CN108713139A - Test Component Analysis System - Google Patents

Abstract

A test element analysis system (110) for analytical examination of a sample (118), in particular a body fluid, is disclosed. The test element analysis system (118) includes an evaluation device (112) having a test element holder (114) for positioning a test element (116) containing a sample (118) and a measurement zone for measuring the test element (116) (134) for measuring the change in (122) that is characteristic of the analyte. The test element holder (114) comprises a contact element (132) having a contact surface (133) which allows the contact surface (117) of the test element (116) and the contact surface of the test element holder (114) ( 132) electrical contact between. The contact surface (133) of the contact element (132) of the test element holder (114) is provided with a conductive surface (145) comprising metal ruthenium (146).

Description

Test Component Analysis System

technical field

The invention relates to a test element analysis system for the analytical examination of samples and in particular human or animal body fluids and a method for producing the test element analysis system.

Background technique

Test element analysis systems are often used inter alia in medical diagnostics for analyzing bodily fluids such as blood or urine. The sample to be inspected is first applied to the test element. Here, the process steps required for the detection of an analyte are generally chemical, biochemical, biological or immunological detection reactions or physical interactions which lead to characteristic and measurable changes of the test element, especially in the region of the measurement zone of the test element. In order to determine this characteristic change, the test element is inserted into an evaluation device, which determines the characteristic change of the test element and provides this characteristic change in the form of a measured value for display or further processing.

The test element is usually designed as a test strip, which essentially consists of an elongated support layer, usually made of plastic material, and a measurement zone with a detection layer containing detection reagents and, if necessary, further auxiliary layers (such as filter layers). The test element of the invention additionally comprises contact surfaces (also denoted as contact areas) which can be used to create an electrical contact between the test element and the evaluation device. In the case of electrochemical analysis methods, conductor paths and electrodes are located on the test element. Even test elements that do not use methods of electrochemical analysis can have electrically conductive contact surfaces, for example in order to transfer calibration data or batch information stored on the test element to the evaluation instrument.

The attached evaluation device has a test element holder with special contact elements that make an electrically conductive contact between the test element and the evaluation electronics and measurement of the evaluation instrument. These contact elements are usually in the form of electrical plug connections to metal spring elements, which are often provided with a noble metal surface, usually made of gold or platinum. The test strip is inserted into the test element holder for the measurement, during which the contact surface of the contact element of the evaluation instrument is moved across the electrodes of the test element. In the end position the contact surface of the contact element of the evaluation device is then in contact with the contact surface of the test element. The electrically conductive connection between the test element and the evaluation device is produced by means of a pressing force which is defined in particular by the shape of the contact element and the spring force. This should in particular ensure that the transition resistance between the contact surface of the contact element of the evaluation instrument and the contact surface of the test element is as low as possible and as constant as possible for precise and reproducible signal transmission. In order to still obtain accurate measurement results (even after multiple test elements have been previously inserted) and therefore to obtain high and repeatable measurement accuracy especially with regard to such test element analysis systems are often used for many years or tens of thousands of A constant and repeatable transition resistance is especially important due to the fact that subsequent test strips are inserted twice). This is very important, especially in the clinical field, where such test systems often have to deal with high throughput.

A major advantage of pluggable contact devices is the ease of incorporating electrical connections and the ability to separate electrical connections so that test elements and evaluation equipment can be stored and used independently of each other. Because on the one hand the contact surfaces should ensure the best possible transfer of the current (this requires a certain contact pressure), but on the other hand the bonding of the contact connections and especially the repeated bonding and separation of the electrical connections can place great strain on the connections, The contact surfaces of the evaluation instruments are often provided with a noble metal layer, for example by plating or electroplating with gold, silver, platinum or palladium. The often high mechanical strains on the contact surfaces, especially due to wear, deposits or scratches on the contact surfaces, are therefore also a problem, since a certain contact pressure has to be ensured, for mechanical reasons a certain insertion path for a reliable electrical contact and the test element This is also necessary in particular to ensure guidance during insertion and mechanical stability in the plugged state. It is very important that the contact surfaces are as resistant as possible to external influences in order to produce a very safe and reliable contact between the contact surfaces of the electrical contact connection with the lowest possible contact resistance. In this connection, external influences can be of chemical, physical or mechanical type. Therefore, especially during the plugging process, the two contact surfaces rub against each other causing very high mechanical strains. Corrosion effects and especially crevice corrosion also have a negative effect on contact safety and contact resistance. Another problem with such test element analyzers is that the often used support material for the test element consists of an elastic and relatively soft plastic foil, on which the contact surfaces and electrodes are placed so that the structure can be placed on a relatively soft substrate. has disadvantages for precise contact.

A major disadvantage of such plug-in connected contact surface noble metal-noble metal pairs is that, even regardless of their geometry and/or pressing force, the metal surfaces are often damaged when bonding the contact surfaces and thus electrical contact problems arise. Such contact problems often manifest themselves in that the transition resistance between the contact element of the evaluation device and the contact surface of the test element becomes very high, or in extreme cases there may no longer be any electrical contact between the contact-connected parts . When viewed under a microscope, often results in a damaged image (especially in the case of flat contacts such as conductor paths or electrodes), characterized by significant changes in the thickness of the metal layer of these contact surfaces after insertion. Consequently, the second contact surface, in particular in the form of grooves, ridges and scratches, which moves across the metal layer of the electrode in certain regions, strongly deforms the metal layer of the electrode. This mode of damage occurs especially when the electrodes are mounted on relatively soft substrates. These deformations may become so great that in some areas the metal layer is completely stripped by the second contact surface moving across the metal layer. In this case, electrical contact between the test element and the evaluation device is no longer possible. Such a deformation of the metal layer serving as a contact surface manifests itself as an indeterminate and considerably increased transition resistance or a complete lack of electrical contact. Such contact elements are therefore not suitable for use in analytical systems intended to ensure reproducible determination of analytes over long-term use.

In US 8,673,213 B2, EP 1 725 881 B1, WO 2005/088319 A2 and the dissertation "Untersuchung und Optimierung von Kontaktsystemen inelektrochemischen Messgeräten" by S. Riebel in 2006, a contact surface having a hard material coated test element analysis system. This document discloses a test element analysis system for the analytical examination of samples, especially body fluids. The system comprises at least one test element with one or more measurement zones and contact areas (in particular electrodes or conductor paths) located on the test element. The sample to be examined is brought to the measurement zone and analyzed in order to determine the measured properties of the quantities used for the analysis. The system further comprises an evaluation instrument with a test element holder for positioning the test element in the measurement position and a measurement device for measuring the change in the characteristic. The test element carrier contains a contact element with a contact area which makes electrical contact between the contact area of the test element and the contact area of the test element carrier. One of these contact areas is provided with an electrically conductive hard material surface. Hard materials (due to their specific bonding properties) are understood to be materials that are very hard and in particular have a Vickers hardness greater than about 1000 kp/mm and include in particular carbides, borides, nitrides and silicides, high Melting point metals (such as chromium, zirconium, titanium, tantalum, tungsten or molybdenum, including mixed crystals and their complexes).

Despite the improvements due to the use of hard materials, there is still a need for even more robust and reliable contacts. A contact surface coated with a hard material may show wear of the material at the contact surface. In particular, contact surfaces coated with hard materials may exhibit deviations from the shape and surface quality of the contact surface during the service life. Contact with contact surfaces coated with hard materials can be highly sensitive to shape and surface quality. Therefore, quality problems may occur when using contact surfaces coated with hard materials. A contact surface coated with a hard material may exhibit transition resistance drift during service life (for example, after many plugging operations, especially after tens of thousands of plugging operations). Furthermore, contact surfaces coated with hard materials may exhibit a run-in behavior with respect to transition resistance, also denoted as run-in behavior. Furthermore, the manufacture of contact surfaces coated with hard materials can be complex, requiring several processes and thus can be expensive. Furthermore, the process reliability of the production of contact surfaces coated with hard materials may be insufficient. A reel-to-reel process may not be possible.

In Paul C. Hydes: Electrodeposited Ruthenium as an Electrical ContactMaterial: A Review of its Properties and Economic Advantages, Platinum MetalsRev., 1980, 24, (2), 50-55, with particular reference to the properties of deposits in electrical contact applications A review of the development of ruthenium electrolytes is given.

US 6,029,344 A1 discloses a composite interconnection element for microelectronic components and a method for manufacturing the same. By forming an elongated element (core) of soft material (such as gold, aluminum, copper, and their alloys) into a resilient shape (including cantilever, S-shape, U-shape) and utilizing a hard material (such as nickel and other alloys; copper, cobalt, iron and their alloys; gold and silver; elements of the platinum group; noble metals) overcoated shaped elongate members formed to exhibit desired mechanical properties (such as elasticity for making pressure contacts) The interconnection elements of electronic components in order to impart desired spring (elastic) properties to the resulting composite interconnection elements. A final overcoat of material with superior electrical qualities such as electrical conductivity and/or solderability can be applied to the composite interconnection element. The elongate element may be formed from a wire or from a sheet material such as metal foil. The resulting interconnect can be mounted to a wide variety of electronic components, including direct mounting to semiconductor die and wafers (in which case the overcoat material anchors the composite interconnect to the terminals on the electronic component (or similar)), can be mounted to a support substrate used as an interposer, and can be mounted to a substrate used as a probe card or probe card insert. In one embodiment, by attaching the core to the end of a flat elongate member formed from sheet material, and at least the core is overcoated (the flat elongate element provides an overcoated core capable of absorbing electronic components non-planarity (tolerance) of the "floating" support) to form hybrid composite interconnect elements.

In US 5,409,762 A electrical contact materials with higher hardness and higher melting point are disclosed. In particular, a cover layer having at least one selected from transition metal groups Iva, Va, and VIa as a main component is described. The proposed material is described as being superior to Ag-type, Au-type, platinum group-type, etc. electrical contact material faces in terms of wear resistance and environmental resistance.

US 2002/0157948 A2 discloses a method for determining the concentration of an analyte (such as glucose or lactate) in a biological fluid (such as blood or serum) using techniques such as coulometric, amperometric and potentiometric methods Small volume sensor and manufacturing method. The sensor includes a working electrode and a counter electrode. The working electrode may comprise an inert, non-conductive substrate such as polyester fiber, upon which a suitable conductive layer may be deposited. Suitable conductive layers include gold, carbon, platinum, ruthenium dioxide, palladium, and conductive epoxies.

US 6,134,461 A describes an electrochemical analyte sensor formed using conductive traces on a substrate. The sensor can be used to determine and/or monitor the level of an analyte in an analyte-containing fluid in vitro or in vivo. The electrochemical analyte sensor includes a substrate and a conductive material disposed on the substrate, the conductive material forming a working electrode. The conductive traces are typically formed using conductive materials such as carbon (eg graphite), conductive polymers, metals or alloys (eg gold or gold alloys), or metal compounds (eg ruthenium dioxide or titanium dioxide). Typically, each of the conductive traces includes a contact pad made of the same material as the conductive material of the conductive trace. In one embodiment of US 6,134,461 A, a sensor with contact pads and a control unit with conductive contacts are disclosed. The opposing contact pads or conductive contacts are made using carbon, conductive polymers, metals such as gold, platinum or palladium group metals, or metal compounds such as ruthenium dioxide.

Such contacts with ruthenium dioxide can be disadvantageous, since the application of ruthenium dioxide can be complicated and expensive. In particular, galvanic coating may not be possible, and therefore it may be expensive and uneconomical to manufacture ruthenium dioxide contacts.

US 5,351,396 A, in another technical field, describes electrical wiring terminals, electrical contacts of relays or switches for use in automobiles, industrial installations and the like. An electrical contact is provided on at least one of a pair of conductors, and the surface of the electrical contact is coated with a ceramic layer (which includes at least one selected from the group consisting of nitrides, carbides and borides of refractory metals. material), and a metal layer (which includes at least one material selected from the group consisting of Au, Pt, Pd, Ru, Ir and Os) is coated on the ceramic layer.

In EP 0 074 630 A2 a device comprising electrical contacts is disclosed. It is described that their electrical properties are mainly dependent on the contact surface of chemical compounds, where illustrative compounds are described as being chemically grouped as silicides, carbides, nitrides, phosphides, borides, sulfides and selenides. In EP 0 074 630 A2, compounds of platinum group metals as well as noble metals (ruthenium, rhodium, palladium, silver, osmium, iridium, platinum and gold) are excluded for economic reasons.

Despite the achievements of the literature described above, there is a need for a reliable and consistent relationship between the contact surface of the contact element of the evaluation device and the contact surface of the test element over a long period of time (especially under high mechanical strain) and even after multiple contact operations. Determine the need for electrical connections.

problem to be solved.

It is therefore an object of the present invention to provide a test element analysis system and a method for its manufacture which ensure the evaluation of the contact elements of a device over a long period of time (especially under high mechanical strain) and even after multiple contact operations A reliable and definite electrical connection between the contact surface of the test element and the contact surface of the test element.

Contents of the invention

This problem is solved by a test element analysis system for the analytical inspection of samples and a production method according to the features of the independent claims. Preferred embodiments which may be realized in isolation or in any arbitrary combination are listed in the dependent claims.

As used hereinafter, the terms "having", "comprising" or "comprising" or any grammatical variation thereof are used in a non-exclusive manner. Accordingly, these terms may refer to both situations in which there are no additional features in the entity described in this context other than those introduced by these terms, and situations in which one or more additional features are present. characteristic scenario. As an example, the expressions "A has B", "A includes B", and "A contains B" may refer to the following two situations: situations in which there are no elements in A other than B (i.e., situations in which A A scenario consisting solely and exclusively of B), and a scenario in which there are one or more additional elements in entity A in addition to B, such as element C, elements C and D, or even other elements.

Further, it should be noted that the terms "at least one", "one or more", or similar expressions when introducing a feature or element indicate that the corresponding feature or element may exist once or more than once and will generally be used only once. In the following, in most cases, when referring to corresponding features or elements, the expression "at least one" or "one or more" will not be repeated, and the irresistible fact is that the corresponding features or elements may exist once or more than one time. once.

Further, as used hereinafter, the terms "preferably", "more preferably", "especially", "more particularly", "specifically" are used in conjunction with optional features without restricting alternative possibilities ", "more specifically" or similar terms. Accordingly, features introduced by these terms are optional features and are not intended to limit the scope of the claims in any way. As the skilled person will recognize, the invention can be carried out by using alternative features. Similarly, it is intended without any restriction as to the alternative embodiments of the invention, without any restriction as to the scope of the invention, and without regard to making features introduced in this manner compatible with the invention. A feature introduced by "in one embodiment of the invention" or similar expressions makes an optional feature without any restriction on the possibility of combining other optional or non-optional features.

In a first aspect of the invention, a test element analysis system for the analytical examination of samples, in particular samples of bodily fluids, is disclosed. The test element analysis system includes an evaluation device having a test element holder for positioning a test element containing a sample and a measurement device for measuring changes in a measurement zone of the test element. This change is characteristic of the analyte. The test element holder comprises a contact element having a contact surface which allows electrical contact between the contact surface of the test element and the contact surface of the test element holder. The contact surface of the contact element of the test element holder is provided with an electrically conductive surface comprising metallic ruthenium.

As generally used in the present invention, the term "test element analysis system" may refer to any device configured for analytical examination of a sample. The test element analysis system may be configured for performing at least one analysis, in particular a medical analysis, of a test element which may contain a sample. The term "analyte" includes atoms, ions, molecules and macromolecules, especially biological macromolecules (such as nucleic acids, peptides and proteins, lipids, metabolites, cells and cell fragments). In the sense of the present application, a sample for an analyte examination is understood to mean an unchanged medium containing the analyte as well as an altered medium containing the analyte or a substance obtained therefrom. In particular, changes in the original medium can be carried out in order to dissolve samples, process analytes or carry out detection reactions. Typical samples are liquids, especially bodily fluids. Liquids can be pure liquids as well as homogeneous or heterogeneous mixtures such as dispersions, emulsions or suspensions. In particular, the liquid may contain atoms, ions, molecules and macromolecules, in particular biomacromolecules (such as nucleic acids, peptides and proteins, lipids, metabolites, or also biological cells or cell fragments). Typical fluids to be examined are bodily fluids such as blood, plasma, serum, urine, cerebrospinal fluid, tears, cell suspensions, cell supernatants, cell extracts, tissue lysates or the like. However, the liquid can also be a calibration solution, a reference solution, a reagent solution or a solution containing standardized analyte concentrations (so-called standards). As generally used in the present invention, the term "analyte examination or determination of an analyte" is understood to mean the qualitative as well as quantitative detection of an analyte. In particular, it is understood as the determination of the concentration or amount of the respective analyte, where the sole determination of the absence or presence of an analyte is also considered an analytical check.

Test element analysis systems are commonly used in analytical and medical laboratories. However, the invention is also directed to the field of application in which the analysis is carried out by the patient himself in order to continuously monitor his state of health (home monitoring). This is of particular medical importance eg for monitoring diabetic patients who have to determine the glucose concentration in their blood several times a day or patients who are taking anticoagulant drugs and therefore have to determine their coagulation status at regular intervals. For such purposes, the evaluation instrument should be as light and small as possible, and be battery operated and robust. Such a test element analysis system is described, for example, in DE 43 05 058 .

The test element is often in the form of a test strip which essentially consists of an elongated support layer (which usually consists of a plastic material) and a measurement zone with a detection layer containing detection reagents and possibly other auxiliary layers such as a filter layer band composition. Furthermore, the test element can contain other structural elements, such as dosing and conveying devices for the sample (such as channels or fleece), positioning devices to ensure precise positioning of the test element and thus precise measurements in the evaluation device (such as an aperture) or a coding element, for example in the form of a barcode or an electronic part (which is used to transfer specific parameters of the test element, such as calibration data or batch information, to the evaluation device).

The test element usually contains reagents in the measurement zone, the reaction of which reagents with the sample and in particular with analytes contained in the sample leads to a characteristic and measurable change of the test element which can be determined by the evaluation instrument which is part of the system. The measurement zone can optionally contain other auxiliary substances. The measurement zone can also only contain parts of reagents or auxiliary substances. In other cases, the detection reaction used to determine the analyte may not occur directly in the measurement zone, but the reagent mixture is transferred to the measurement zone for measurement after the detection reaction is complete. Those skilled in the art of analyte test elements or diagnostic test carriers are very familiar with suitable reagents and auxiliaries for carrying out analyte-specific detection reactions. In the case of analytically detected analytes, the measurement zone may eg comprise enzymes, enzyme substrates, indicators, buffer salts, inert fillers and the like. In addition to the detection reaction resulting in a color change, the person skilled in the art knows other detection principles that can be realized with said test elements, such as electrochemical sensors or chemical, biochemical, molecular biology, immunological, physical, Fluorescent or spectroscopic detection methods. The subject matter of the invention can be used in all these detection methods. This applies in particular to electrochemical analytical methods in which, as a result of an analyte-specific detection reaction, a change in the measurement zone, which can usually be measured electrochemically as a voltage or current, occurs.

In addition to such analytical systems using reagents, the subject-matter of the invention can also be used in reagent-free analytical systems in which, after the test element has been contacted with the sample, without additional reagents In this case, the characteristic properties of the sample are directly measured (eg its ion composition by means of an ion-selective electrode). The invention can also be used fundamentally in such analysis systems.

As used herein, the term "assessment device" generally refers to any device configured to perform analysis of a sample. The evaluation device includes a test element holder. The term "test element holder" generally refers to any device configured to house at least one test element and to position the test element so as to measure changes in the measurement zone of the test element. The evaluation device comprises a measurement device for measuring changes in a measurement zone of the test element. As used herein, the term "measurement device" refers to any device configured to measure and/or detect a change in at least one measurement zone of a test element. The evaluation device and/or measuring device can have at least one electronics unit with at least one electronics component. In particular, the electronics unit may comprise at least one device for performing the measurement of changes in the measurement zone of the test element, recording the measurement signal of the measuring device, storing the measurement signal or measurement data, transmitting the measurement signal or measurement data to another device an electronic component.

The evaluation device includes a test element holder for positioning the test element at a measurement position for carrying out the measurement. In order to determine the analyte, the test element can be placed in an evaluation device which determines the change in the property of the test element caused by the analyte and provides this in the form of a measured value for display or further processing. The analyte can be determined using a wide variety of detection methods known to those skilled in the art of instrumental analysis. In particular, optical and electrochemical detection methods can be used. Optical methods include, for example, the determination of characteristic changes in the measurement zone by measuring absorption, transmission, circular dichroism, optical rotational dispersion, refractometry or fluorescence. Electrochemical methods may in particular be based on the determination of characteristic changes in charge, potential or current in the measurement zone.

Within the scope of the present invention, a contact surface is understood to be an electrically conductive structure of a contact element or a direct contact of a test element in order to make electrical contact between the test element and the evaluation device. In the case of test elements, these are generally electrodes and conductor paths placed thereon, and in particular regions of these electrodes or conductor paths which have shaped (for example planar) structures for making electrical contact. The contact surface of the contact element can also be shaped eg as a flat element in order to generate the largest possible contact surface or area and thus a very safe contact and a low transition resistance. These contact elements can also have a curved shape, so that the insertion of the test element can be as simple and gentle as possible, for example in the case of spring or plug-in contacts. The contact surface of the contact element of the test element holder is provided with an electrically conductive surface comprising metallic ruthenium.

The term "contact element" may refer to any device configured to allow electrical contact between a contact surface of a test element and a contact surface of a test element holder. The contact elements that are part of the test element holder of the evaluation device can have a very wide variety of designs. They can be designed, for example, as sliding contacts, roller contacts, plug-in contacts, spring contacts, clip contacts or zero-force contacts. An inventive design of the contact surfaces can be particularly advantageous for contact reliability, especially for each contact surface in which the contact surfaces of the two elements involved in the contact connection move past each other while in direct contact until reaching their final position. Various types of contact elements (such as sliding contacts, plug-in contacts, spring contacts and clip contacts). Typical examples of contact elements are in particular sliding contacts, plug-in contacts, spring contacts and clip contacts. A wide variety of possible embodiments of such contact elements are described, for example, in US Patent No. 6,029,344.

The contact surface of the contact element of the test element holder is provided with a conductive surface comprising metallic ruthenium. The conductive surface may comprise pure metal ruthenium or a compound comprising metal ruthenium. Ruthenium can be applied by direct or indirect galvanic coating on conductive materials. Since pure material components often have unfavorable mechanical and chemical properties, such as brittleness, poor elastic properties, ruthenium surfaces can be formed, for example, by indirect galvanic coating on conductive materials. However, other deposition or coating techniques may additionally or alternatively be used. The test element holder may comprise at least one metal part comprising a contact element with a contact surface, wherein the metal part is made of at least one electrically conductive material different from ruthenium, wherein the contact element is fully or partially coated in the region with ruthenium conductive material. The conductive material may include copper. Ruthenium can be applied by direct or indirect galvanic coating on conductive materials.

Metal ruthenium and metal ruthenium compounds are distinguished from ruthenium dioxide. Ruthenium and oxide in ruthenium dioxide are inseparable compounds and have different chemical and conductive properties compared to metallic ruthenium. As far as contact surfaces containing ruthenium dioxide are concerned, since the production of ruthenium dioxide surfaces is complex and expensive, contact surfaces containing metallic ruthenium are advantageous. In particular, galvanic coating of ruthenium dioxide is not possible.

Surprisingly, the results show that the functionality of the contact element (i.e. run-in behavior and/or transition resistance) is essentially independent of the thickness of the ruthenium layer, especially at ruthenium layer thicknesses between 1 µm and 0.01 µm (preferably between 0.6 µm and 0.1µm) in the case of the range. The thickness of the ruthenium layer may be between 1 µm and 0.01 µm, preferably between 0.6 µm and 0.1 µm. For example, the thickness of the ruthenium layer may be 0.4 µm.

When applying a ruthenium layer to the electrically conductive material of the contact element, it may be advantageous first to apply one or more intermediate layers, in particular germ layers or protective layers, to the electrically conductive material and then to apply the ruthenium layer to these layers. The application of these interlayers can in particular lead to good adhesion and durable bonding between different materials. Thus, for example, an electroplating method can first be used to apply a layer to an electrically conductive material, which is coated by electroplating to produce a surface which is particularly suitable for the subsequent application of ruthenium. In addition, it is also possible to apply a protective layer that protects the underlying conductive material from chemical and/or physical damage such as corrosion when the ruthenium surface is damaged. Furthermore, the electrical properties of the contact elements, such as the transition resistance, can be influenced by a suitable choice of material for such an intermediate layer. Such an intermediate layer can be produced, for example, by applying particles made of suitable materials. Alternatively, in order to obtain a good and durable bond between the conductive material and the hard material layer, it is also possible to provide an additional intermediate layer, in which the surface of the conductive material of the contact element is prior to coating so that it has an improved coating. are handled in an overridden manner. The metal piece may comprise one or more contact portions electrically connected to at least one electronic component of the evaluation device, wherein the one or more contact portions remain free of ruthenium. The metal part can be a perforated bent part or a perforated deep-drawn part.

The test element analysis system may further include a test element having at least one measurement zone and a conductive contact surface. The test element can contain an electrically conductive contact surface and by means of this contact surface an electrical contact can be made between the test element and the evaluation device. In the case of electrochemical analysis methods, conductor paths and electrodes can be located on a test element which can be used to determine electrochemical changes in the sample and also apply an external voltage and/or current to the sample to be examined. In particular the electrochemical analysis on the test element can take place in the designed measuring zone between the electrodes, while measuring or applying electrical measuring signals emitted through them or actuating signals directed towards them via conductor paths. These conductor paths may contain designed flat areas forming contact surfaces that can be used to make electrical contact between the test element and the evaluation device. The conductor paths and contact surfaces can consist of noble metals. Test elements that do not use electrochemical analysis methods can also have conductive contact surfaces. For example, it may be advantageous to mount electronic components on the test element which are used to store specific parameters of the test element, such as calibration data or batch data, and transfer them to the evaluation instrument. For this purpose, these specific data are stored on test elements in electronic components or circuits. This data can be read and processed by reading the electronics of the evaluation device when the test element is introduced into the evaluation device.

The conductive contact surface may include one or both of electrodes or conductive paths. The conductive contact surface of the test element can be softer than ruthenium. In particular, it has proven to be particularly advantageous when the contact surface opposite the contact surface provided with the ruthenium surface consists of a material having a lower hardness than the ruthenium surface of the other contact surface. The conductive contact surface of the test element can be made completely or partly of metal. Metals are generally suitable for this and especially precious metals such as gold. Such materials have been widely used for contact surfaces, especially of electrodes and conductor paths on test components. According to the invention, it is therefore sufficient in many cases to provide the evaluation device with contact elements having a ruthenium surface, into which such conventional test elements can then be inserted. Surprisingly, it has been shown that the combination of a contact surface with a ruthenium material surface and a contact surface made of a material with a lower hardness than that of the ruthenium surface enables a high reproducibility of the transition resistance between the test element and the evaluation device sex.

As outlined above, in US 8,673,213 B2, EP 1 725 881 B1, WO 2005/088319 A2, it has been found (especially even after multiple insertions) that by coating the contact area with a conductive hard Contact areas made of noble metal improve a defined and reproducible electrical contact between the test element and the evaluation. However, after several plugging operations, in particular tens of thousands of plugging operations, the contact surfaces coated with hard material may be affected and/or damaged due to wear. Contact surfaces coated with hard materials may exhibit run-in behavior with respect to transition resistance and/or drift in transition resistance. The manufacture of a contact surface coated with a hard material can be complex, requiring several processes, and therefore can be expensive. Furthermore, the process reliability of the production of contact surfaces coated with hard materials may be insufficient. US 6,029,344 A1 , US 5,409,762 A and US 6,134,461 A disclose contact surfaces comprising contact materials of the platinum group which include ruthenium, rhodium, palladium, osmium, iridium and platinum. However, in EP 0 074 630 A2 compounds of the platinum group metals as well as noble metals (ruthenium, rhodium, palladium, silver, osmium, iridium, platinum and gold) have been excluded for economic reasons. Surprisingly, it has been found that a contact surface comprising the metal ruthenium ensures a low transition resistance between the contact surface of the test element holder and the test element, in particular less than about 50 ohms. Furthermore, a high reproducibility of the transition resistance between test element and evaluation device has been found with small dispersions. Further, surprisingly, no break-in behavior was found such that reliable measurement values were directly ensured. Furthermore, it has been found that the function of the contact element is substantially independent of the thickness of the ruthenium layer. In particular, it is possible to determine reliable measured values even in the case of very thin ruthenium layers. For example, reliable measured values can even be achieved at layer thicknesses of 0.01 µm. Thus, the durability (ie the number of subsequent mating operations) and functionality of the contact surfaces can be enhanced. Contact surfaces containing the metal ruthenium may be more advantageous, since the wear of relatively softer contact surfaces such as gold is further reduced and thus the adhesion of wear particles on the ruthenium contact layer of the device can be reduced. Furthermore, since the application of ruthenium can be performed by a galvanic coating process, the manufacture of ruthenium contacts may be shorter, less complex and therefore less expensive than hard material contacts or ruthenium dioxide contacts. Therefore, process time for manufacturing can be reduced and process reliability can be enhanced.

In a second aspect, a method for manufacturing a test element analysis system according to the invention is disclosed. For the definition and examples of the method, reference is made to the definitions and examples of the test element analysis described above. The method includes the following steps:

a) providing a contact element having a conductive surface comprising metal ruthenium; and

b) electrically connecting the contact element to at least one electronic component of the evaluation device.

Step a) may comprise providing at least one metal part comprising a contact element having a contact surface, wherein the metal part is made of at least one electrically conductive material different from ruthenium. Step a) may further comprise completely or partially coating the conductive material with ruthenium in the region of the contact element.

Summarizing the findings of the present invention, the following examples are preferred:

Embodiment 1: Test element analysis system for analytical examination of samples, in particular body fluids, comprising:

- an evaluation device with a test element holder for positioning a test element containing a sample and a measurement device for measuring a change in the measurement zone of the test element which is characteristic of the analyte, wherein the test element holder contains a a contact element of a surface that allows electrical contact between the contact surface of the test element and the contact surface of the test element holder,

- wherein the contact surface of the contact element of the test element holder is provided with a conductive surface comprising metallic ruthenium.

Embodiment 2: The test element analysis system according to the preceding embodiment, wherein the conductive surface comprises pure metal ruthenium or a compound including metal ruthenium.

Embodiment 3: The test element analysis system according to any one of the preceding embodiments, wherein the test element holder comprises at least one metal piece comprising a contact element having a contact surface, wherein the metal piece is made of at least one conductive material other than ruthenium material, wherein the conductive material in the region of the contact element is completely or partially coated with ruthenium.

Embodiment 4: The test element analysis system according to the preceding embodiment, wherein the conductive material comprises copper.

Embodiment 5: The test element analysis system according to any one of the two preceding embodiments, wherein the ruthenium is applied directly or indirectly to the conductive material by electroplating coating.

Embodiment 6: The test element analysis system according to any one of the three preceding embodiments, wherein the metal piece comprises one or more contact portions electrically connected to at least one electronic component of the evaluation device, wherein the one or more contact portions Parts remain ruthenium-free.

Embodiment 7: The test element analysis system according to any one of the four preceding embodiments, wherein the metal part is a perforated bent part or a perforated deep drawn part.

Embodiment 8: The test element analysis system according to any one of the preceding embodiments, further comprising:

- a test element having at least one measurement zone and a conductive contact surface.

Embodiment 9: The test element analysis system according to the preceding embodiments, wherein the conductive contact surface comprises one or both of electrodes or conductive paths.

Embodiment 10: The test element analysis system according to any one of the two preceding embodiments, wherein the conductive contact surface of the test element is softer than ruthenium.

Embodiment 11: The test element analysis system according to any one of the three preceding embodiments, wherein the conductive contact surface of the test element is made entirely or partially of gold.

Embodiment 12: A method for manufacturing a test element analysis system according to any one of the preceding embodiments, the method comprising the steps of:

a) providing a contact element having a conductive surface comprising metal ruthenium; and

b) electrically connecting the contact element to at least one electronic component of the evaluation device.

Embodiment 13: The method according to the preceding claim, wherein step a) comprises providing at least one metal piece comprising a contact element having a contact surface, wherein the metal piece is made of at least one electrically conductive material other than ruthenium, wherein step a ) further comprises completely or partially coating the conductive material with ruthenium in the region of the contact element.

Description of drawings

Further optional features and embodiments of the invention will be disclosed in more detail in the subsequent description of the preferred embodiments, preferably in conjunction with the dependent claims. Wherein, as the skilled person will realize, respective optional features may be implemented in isolation and in any feasible combination. The scope of the invention is not limited by the preferred embodiments. Embodiments are schematically depicted in the figures. In these figures, the same reference numerals refer to the same or functionally comparable elements.

In the picture:

Figure 1 shows a partial sectional view of a test element analysis system according to an embodiment of the present invention;

Figure 2 shows an exemplary view of a test element;

Figure 3 shows a detailed view of a contact element according to an embodiment of the invention;

Figure 4 shows a detailed view of a cross-section of a contact element with a conductive surface comprising metal ruthenium;

Fig. 5 shows the comparison of the experimental results of the durability test of the contact elements; and

Figure 6 shows the transition resistance as a function of plugging operation.

Detailed ways

FIG. 1 shows a test element analysis system 110 including an evaluation device 112 . The evaluation device 112 has a test element holder 114 for positioning a test element 116 containing a sample 118 . The test element holder 114 may be configured to position the test element 116 in the measurement position shown in FIG. 1 . The test element 116 can be fixed in the measuring position by suitable means, for example by a spring element 120 . To carry out the measurement, a sample liquid can be brought into the measurement zone 122 of the test element 116 . In the illustrated embodiment, this is accomplished by applying a liquid droplet to a sample application zone 124 provided at the end of the test element 116 and transporting it from that location to the measurement zone via a transport zone 126 (eg capillary channel). 122 to happen. A reagent layer 128 may be located in the measurement zone 122, which reagent layer 128 may be dissolved by the sample liquid and react with its constituents. This reaction may result in a detectable change in the measurement zone 122 . In the case of an electrochemical test cell, the measured electrical quantity can be determined by means of the electrodes 130 provided in the measuring zone 122 shown in FIG. 2 . The test element holder 114 comprises a contact element 132 with a contact surface 133 allowing electrical contact between the contact surface 117 of the test element 116 and the contact surface 133 of the test element holder 114 . In the measuring position, electrical contact can be made between the contact element 132 of the test element holder 114 and the test element 116 ( FIG. 1 ).

The evaluation device 122 comprises a measurement device 134 for measuring changes in the measurement zone 122 of the test element 116 which are characteristic of the analyte. The contact element 132 can be connected to measurement and evaluation electronics 136 which can be highly integrated in order to achieve a very compact construction and high reliability. In the case shown, they consist essentially of a printed circuit board 138 and an integrated circuit 140 . As such, the analysis system is of conventional construction and requires no further explanation.

FIG. 2 shows a partial view of an exemplary test element 116 . Analyte-specific changes can be detected from a portion of the analyte determination within the measurement zone 122 . In the case of the electrochemical test cell shown, the measured quantity of electricity is measured by means of electrodes 130 provided in the measurement zone 122 . The test element 116 may include a conductive contact surface 142 . In particular, the contact surface 117 of the test element 116 may be provided with an electrically conductive contact surface 142 . Electrical signals may be passed onto the conductive contact surface 142 via the conductive path 144 . These electrically conductive contact surfaces 142 can come into direct contact with the contact surfaces 133 of the contact elements 132 when the test element 116 is inserted into the test element holder 114 and thus make electrical contact between the test element 116 and the evaluation device 112 (see FIG. 3 ) . The conductive contact surface 142 of the test element 116 can be softer than the ruthenium-coated contact surface of the evaluation device. The conductive contact surface 142 of the test element 116 can be made completely or partially of gold. The test element 116 shown here is only one exemplary and minimized embodiment of a test strip. Test elements with other arrangements of electrodes and conductor paths and with several electrodes (eg reference electrodes) and additional structures (such as sample application and transport zones or reaction areas) can also be used within the scope of the invention.

FIG. 3 shows a detailed view of the contact element 132 according to one embodiment of the invention. The test element 116 is introduced into the test element holder 114 by insertion. Electrical contact can be made between the contact surface 133 of the contact element 132 and the conductive contact surface 142 of the test element 116 . In this case, the contact element 132 is designed such that it has elastic properties and thus exerts a defined contact pressure on the test element 116 . This is illustrated by the specific exemplary embodiment in which the contact element 132 can ensure electrical contact and positioning and fixing of the test element 116 .

FIG. 4 shows a detailed view of a cross-section of the contact element 132 . The contact surface 133 of the contact element 132 of the test element holder 114 is provided with a conductive surface 145 comprising metal ruthenium 146 . The test element holder 114 may include at least one metal part 148 comprising a contact element 132 having a contact surface 133 . The metal part 148 may be made of at least one conductive material 150 other than ruthenium. The electrically conductive material 150 in the region of the contact element 132 is completely or partially coated with ruthenium. The conductive material 150 may include copper. A layer of metal ruthenium 146 may be applied to the conductive material 150 of the contact element 132 and in this case an intermediate layer 152 may be present between two layers which may in particular be designed as adhesive or protective layers. Ruthenium may be applied by direct or indirect electroplating coating on the conductive material 150 . The metal component 148 may comprise one or more contact portions electrically connected to at least one electronic component of the evaluation device 112 , wherein the one or more contact portions remain ruthenium-free. The metal part 148 can be a perforated bent part or a perforated deep-drawn part.

Figure 5 shows a comparison of the experimental results of the endurance tests of the contact elements. Regarding the experimental setup, reference can be made to Figure 5.2 on page 44 and Figure 5.4 on page 45 and the corresponding description for reference. The docking cycle may include the step that a test area of a continuous strip of gold foil may be deposited on the pressure plate by a stop device. The test element can be moved over the test area of the gold foil strip. The material of the gold foil may be identical to the material of the contact surface of the test element according to the invention. The manner of contacting can be compared with the manner in which the test element is inserted into the evaluation device. Subsequently, the contact element can be moved away from the test area of the gold foil strip. A test area of the gold foil strip can be moved from the pressure plate, for example by a drive unit, and a subsequent test area of the gold foil strip can be deposited on the pressure plate. Although the test area and the contact element are in contact, the transition resistance between the contact element and the test area of the gold foil can be determined.

In the endurance test shown in Figure 5, the transition resistance can be determined at the test area and at eight contact points of the contact element. FIG. 5 shows the Ω in Ω as a function of the plug-in period z for a contact element with a conductive surface containing metallic ruthenium (curve 154) and, for comparison, for a contact element with a surface containing hard material (curve 156). Transition resistance R. Curve 156 shows the break-in behavior and the increase in transition resistance with increasing number of plugging operations, whereas curve 154 does not show the break-in behavior and the overall flat shape. Furthermore, the scatter behavior of the determined transition resistance is shown for a contact element with a conductive surface containing metallic ruthenium (reference number 158) and for comparison with a contact element with a surface containing a hard material (reference number 160) as Dashed area between minimum and maximum measurements. Surprisingly, it has been found that contact surfaces containing metallic ruthenium ensure low transition resistances and high reproducibility of the transition resistances with small dispersions.

FIG. 6 shows the transition resistance as a function of the plugging operation p. In this endurance test, the same test element 116 may be sequentially inserted three times into the test element holder 114 , wherein the contact surface 133 of the contact element 132 of the test element holder 114 is provided with a conductive surface 145 containing metallic ruthenium. The transition resistance (curve 162) is determined each time. For comparison, the test element 116 can be inserted three times in succession into a test element holder with a contact element with a hard material surface, and the transition resistance is determined each time (curve 164 ). In the case of using contact elements with hard material surfaces, failures were observed in the third plugging operation. With the use of the conductive surface 145 containing the metal ruthenium, functionality is ensured even during the third plugging operation. Surprisingly, it has thus been found that by using a contact surface comprising the metal ruthenium, the wear of the relatively softer contact surface is reduced compared to using a contact surface comprising a hard material.

List of reference numbers .

110 test element analysis system

112 Evaluation Equipment

114 Test element holder

116 test elements

117 contact surface

118 samples

120 spring element

122 measurement zone

124 sample application zone

126 conveyor belt

128 reagent layer

130 electrodes

132 contact element

133 contact surface

134 Measuring equipment

136 Measuring and evaluating electronics

138 printed circuit board

140 integrated circuits

142 Conductive contact surface

144 conductive path

145 conductive surface

146 Ruthenium metal

148 metal parts

150 conductive material

152 middle layer

154 curves

156 curves

158 Scattered behavior

160 Scattered behavior

162 curves

164 curves

Claims (12)

1. being used for sample（118）, particularly body fluid analysis check test element analysis system（110）, including：

It includes sample to have for positioning（118）Testing element（116）Testing element holder（114）Assessment equipment （112）With for measuring testing element（116）Measurement zone band（122）In variation measuring apparatus（134）, which is point Analyse the characteristic of object, wherein the testing element holder（114）Including with contact surface（133）Contact element（132）, the contact Surface（133）Allow testing element（116）Contact surface（117）With testing element holder（114）Contact surface（133）It Between electrical contact,

The wherein testing element holder（114）Contact element（132）Contact surface（133）It is provided with containing metal Ru （146）Conductive surface（145）,

The wherein testing element holder（114）Including comprising with contact surface（133）Contact element（132）It is at least one Metalwork（148）, the wherein metalwork（148）By at least one conductive material different from ruthenium（150）It is made, wherein the contact Element（132）Region in conductive material（150）It has been coated either completely or partly ruthenium.

2. according to the test element analysis system of preceding claims（110）, the wherein conductive surface（145）Including simple metal ruthenium Or the compound including metal Ru.

3. test element analysis system according to any one of the preceding claims（110）, the wherein conductive material（150）Packet Include copper.

4. test element analysis system according to any one of the preceding claims（110）, wherein by the way that coating is electroplated by ruthenium Directly or indirectly apply in conductive material（150）On.

5. test element analysis system according to any one of the preceding claims（110）, the wherein metalwork（148）Including It is electrically connected to one or more contact portions of at least one electronic unit of assessment equipment, the wherein one or more contacts Part is kept without ruthenium.

6. test element analysis system according to any one of the preceding claims（110）, the wherein metalwork（148）It is to wear Pore pressure comer pieces or perforation deep-draw part.

7. test element analysis system according to any one of the preceding claims（110）, further comprise：

There is at least one measurement zone band（122）And conductive contact surface（142）Testing element（116）.

8. according to the test element analysis system of preceding claims（110）, the wherein conductive contact surface（142）Including electrode （130）Or conductive path（144）In one or two.

9. according to the test element analysis system of any one of two preceding claims（110）, the wherein testing element Conductive contact surface（142）It is softer than ruthenium.

10. according to the test element analysis system of any one of three preceding claims（110）, the wherein testing element （116）Conductive contact surface（142）It is made of gold completely or partially.

11. method of the one kind for manufacturing test element analysis system according to any one of the preceding claims (110), should Method includes the following steps：

a）There is provided has the conductive surface containing metal Ru（145）Contact element（132）；And

b）Make contact element（132）With assessment equipment（112）At least one electronic unit electrical connection.

12. according to the method for preceding claims, wherein step a）Including providing containing with contact surface（133）Contact element Part（132）At least one metalwork（148）, the wherein metalwork（148）By at least one conductive material different from ruthenium （150）It is made, wherein step a）Further comprise coating conductive material completely or partially using ruthenium in the region of contact element （150）.