• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
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    • 专利摘要:
    Electrochemical device for sample analysis with insertable electrodes comprising a working electrode (we), a reference electrode (re), an auxiliary electrode (ae) and means of connection to a power supply and data recording system. The working electrode (we), the reference electrode (re) or the auxiliary electrode (ae) are staples (1) insertable that are arranged on a sample analysis surface (4). The working electrode (we) is also a modified insert (1) with a suspension of conductive carbon ink arranged on its surface. The invention is applicable in the detection, identification and quantification of chemical and biochemical substances, mainly in the sectors of clinical, environmental or agri-food analysis. (Machine-translation by Google Translate, not legally binding)
    公开号:ES2600454A1
    申请号:ES201600860
    申请日:2016-10-07
    公开日:2017-02-09
    发明作者:María Teresa FERNÁNDEZ ABEDUL；Paula Inés NANNI；Estefanía NUÑEZ BAJO；Lucia BLANCO COVIÁN；Andrea GONZÁLEZ LÓPEZ；María Del Carmen BLANCO LÓPEZ
    申请人:Universidad de Oviedo；
    IPC主号:
    专利说明:

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    Electrochemical device for sample analysis with insertable electrodes.
    The object of the present invention consists of a robust, simple, economical and high-precision electrochemical system composed of three stainless steel clips (reference electrode, working electrode and auxiliary electrode), in which the clip used as the working electrode It is coated with a carbon conductive ink. The clips are conductive elements of reduced size and size that can be used as electrodes for electrochemical detection in paper devices or other flat substrates, such as nitrocellulose membranes, textile materials, plastics, etc.
    In order to obtain the electrochemical measurement, the clips must be in contact with said flat substrates, so that the transfer of electrons between an electroactive species that is in solution and the surface of the clip can occur. This transfer is proportional to the concentration of the substance in solution and allows the quantification of several species of interest.
    The invention results from application in the detection, identification, and quantification of chemical and biochemical substances, mainly focused on the sectors of clinical, environmental or agri-food analysis.
    State of the art
    The development of effective tools for the sensitive detection of biomolecules and chemical compounds has gained special importance in the last decades in order to be applied for the analysis of samples, mainly in the medical, environmental and food sectors. The technological improvements of these devices are provided by miniaturization and simplification, two basic trends in Analytical Chemistry (M. Valcarcel, M. S. Cardenas. Automation and Miniaturization in Analytical Chemistry. Springer, 2000).
    Today this is very important for the decentralization of the analyzes, which are increasingly carried out outside the laboratory, especially in the medical field where "point-of-care" devices (PoC, care point) have appeared recently and they are undergoing a breakthrough (E. Schleicher. Diagnostic assays. Anal Bioanal Chem 2009, 393, 1391).
    Portability and the need to adapt to a profile of a user not specialized in the analysis prevail in the development of these devices (A. Warsinke. Point-of-care testing of proteins. Anal Bioanal Chem. 2009, 393, 1393). In this sense, paper analytical tests acquire an important role, since it is a low-cost substrate, added to other advantages such as allowing easy functionalization with biomolecules.
    The electrochemical detection fits perfectly with the idea of a decentralized analysis, since the techniques require a simple and low cost instrumentation (A. Nemiroski, DC Christodouleas, JW Hennek, AA Kumar, EJ Maxwell, MT Fernandez-Birch, GM Whitesides. A universal mobile electrochemical detector designed for use in resource-limited applications. Proc. Natl. Acad. Sci. USA, 2014, 111,
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    11984). The combination of electrodes in a paper substrate or other piano substrates makes it possible to manufacture PoC devices. (AC Giavan, DC Christodouleas, B. Mosadegh, HD Yu, BS Smith, J. Lessing, MT Fernandez-Birch, GM Whitesides. Folding analytical devices for electrochemical ELISA in hydrophobic RH paper. Anal. Chem., 2014, 86, 11999 ).
    For the manufacture of these electroanalytical devices, there are elements of different materials that can be used as electrodes. The mass-produced and commonly used stainless steel pins are conductive elements of reduced size and size, which can easily be used as electrodes for electrochemical detection in paper-based devices or other flat substrates and also in other microflulic material, such as wire , this being demonstrated in two scientific articles, for the determination of lactate (AC Glavan, A. Ainla, MM Hamedi, MT Fernandez-Birch, GM Whitesides. Electroanalytical devices with pins and thread. Lab Chip, 2016, 16, 112) and glucose (EC Rama, A. Costa-Garcla, MT Fernandez-Birch. Pin-based electrochemical sensor with multiplexing possibilities. Biosens. Bioelectron., 2016, in press). They have also been incorporated into a flow injection analysis system for glucose determination (E.C. Rama, A. Costa-Garcla, M.T. Fernandez-Birch. Pin-based flow injection electroanalysis. Anal. Chem., Accepted).
    However, the pinhead has an electronic area that is too small, which negatively impacts the test response and is not appropriate for interrogation of test lines (as is the case with the known lateral flow tests). It should also be considered that the pins are sharp and therefore are a material that has to receive a special safety consideration in a laboratory, in terms of handling and disposability.
    Finally, unlike optical methods such as fluorescence (LIF), electrochemical systems are easily miniaturizable and do not require complicated optical components, making the system much more portable.
    Description of the invention
    The present invention relates to an electrochemical system, preferably amperometric, that can be applied to a wide variety of laminar substrates such as paper, acetate transparencies or textiles, in order to detect, identify and quantify species, both metal ions as products of enzymatic reactions, of clinical, food and environmental interest, the cost being drastically reduced by using commercially available low-cost materials.
    It is therefore an aspect of the invention an electrochemical device for sample analysis with insertable electrodes comprising a working electrode (WE), a reference electrode (RE), an auxiliary electrode (AE) and means of connection to a system of power and data recording. The working electrode (WE), the reference electrode (RE) or the auxiliary electrode (AE) are characterized by insertable clips that are arranged on a sample analysis surface. In addition, the working electrode (WE) is a modified insertable clip with a suspension of conductive carbon ink arranged on its surface.
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    The transducer comprises three "U" stainless steel staples whose crowns act as an interface with the solution on the inside, one working (WE), one reference (RE) and another auxiliary (AE), of a cell electrochemical.
    Once connected by the tips by means of hook connectors to a potentiostatic equipment, a potential is applied between the working and reference electrodes and the electrochemical reactions take place at the electrode-dissolution interface (concave part of the clip).
    In a preferred embodiment the electrochemical detection system is amperometric.
    In another preferred embodiment, the inner part of the crown of the work clip (or work electrode) is pre-washed with acetone and impregnated three times with a carbon suspension in dimethyl ormamide (DMF), preferably 50% with curing. at a temperature of 80 ° C overnight.
    The material of the working electrode, as well as its area, are important for the proper functioning of the electrochemical detection system since they are directly related to sensitivity. Thus, as commercial staples are coated with an insulating material, those without washing have lower sensitivity and reproducibility than those that have been washed with acetone. In order to obtain a suitable electrodic material, the clips are modified with carbon, so that the electronic transfer is more suitable. However, if the carbon concentration in DMF is greater than or less than 60% and the number of impregnations is less than 3, these effects are not as obvious.
    In a more specific embodiment, the clips have a thickness of 500 ^ im, a width of 1 mm and crown and leg lengths of 10 and 5 mm, respectively.
    In a more preferable embodiment, a connection interface is used made of metallic interior female-type connectors coated with a plastic whose upper ends are attached to the legs of the staples and the lower ends are cables that facilitate connection to the potentiostat. These connectors, in turn, are reusable and maintain a fixed distance between the clips or electrodes of 1 mm facilitating the exchange of the clips.
    In a preferable configuration, the carbon working electrode is located between the reference and auxiliary electrodes (stainless steel clips) minimizing the working electrode-reference electrode distance (which decreases the ohmic broth) and the electrode is not reference interfered with by the current flowing between the working electrode and the auxiliary electrode.
    In a more specific embodiment, a PDMS block is manufactured using a mixture of silicone and crosslinking agent (as in conventional electrophoresis microchips) and subsequently cured at room temperature around the connector where the three clips are included, achieving once these are connected. , a relatively soft stable base for coupling and changing substrates where analytical tests (measurements, determinations ...) will be performed.
    Another aspect of the present invention is the application of the detection system that employs the electrochemical cell composed of the three clips for the quantification of
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    analytes that are either electroactive or are determined using bioassays with two types of brands: i) enzymes (eg wild horseradish peroxidase), ii) metal nanoparticles (eg silver). This has been demonstrated with two immunoassays that use the conjugate tags to specific antibodies: in the first case for the diagnosis of celiac disease (static detection) and in the second case for the diagnosis of pneumonia (flow detection, using flow strips side).
    In all cases, the use of the connection adapter is useful. In the first two cases (detection of an electroactive species), which can be the product of an enzymatic reaction since there is diffusion of an enzymatic product to the electrode surface, a high pressure between substrate and staple is not necessary, but in the case of metal nanoparticles, conjugated to an antibody that is immobilized on paper, require greater pressure between staples and paper. In any case, the measurement procedure is common, regardless of the molecule or ion to be determined, and is valid for any test that uses electroactive enzymes or molecules as an indicator species:
    a) Perform the biological recognition reaction, in both cases immunological sandwich type, whose analyte is an antigen or an antibody of interest.
    b) Wait for the reaction to complete and / or dry the sheet substrate.
    c) Attach the substrate to the staple-based electrochemical detector, connected to the potentiostat.
    d) Addition of the appropriate volume of measurement solution across the top of the clips so that all electrodes are wet for the proper functioning of the electrochemical cell.
    e) Recording of the cyclic or square wave voltamperogram to obtain the specific quantifiable analytical signal of the electroactive species, brand or product of the enzymatic reaction.
    Given the existence of commercial portable potentiostats, the ease of acquisition and low cost of stainless steel clips, the easy modification of the working electrode (which can be done in bulk without loss of signal due to its stability over time) and coupling to laminar substrates, which in turn are also low cost and disposable, rapid determinations can be carried out with fully disposable devices with a significant cost reduction and with easy use by people not specialized in any region, that is, applicable to field or field analysis or patient bedside test (PoCT).
    On the other hand, in the case of staples, the electrode area is larger than that provided by the head of a pin, so that a greater response is obtained, and is very appropriate for interrogation of test lines (such as the case of the known lateral flow test) since the clip acting as a working electrode can be placed directly on the line.
    The invention focuses on paper and its derivatives, such as nitrocellulose, as an electrode surface for subsequent experiments. The most commonly used paper for the construction of these devices is chromatographic paper, which is available in a
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    great variety of thicknesses and pore sizes, being able to be built only by cellulose, or in other cases by nitrocellulose. The great advantage that these types of papers have is that hydrophobic barriers can be printed on them, so that the work solutions are only in the area defined for this purpose and do not extend over the rest of the paper. In this way, the paper acts as a microfluldic platform formed by cellulose or nitrocellulose fibers that function as channels. (J.Yu, L.Ge, J.Huang, S.Wang, S.Ge. Microfluidic paper-based chemiluminescence biosensor for simultaneous determination of glucose and uric acid. Lab Chip. 2011, 11, 1286).
    Wax printing is very useful for making paper devices quickly and in large quantities (E. Carrilho, AW Martinez, GM Whitesides. Understanding wax printing: A simple micropatterning process for paper-based microfluidics. Anal. Chem. 2019, 81, 7091). To create the hydrophobic barriers a printer is used in which the ink is replaced by solid wax that melts at the same time of printing.
    The design of the electrochemical cell is one of the key steps when developing an electrochemical platform, the configuration selected for the integration and isolation of the electrochemical detection system being a three electrode potentiostatic system made with stainless steel clips preferably previously washed to remove the polymeric coating with which they are sometimes manufactured.
    To couple the paper devices to the electrochemical detection, the clip that acts as a working electrode with conductive carbon inks or pastes that allow the transfer of electrons with the electroactive substance must be modified. By connecting them to a potentiostat, a potential is applied between the working electrode and reference electrode and the current flowing between the working electrode and the auxiliary electrode is recorded.
    Carbon inks are the most used materials for the development of electrodes in paper devices and have been used in the first integration of an electrochemical detection in paper (W. Dungchai, O. Chailapakul, CS Henry, Electrochemical detection for paper -based microfluidics, Anal. Chem. 2009, 81, 5821) but other materials such as gold or silver inks are also used (WR de Araujo, TRLC Paixao, Fabrication of disposable electrochemical devices using silver ink and office paper, Analyst 2014, 139 , 2742; A. Maattanen, U. Vanamo, P. Ihalainen, P. Pulkkinen, H. Tenhu, J. Bobacka, J. Peltonen, A low-cost paper-based inkjet-printed platform for electrochemical analyzes, Sens. Actuat. 8, 2013, 177, 153).
    The fragility, flexibility and lightness of the paper do not favor a direct connection and, therefore, a polydimethylsiloxane (PDMS) connection interface, polymeric material used for the construction of devices with integrated electrochemical detection (AJ Blasco, l. Barrigas, MC Gonzalez, A. Escarpa, Electrophoresis 2005, 26, 4664; J. Wang, G. Chen, M. Pumera, Electroanalysis 2003, 15, 862; R.-H. Horng, P. Han, H.-Y Chen, K.-WK-W. Lin, T.-MT-M. Tsai, J. Micromech. Microeng. 2005, 15, 6; MJ Schoning, M. Jacobs, A. Muck, D.-T. Knobbe J. Wang, M. Chatrathi, S. Spillmann, Sens. Actuat. B, 2005, 108, 688; M. Castano-Alvarez, MT Fernandez-Birch, A. Costa-Garcla, Electrophoresis 2005, 26, 3160). On said interface, the clips are coupled through an outer plastic female connector with metal interior, and the paper substrate or any other flat substrate can slide under the clips of the detection system in a uniform and reproducible manner. The connection
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    between the device and the measuring instrument is in turn of great efficiency and low electrical resistance.
    Given the novelty of this electrodic platform, electrochemical detection has not been previously studied, or therefore used, in combination with paper devices so far.
    These devices (fully miniaturized, portable, disposable and low cost) are useful for the analysis, detection, identification and quantification of analytes of interest in the clinical, environmental and agri-food sector, among others. These can be electroactive species (particles and metal complexes, organic molecules ...) or proteins, DNA and other analytes of interest, which although they are not electroactive can be determined with bioassays.
    Description of the figures
    Fig 1. shows the scheme of a flat-tipped clip (1). Likewise, the way of coupling the clip to the connection interface (2) is shown, which consists of a plastic outer female connector with metallic interior (dotted line) from which cables come out from the bottom (3) that They are connected to the potentiostat. To maintain a reproducible distance and facilitate the placement of the three clips, the metal part of another female connector that was placed in parallel was subtracted and both connectors were surrounded by PDMS (not shown for simplifying the scheme) maintaining a distance between connectors of 10 mm (staple width). The set of connectors surrounded by PDMS define the connection interface (2).
    Fig 2A. It shows the procedure to follow for electrochemical detection with staples in a static mode on chromatographic paper. After placing the clips or electrodes (where the central clip has been impregnated with a conductive carbon suspension (1 x)) without pressing on the connection interface (2), a strip of chromatographic paper (4) with hydrophobic barriers slides of wax that delimit the test sites or areas (4 mm x 7 mm). Fig 2B shows the procedure to be followed for the detection of the solution (6) once the clips (1) have been placed in the connection interface (2). The solution to be measured (6) is pipetted through the top after placing one of the hydrophilic areas of the chromatographic paper (4) just below the staples (1), they must be pressed slightly towards the PDMS of the connection interface (2 ). Once the electrochemical signal is obtained, the clips (1) are changed and the strip of chromatographic paper is moved repeating the same procedure.
    Fig 3. shows the recorded clinical voltamperograms varying the potential from -0.42 to 0.8 V with a scanning speed of 100 mV.s-1 in a 1 mM ferrocene solution in 0.1 M phosphate regulatory solution of pH 7 obtained using different staples (1) and different hydrophilic area delimited in paper substrate for each measurement or voltamperogram.
    Fig. 4 shows the clinical voltamperograms of the enzyme substrate containing 3,3 ', 5,5'-tetramethylbenzidine (TMB), used in the CELIKEY commercial kit varying the potential from -0.2 to 0.5 V with a scanning speed of 100 mV .s-1. In Fig. 4A the measurements were made on the same staples (1) and different hydrophilic area delimited in the chromatographic paper substrate (4). In Fig. 4B the clinical voltamperograms for two different concentrations of the TMB substrate of the kit are shown;
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    the solid line shows the record in the initial dissolution of the substrate and the broken line the record in a 1: 5 dilution thereof.
    Fig. 5A shows the scheme of the result obtained in a lateral flow immunoassay with visual detection. The clips (1) used as electrodes are coupled as shown in Fig. 5B, placing the clip acting as a working electrode (1 x) on the test line (7) of the immunoassay. Since the mark is not enzymatic, it is placed in direct contact and pressed on the line. In Fig. 5C the addition of the supporting electro litho (11) is shown on the top of the clips (1), so that both the three clips (1) and the nitrocellulose membrane (6) are wetted with a Only drop. Once the electrochemical signal is obtained, both the clips (1) and the paper strip, consisting of the sample pad (9), the nitrocellulose membrane (6) and the absorbent pad (10), are discarded.
    Fig. 6A shows the clinical voltamerograms recorded with the staple-based detection system (1) corresponding to the Ag (0) / Ag (I) pair, varying the potential between -0.5 and 0.3 V with a scanning speed of 50 mV .s-1. The clinical voltamperograms correspond to two different concentrations of the analyte (in this case the prolinena pneumolysin). Fig. 6B shows the calibration curve performed with various concentrations of pneumolysin, specifically 1, 10, 25 and 50 ng / mL.
    Explanation of a preferred embodiment
    For a better understanding of the present invention, the following examples of preferred embodiment are described, described in detail, which should be understood without limiting the scope of the invention.
    Regardless of the example set out below, in both cases the connection interface (2) is used with the clips (1) previously placed according to the preferred arrangement in which the central clip is the working electrode (Fig 1).
    Example 1
    A detection system has been used, based on a carbon-stained stainless steel clip (1x) and two stainless steel clips (1y) inserted into the connection interface (2), coupled to strips of chromatographic paper (4) whose analytical areas were delimited with printed wax to avoid dispersion of the liquid. Thus, the liquids were confined in an appropriate region for staple detection. Said system was evaluated with a compound whose electrochemical behavior is well known (ferrocene) for a subsequent application in the determination of celiac disease in static.
    Once a stainless steel staple with carbon ink (1X) was modified to act as a working electrode (WE), the three staples that acted as electrodes were placed in the connection interface (2), leaving a gap between the part internal of the crown of the staples and the PDMS base so that the flat substrate can be easily introduced (Fig. 2A), in this case chromatographic paper (4). The connection interface (2) was connected to the potentiostatic system by means of hook connectors placed on the cables (3).
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    The creation of hydrophobic areas on the chromatographic paper substrate (4) was carried out by means of software design, surface printing with a wax printer and fusion at 110 ° C to spread the wax creating three-dimensional hydrophobic barriers that in this case were rectangles of 4 mm x 7 mm. To avoid the subsequent dispersion of liquids, possible loss of analytes and contamination of the PDMS support, a rigid and fine plastic base (called backing) was adhered. For each strip of paper that was used, 9 analytical cells were obtained, so that 9 measurements could be made in different solutions or drops.
    Once the hydrophobic barriers were created and the clips (1) were placed in the connection interface (2), the strip of chromatographic paper (4) was placed so that the hydraulic part coincided with the inner part of the crown of the clips. . These were pushed slightly down to the limit that allows the connection interface (2), so that the paper could slide from one area to another and the staples make contact through a fine dissolution film that acted as a supporting electrolyte or ionic conductor (Fig. 2B).
    Subsequently, 9 pL of 1 mM solution of ferrocene in phosphate regulatory solution pH 7 was added through the upper part of the staples and a potential cyclical scan between -0.2 and 0.8 V was applied with a scanning speed of 100 mV.s -one. Once the cyclic curve or voltamperogram was obtained, the clips were changed to new and clean ones and the strip of chromatographic paper (4) was moved so that a new hydraulic area coincided with the clips (1). The results (Fig. 3) show a great interelectrodic reproducibility and electrochemical behavior of the ferrocene / ferricinium ion pair similar to commercial electrodes. Alternatively, the same clips can be used and the paper slid to present a new analytical area to the three-clip electrode system.
    Once the correct and reproducible operation of the integrated system (chromatographic paper (4) in combination with the clips (1) connected to the potentiostat through the connection interface (2)) in a static format was confirmed, it was applied to the determination of anti-transglutaminase antibody, biomarker of celiac disease. For this, the immunoassays were carried out independently using a commercial ELISA kit, VARELISA (Celikey), which inclines ELISA plates with immobilized antigen (transglutaminase) and following the indications of the commercial house, detecting with the clips the product of the Enzymatic reaction of the HRP enzyme with a TMB / hydrogen peroxide mixture present in the well supernatant for different concentrations of anti-transglutaminase, positive control and negative control. In Fig. 4A the clinical voltamperograms recorded in a solution of the enzyme substrate for different paper / staple systems are shown and in Fig. 4B the voltamperograms corresponding to solutions of enzymatic substrate of two different concentrations are shown, where the clear difference can be seen Between both.
    Example 2
    In addition to the static format, the detection system based on the three stainless steel electrodes or clips mentioned in example 1 was also coupled to a lateral flow immunoassay or immunochromatographic test (5), consisting of a nitrocellulose membrane (6) in which bioreactive agents of interest were immobilized. Subsequently, the
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    sample and other reagents moved by capillarity to areas prepared as "test zone" (7) and "control zone" (8). The appearance of a colored line or two was attributed to a negative or positive test, respectively (Figure 5.a). The best known system is the pregnancy test, which is a clear example of the proximity to the commercialization of these devices and their rapid acceptance.
    The model used for the determination of pneumolysin has been selected as the model immunoassay for the development of the system, which is suitable for early detection of the pneumonia.
    The nitrocellulose strip was placed on a support card with adhesive (Fig. 5A). The test and control lines were drawn by dispensing the monoclonal anti-pneumolysin PLY-4 and mouse IgG monoclonal antibody respectively, at a rate of 0.100 pl / mm. The strips were then dried at 37 ° C for 30 minutes. The preparation of the test substrate was completed by placing a sample pad (9) and another absorbent pad (10) on both sides of the membrane, with an overlap of approximately 2 mm. The card was then cut into 5 mm strips. To perform the test, this strip (5) is immersed in standard solution or sample, in the presence of the detection antibody (PLY-7) conjugated to nanoparticles.
    The quantification was performed once the immunoassay has ended. For this purpose, the modified working electrode with a conductive carbon suspension (IX) was positioned on the test line, where the sandwich immunoassay (in this case) takes place, between the protein of interest or analyte and the capture antibodies (immobilized on the nitrocellulose membrane (6)) and detection (conjugated to a brand, usually of a visual type) (Fig. 5B).
    This system was evaluated with the detection of conjugated metal nanoparticles, specifically silver nanoparticles.
    These nanoparticles are attractive due to their excellent perspectives as a new biomarker for both qualitative (visual) and quantitative measurements, in addition to their good properties as a conductive material and their chemical stability, which makes them suitable for electrochemical detection. On the other hand, electrochemical behavior is well known, which facilitates electrochemical detection.
    For the detection, the same PDMS base system mentioned in example 1 (Fig. 2A) can be used with the difference that in this second example the clips (1) must be in direct contact and pressed against the nitrocellulose, for detection of metal nanoparticles. The connection with the potentiostat is then carried out following the same procedure as in example 1 by means of hook connectors (3) placed in the cables.
    In the present case, as a proof of concept and to ensure that there is good contact and pressure between the lateral flow immunoassay and the staples, a general stapler has been used, with the appropriate dimensions to be able to staple our staples directly. The connection to the potentiostat is achieved in the same way as in the case of the PDMS connection interface (2), with hook connectors (3), connected to the same clip (1) (Fig. 5C).
    With this last system, an acid solution (11), specifically 40 pL of 0.1 M nitric acid, was added to perform the electrochemical detection, to obtain the Ag (I) ions from the Ag (0) nanoparticles. This solution was added to the top of the clips (1), applying in turn a cyclic scanning of potentials between -0.5 5 and 0.3 V with a scanning speed of 50 mV.s-1. The measurement, unlike example 1, was performed instantaneously, since in this case the measurement surface was not delimited by hydrophobic barriers, so that the solution migrated through the base and surroundings of the nitrocellulose membrane producing a sample dilution.
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    Once the cyclic voltamperogram was registered, both the clips (1) and the lateral flow strip (5) were changed to a new one, with the same or different analyte concentration on the test line (7). Several cyclic voltamperograms are shown in Fig. 5B, in which, in addition to seeing the electrochemical behavior of the Ag (0) / Ag (I) pair, similar to that obtained with commercial electrodes, the signal is proportional to the analyte concentration present on the test line (7) of the lateral flow immunoassay (5).
    权利要求:
    Claims (15)
    [1]
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    1. Electrochemical device for sample analysis with insertable electrodes comprising a working electrode (WE), a reference electrode (RE), an auxiliary electrode (AE) and connection means to a characterized data feeding and recording system why:
    The working electrode (WE), the reference electrode (RE) or the auxiliary electrode (AE) are insertable clips (1) that are arranged on a sample analysis surface (4), where the working electrode (WE) it is a modified insertable clip (l) with a suspension of conductive carbon ink arranged on its surface.
    [2]
    2. Device according to claim 1 characterized in that the connection means is a connection interface (2) with holes where the clips (1) are inserted.
    [3]
    3. Device according to claim 2 characterized in that the connection interface (2) is a polymeric polydimethylsiloxane (PDMS) interface.
    [4]
    4. Device according to claim 1 characterized in that the analysis surface (4) is a chromatographic paper.
    [5]
    5. Device according to claim 4 characterized in that the chromatographic paper is slidable with respect to the staples (1) and comprises omniphobic barriers that delimit test areas.
    [6]
    6. Device according to claim 5 characterized in that the chromatographic paper comprises hydrophobic wax barriers that delimit test areas.
    [7]
    7. Device according to claim 1 characterized in that the analysis surface (4) is a textile sheet.
    [8]
    Device according to claim 1 characterized in that the analysis surface (4) is a lateral flow strip comprising a test line (7), on which the clips (1) are inserted so that the working electrode ( WE) is located on the test line (7) of lateral flow immunoassays and because the connection means comprise electrical conductors that can be attached to the clips (1).
    [9]
    9. Device according to claim 1 characterized in that all the clips (1) are modified with a suspension of conductive carbon ink arranged on their surfaces.
    [10]
    10. Device according to claim 1 characterized in that the working electrode (WE) is a modified staple (1) modified with a suspension of conductive carbon ink and metal or metal alloys arranged on its surface.
    [11]
    11. Device according to claim 1 characterized in that the reference electrode (RE) is a modified insert (1) with a metal suspension or metal alloys arranged on its surface.
    [12]
    12. Device according to claim 10 or 11 characterized in that the metal or metal alloys is silver or silver / silver chloride.
    [13]
    13. Device according to any of the preceding claims characterized in that the suspension comprises metallic or carbon nanomaterials.
    [14]
    14. Device according to claim 1 characterized in that it comprises several working electrodes (WE) in a multi-electrode format.
    [15]
    15. Device according to claim 1 characterized in that only two clips (1) are used, one acting as a working electrode (WE) and the other as a reference electrode (RE).
    10
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