegradable material. Thus, the paper facilitates the availability of inexpensive and biodegradable fuel cells.

Furthermore, either one of the microfluidic channel (10) and the receiving or collecting area comprising paper as the main material may be obtained by two different methods or a combination thereof. The first method involves cutting the paper into the desired shape, whereby the resulting structure corresponds to a microfluidic channel. The cutting may be performed by mechanical action using, for example, scissors, a knife or an automated device (e.g., a guillotine), or using a laser, etc. A second method involves defining hydrophobic regions on the total surface of a porous material, preferably paper. The definition of the hydrophobic region may be accomplished by impregnating the porous matrix with photoresist, wax, teflon, hydrophobic chemicals, etc., or may be accomplished by applying a chemical treatment to alter the wettability.

Fig. 1D is a schematic illustration of a 3D paper sheet with microfluidic channels. The microfluidic channel is obtained by defining a hydrophobic region (16), wherein said hydrophobic region (16) in turn defines a hydrophobic region (paper) (17) constituting the desired microfluidic channel. The hydrophobic region (16) may be obtained, for example, by applying any of the techniques discussed above.

Preferably, the microfluidic channel (10) and the receiving and collecting absorbent regions (11) and (12), respectively, are obtained by applying a cut, since it is speculated that a cut is less costly than other types of methods, such as the techniques based on the definition of hydrophobic regions discussed above.

Figure 2a is a schematic illustration of a top view of a lateral flow test strip according to an embodiment. The test strip comprises a fuel cell as described above and illustrated in figure 1 a. In addition, the strip comprises an analysis microfluidic channel (20) connected to the absorbent-receiving region (11) at one end of the channel (20) and a absorbent-collecting region (12) located at the opposite end of the channel (20). Thus, in this embodiment, the absorbent receiving region of the analysis microfluidic channel (20) is the same as the absorbent receiving region of the fuel cell, and the absorbent collecting region of the analysis microfluidic channel is the same as the absorbent collecting region of the fuel cell. The features described in connection with fig. 1a also apply to this embodiment of the test strip of the invention, in respect of the absorbent receiving area (11) and the microfluidic channel (10). Thus, this particular configuration may also allow a continuous flow of fluid from the absorbent-receiving region (11) into the absorbent-collecting region (12), where the fluid is absorbed, allowing the flow to continue by capillary action when the analytical microfluidic channel (20) is saturated.

As an alternative to the above embodiments, the test strip may comprise a receiving absorbent region and a collecting absorbent region connected to opposite ends of the analysis microfluidic channel (20), which absorbent regions are separate from a receiving (11) and a collecting (12) absorbent region (forming part of a fuel cell comprised in the test strip) coupled to the microfluidic channel (10).

In the embodiment shown in fig. 2a, the test strip comprises a detection zone (21), the detection zone (21) having at least one electrochemical sensor coupled to the analytical microfluidic channel (20) such that the electrochemical sensor can interact with a sample to be tested, preferably a biological sample, when the sample flows through the analytical microfluidic channel (20) by capillary action. This interaction, in combination with a suitable electrical input signal, may produce a corresponding electrical output signal representative of the test results. The electrochemical sensor may be based on a carbon electrode, said material contributing to the biodegradability of the test strip.

The test strip can also comprise: an electronic circuit (23); a display system (24), preferably a screen; and a plurality of electrically conductive tracks (22), (25) and (26) connecting the electronic circuit (23) with the anode (14) and cathode (13) regions of the fuel cell, the detection region (21) and the display system (24). The electronic circuit (23) may be a silicon-based microelectronic circuit. Furthermore, the display system (24) may be a screen printed on paper, for example based on a suitable polymer. Furthermore, the conductive tracks (22), (25) and (26) may be made of carbon. These features can make the test strip highly biodegradable. As an alternative to carbon, the conductive tracks (22), (25) and (26) may be made of a conductive polymer, a metal (e.g. copper or gold metal) or any combination thereof.

Electrically conductive tracks (22) connecting the electronic circuit (23) with the anode region (14) and the cathode region (13) of the fuel cell allow the electronic circuit (23) to receive current from the fuel cell. The conductive tracks (25) connecting the electronic circuit (23) with the electrochemical sensors comprised in the detection zone (21) allow the electronic circuit (23) to provide a sufficient electrical input signal to the electrochemical sensors (21). Depending on the implementation logic, the electronic circuit (23) can derive these electrical input signals from the current generated by the fuel cell, which are necessary for the electrochemical sensor (21) to perform a suitable interaction with the sample to be analyzed. This interaction of the electrochemical sensor (21) with the sample, preferably a biological sample, and a suitable electrical input signal may produce an electrical output signal representative of the result of the analysis. The sensors in the detection zone (21) can send these electrical output signals to the electronic circuit (23) through corresponding conductive tracks (25). Depending on the implementation logic, the electronic circuit (23) can convert these electrical output signals into visible electrical signals and send them to the display system (24) via the corresponding conductive tracks (26).

The test strip may further comprise a pre-treatment region (not shown in fig. 2 a) which may be coupled to the microfluidic channel of the fuel cell (10) at a site between the receptive absorbent region (11) and the cathode region (13) or the anode region (14). In addition, such a pre-treatment region may also be incorporated into the analytical microfluidic channel (20) at a point between the absorbent-receiving region (11) and the detection region (21) of the sample. This pre-treatment region may have a configuration suitable for carrying out different types of pre-treatments, such as filtering, separating, screening liquids that may flow through the microfluidic channels and/or the analytical microfluidic channels (20) of the fuel cell (10). To design and/or establish such regions, known pretreatment principles may be utilized, such as those described in patent applications WO2009121041a2(a. siegel et al) and WO2011087813a2(p. yager et al).

Figure 2b is a schematic illustration of a top view of a lateral flow test strip according to other embodiments of the present invention. The test strip is very similar to the test strip shown in fig. 2a, except that the test strip of fig. 2b comprises a fuel cell of the type described with reference to fig. 1b, whereas the test strip of fig. 2a comprises a fuel cell of the type shown in fig. 1 a.

Figure 2c is a schematic illustration of a top view of a lateral flow test strip according to other embodiments of the present invention. The test strip is very similar to the test strip shown in fig. 2b, except that the test strip of fig. 2c comprises a fuel cell of the type described with reference to fig. 1c, whereas the test strip of fig. 2b comprises a fuel cell of the type shown in fig. 1 b.

an important aspect of the test strip shown in fig. 2a, 2b and 2c is that: the same fluid may be used as the fluid suitable for generating an electric current by the fuel cell and may be used as the sample for analysis in the detection zone (21). The fluid may be a biological sample, such as urine, blood, plasma, saliva, semen, sweat, etc. In this manner, the test strip can be a fully self-contained test strip, and thus, it can function without the need to connect to an external electrochemical sensor, display system, or electronic circuitry.

In some embodiments of the test strips described in this patent application, the detection zone (21) has the function of measuring or detecting a specific compound in the sample to be analyzed, preferably a biological sample. The detection may be based on different techniques, such as electrochemical techniques, optical techniques, etc. Other stages of pre-treatment of the sample and the area required to perform these steps in the strip may be included before the sample reaches the detection zone (21).

Electrochemical sensors can be manufactured by, for example, depositing one or more electrodes, which can be made of carbon in a porous matrix, which can be made of a paper-based material. One of the electrodes may be defined as a reference electrode, at least one of the electrodes as a counter electrode, and at least more than one of the electrodes as a working electrode. The deposition of the electrodes can be accomplished by various techniques, such as sputtering, evaporation, spraying, or printing techniques (e.g., inkjet, gravure, offset, flexographic, or screen printing). The electrodes may be functionalized to enhance detection capabilities. Functionalization of the electrodes can be formed by deposition of active materials, chemical treatment, and the like.

For the design and construction of the detection zone (21), suitable principles known to the person skilled in the art can be used, such as those disclosed in the following documents: pattern paper substrates and as alternative materials for low-cost microfluidic diagnostics, David R. Ballerini, Xu Li and Shen Wei. microfluidic and nanofluidics.2012, DOI:10.1007/s10404-012, 0999-2.

The electronic circuit (23) may correspond to an electronic circuit that may perform a plurality of tasks related to the test result to be generated. The circuit may comprise a combination of discrete electronic components and/or integrated circuits. For example, some embodiments may employ a fully custom Application Specific Integrated Circuit (ASIC) for performance improvement and area reduction.

The circuit may include modules such as power management, instrumentation, communications, data logging, etc. The power management module may take the energy generated by the fuel cell and increase the voltage to power the instrumentation module. The instrument module may supply power to sensors included in the detection area (21) for performing measurements, monitor signals of the sensors and compare these signals with reference values. The measurement results may be sent to a display system (24).

The electronic circuit (23) may further comprise a data logger to store information collected by the sensors in the detection zone (21). Furthermore, the electronic circuit (23) may further comprise a communication module to transmit the measurement result to, for example, an external receiver via radio frequency.

For designing and constructing the electronic circuit (23), preferably when it is a microelectronic circuit, suitable principles known to the person skilled in the art can be utilized, such as those disclosed in the following documents: alley Bran, Larry R.Faulkner, "Electrochemical Methods: Fundamentals and Applications", John Wiley & Sons,2001, ISBN 0-471-.

A display system (24) may allow the test strip of the present invention to display a visual indication of the measurement. This signal may be presented by using a screen, such as electrochromic technology, light emitting diodes, LCD, etc. Some of these display systems are described in the following documents: CG Granqvist, electrochromic devices, Journal of the European Ceramic Society, Volume 25, Issue 12,2005, pages 2907-; fundamentalsof Liquid Crystal Devices, author(s), Deng-Ke Yang, Shin-Tson Wu publishing Online:19OCT 2006, DOI: 10.1002/0470032030.

In particular embodiments, the display of the results may be due to a color change (e.g., prussian blue, etc.) produced by electrochemical complexes absorbed in a porous matrix comprised by the test strip.

The above construction can be simplified if two microfluidic channels, an analysis microfluidic channel (20) and a microfluidic channel (10), are merged into one, i.e. a microfluidic analysis channel (15). The microfluidic analytical channel (15) may comprise a material comprising hydrophilic polymers, textile fibres, glass fibres, cellulose and nitrocellulose; it is particularly preferred that such materials are biodegradable.

Fig. 4a shows a schematic illustration of such a simplified configuration. As can be seen from fig. 4a, the analysis device comprises a single microfluidic analysis channel (15), wherein a cathode region (13) comprising at least one cathode and an anode region (14) comprising at least one anode are coupled to said microfluidic analysis channel (15). Such a microfluidic analysis channel functions as an analysis channel (equivalent to the microfluidic channel (20) described earlier) with a detection zone (21) with a sensor. Conductive tracks (22), (25) and (26) connect the electronic circuit (23) with the anode region (14) and the cathode region (13), with the detection region (21) and with the display system (24). The electronic circuit (23) may be a silicon-based microelectronic circuit or a printed electronic circuit. Furthermore, the display system (24) may be a screen printed on paper (e.g. based on a suitable polymer), an OLED or an electrochromic display. Furthermore, the conductive tracks (22), (25) and (26) may be made of carbon. As an alternative to carbon, the conductive tracks (22), (25) and (26) may be made of a conductive polymer, a metal (e.g. copper or gold metal) or any combination thereof.

this particular embodiment has several advantages over the previous embodiments: it enables a reduction in the amount of sample required to generate electricity and perform the analysis; it simplifies the design of the analysis device and the amount of material required for its manufacture; and it also enables a simplification of the manufacturing process, thereby providing a higher cost-effectiveness to the analysis device.

In another embodiment, referring to fig. 4b, the proposed analysis device consists of two separate connectable parts; one part (28a) comprises a microfluidic analysis channel (15) with a detection zone (21) and a fuel cell on the microfluidic channel (15), the microfluidic channel comprising a receiving absorbent region (11), a collecting absorbent region (12), a cathode region (13) and an anode region (14), while the other part (28b) comprises an electronic circuit (23) and a display system (24). When an analysis is to be performed, the two separate parts (28a, 28b) are connected to each other by a connecting region (27). This particular embodiment presents the following advantages:

The electronic circuit (23) and the display part (24) can be reused several times, which is more environmentally friendly and more cost-effective than the single-use embodiment.

-by integrating the fuel cell with the detection zone (21) in separate parts, enabling the fuel cell to be adjusted to generate power for a single analysis. In this way, power is always available to perform the test. There is no need to plug the electronic components into any external power source or any additional battery.

The sensors included in the detection zone may include any of electrochemical, optical, piezoelectric, magnetic, surface plasmon resonance, sonic acoustic wave, or mass spectrometry sensors.

fig. 5a and 5b show further embodiments of the analysis device. In this case, the detection zone (21) is formed by two separate parts, the first part serving as a detector (21a) and the second part as a transducer (21 b). Both parts may be included in the analysis device, or alternatively, a first part serving as the detector (21a) may be included in the consumable part (28a) and a second part serving as the transducer (21b) may be included in the reusable part or in a separate unit (28 b). In the last case, the detection zone (21) is physically divided into two parts until the measurement is made, all connections being as shown in fig. 5 b.

In any of the above embodiments of fig. 4a, 4b, 5a and 5b, the absorbent regions (11) and (12) may comprise one or more sub-regions, as described in fig. 1b, 1c, 2b and 2 c. The absorbent receiving and collecting regions may be made of a material selected from the group consisting of paper-based materials, fiber-based materials and nitrocellulose-based materials.

Various exemplary embodiments are described below.

Fig. 6a and 6b show an example of the proposed analysis device working as an automatic blood glucose meter. The automatic blood glucose meter consists of two parts: an electronic reader (28b) and a disposable test strip (28a), as shown in fig. 6 a. The electronic reader comprises an electronic module (23) and a display system (24). In another aspect, a disposable test strip (28a) includes an electrochemical sensor and a power source. The test strip (28a) has a sample-receiving absorbent region (11), a microfluidic analytical channel (15) and a collecting absorbent region (12). The microfluidic analytical channel (15) includes a detection zone (21) for measuring the concentration of glucose in the sample using an electrochemical sensor. The microfluidic analytical channel (15) further comprises a power supply having a cathode region (13) and an anode region (14), the power supply being capable of generating electrical energy upon addition of a sample. The sensor and anode and cathode regions (13, 14) are connected to a connector region (27a) in the disposable test strip by conductive tracks (22, 25). For the measurement, the disposable test strip is inserted into the electronic reader (28b), as shown in fig. 6b, such that the connector area (27a) in the disposable test strip (28a) makes electrical contact with the connector (27b) in the connector area in the electronic reader (28 b). When a sample is added to the strip, the power supply provides power to the electronics module (23) to perform a measurement, which in turn reads a signal from a sensor in the detection zone (21) and displays the result in a display (24).

Fig. 7a and 7b show an example of the proposed analysis device working as an automatic lateral flow reader. The automatic lateral flow reader consists of two parts: an electronic reader (28b) and a disposable lateral flow test strip (28a), as shown in FIG. 7 a. The electronic reader (28b) comprises a reader detection zone (21b), an electronic module (23) and a display system (24). In another aspect, a disposable lateral flow test strip includes a test strip detection zone (21a) and a power source. The disposable test strip includes a lateral flow immunoassay tool made using known manufacturing techniques. The lateral flow immunoassay tool includes a sample receiving absorbent region (11) comprising the dry reagents required for the test, a microfluidic analytical channel (15) and a collecting absorbent region (12). The microfluidic analytical channel (15) includes a dipstick detection zone (21a) which is present in a reagent capture zone defining a test line and a control line. The microfluidic analytical channel (15) further comprises a power supply having a cathode region (13) and an anode region (14), the power supply being capable of generating electrical energy upon addition of a sample. The anode and cathode regions (13, 14) are connected to a connector region (27a) in a disposable test strip (28a) by a conductive track (22). To facilitate operation, the immunoassay tool, power supply, electrical track and connector are enclosed in a plastic housing. To make the measurement, the disposable test strip is inserted into the electronic reader, as shown in fig. 7b, such that the connector area (27a) in the disposable test strip (28a) makes electrical contact with the connector (27b) in the connector area in the electronic reader (28 b). When a sample is added to the strip, the power supply provides electrical power to the electronics module (23) to perform a measurement, which in turn uses the transducer in the reader detection zone (21b) to read the intensity of the line formed in the strip detection zone (21a) and display the result in a display system (24).

Referring to fig. 8, another embodiment of the proposed analysis device is shown. In this case, in order to transmit the result of the analysis performed by the analysis device to an external receiver, a wireless communication module 29 (bluetooth, NFC, infrared, etc.) is included.

The scope of the invention is defined in the following set of claims.

Claims

1. An analysis device for a liquid sample, comprising:

A microfluidic analytical channel made of wicking material having sufficient porosity to allow capillary flow of at least one liquid sample suitable for generating an electric current;

At least one absorbent receiving region coupled to the microfluidic analytical channel;

At least one collection absorbent region coupled to the microfluidic analysis channel;

A cathode region formed by at least one cathode coupled to the analysis channel;

An anode region formed by at least one anode coupled to the microfluidic analytical channel; and

At least one detection zone having at least one sensor connected to the microfluidic analytical channel,

Wherein each absorbent-receiving region and each absorbent-collecting region are connected to the microfluidic analytical channel such that when a liquid sample is placed in the absorbent-receiving region, the liquid sample flows through the microfluidic analytical channel by capillary action to the absorbent-collecting region and is absorbed at the absorbent-collecting region, and

Wherein the sensor interacts with the liquid sample to be tested as the sample flows through the microfluidic analytical channel by capillary action.

2. The device of claim 1, further comprising a first conductive track connecting the anode and cathode regions of the device with at least one electronic circuit connected via a second conductive track to at least one element selected from the group consisting of: comprising an electrochemical, optical, piezoelectric, magnetic, surface plasmon resonance, sonic or mass spectrometric sensor in said detection zone and said electronic circuit is further connected to at least one display system to visualize the results of the analysis.

3. An analysis device according to claim 2, wherein the electronic circuitry and display system are integrated in a separate unit connectable to the analysis device via the first and second conductive tracks.

4. The analysis device of claim 1, wherein the sensor coupled to a microfluidic analysis channel is an electrochemical, optical, piezoelectric, magnetic, surface plasmon resonance, sonic acoustic wave, or mass spectrometry sensor.

5. An analysis device as claimed in claim 4, wherein the sensor comprises two separate parts, a first part serving as a detector and a second part serving as a transducer.

6. An analysis device according to claim 2, wherein the electronic circuit and display system are integrated in a separate unit which is connectable via the first and second electrically conductive tracks to an analysis device comprising the sensor, wherein the sensor comprises two separate parts, a first part serving as a detector and a second part serving as a transducer, wherein the second part is integrated in the separate unit and the first part is integrated in the analysis device.

7. The analysis device of claim 1, wherein the microfluidic analysis channel is made of a material selected from the group consisting of: paper, hydrophilic polymers, textile fibers or glass fibers.

8. The device of claim 1, wherein each of the absorbent receiving and collecting regions is made of a paper-based material or a fiber-based material.

9. the assay device of claim 4, wherein the sensor is an electrochemical sensor comprising a carbon electrode.

10. The analysis device of claim 2, wherein the electronic circuit is a silicon-based microelectronic circuit or a printed electronic circuit.

11. The device of claim 2, wherein the display system for visualizing the results of the analysis comprises a screen printed on paper, an LCD, an OLED, or an electrochromic display.

12. The analysis device of claim 2, wherein the conductive tracks are made of carbon.

13. The analysis device of claim 1, further comprising a wireless communication module for communicating results of an analysis performed by the analysis device to an external receiver.

14. The analysis device of claim 1, wherein the material of the microfluidic analysis channel is cellulose.

15. The analysis device of claim 1, wherein the material of the microfluidic analysis channel is nitrocellulose.

16. The device of claim 1, wherein each of the absorbent receiving and collecting regions is made of a nitrocellulose material.