Patent Publication Number: US-2009238722-A1

Title: Pressure-Reinforced Fluidic Chip

Description:
BACKGROUND 
     The present invention relates to a fluidic chip device. 
     In liquid chromatography, a fluidic analyte may be pumped through a column comprising a material which is capable of separating different components of the fluidic analyte. Such material, so-called beads which may comprise silica gel, may be filled into a column tube which may be connected to other elements (like a control unit, containers including sample and/or buffers). 
     U.S. Pat. No. 7,182,371 discloses a manifold for connecting external capillaries to the inlet and/or outlet ports of a microfluidic device for high pressure applications. The fluid connector is adapted for coupling at least one fluid conduit to a corresponding port of a substrate that includes a manifold comprising one or more channels extending therethrough wherein each channel is at least partially threaded, one or more threaded ferrules each defining a bore extending therethrough with each ferrule supporting a fluid conduit wherein each ferrule is threaded into a channel of the manifold. The substrate has one or more ports on its upper surface wherein the substrate is positioned below the manifold so that the one or more ports is aligned with the one or more channels of the manifold. A device is provided to apply an axial compressive force to the substrate to couple the one or more ports of the substrate to a corresponding proximal end of a fluid conduit. 
     U.S. Pat. No. 6,936,167 discloses systems and methods for performing multiple parallel chromatographic separations. Microfluidic cartridges containing multiple separation columns allow multiple separations to be performed in a limited space by a single instrument containing high-pressure pumps and analyte detectors. The use of pressure fit interfaces allows the microfluidic cartridges to easily be removed and replaced within the instrument, either manually or robotically. 
     WO 2005/084808 by the same applicant Agilent Technologies discloses a frame for a microfluidic chip which can be used together with a laboratory apparatus. The frame is adapted at least for one of the features of receiving the microfluidic chip, and protecting the microfluidic chip, positioning the microfluidic chip relatively to the frame. 
     US 2004/0156753 A1 by the same applicant Agilent Technologies discloses a PEEK-based microfluidic chip device comprising two separate substrates which are bonded together to form channels where gases or liquids may move to accomplish applications of the microfluidic chip device. Thus, an internal cavity may be formed as a channel of the microfluidic chip device. 
     WO 2007/021810 discloses an apparatus and a method for delivering one or more fluids to a microfluidic channel. A microfluidic channel is provided in communication with a first conduit for delivering fluids to the microfluidic channel. Further, the apparatus and method can include a first fluid freeze valve connected to the first conduit and operable to reduce the temperature of the first conduit for freezing fluid in the first conduit such that fluid is prevented from advancing through the first conduit. 
     Operation of a liquid chromatography system may involve the application of a high pressure such as 1000 bar or more. This may be a challenge for the involved components of the liquid chromatography system. 
     SUMMARY 
     It is an object of the invention to provide an efficient fluidic chip device. The object is solved by the independent claims. Further embodiments are shown by the dependent claims. 
     According to an exemplary embodiment of the present invention, a fluidic chip device (such as a biochip for a chromatographic fluid separation system) adapted for processing a fluidic sample (such as a liquid and/or gaseous sample optionally comprising solid particles) is provided, the fluidic chip device comprising a substrate (such as a single-layer substrate or multi-layer substrate) comprising a fluidic conduit (such as a capillary or channel) for conducting the fluidic sample under pressure (for instance provided by a pump), and two reinforcing structures (such as physical bodies acting to strengthen the substrate by applying an external counter pressure) between which the substrate is arranged (for instance sandwiched), wherein the two reinforcing structures are connected to one another (for example by a connection structure such as one or more posts guided for example through the substrate or around the substrate) to reinforce pressure resistance of the substrate. 
     According to another exemplary embodiment, a method of fabricating a fluidic chip device for processing a fluidic sample is provided, the method comprising forming (for instance by etching or deposition) a fluidic conduit in a substrate through which fluidic conduit the fluidic sample is to be conducted under pressure, arranging the substrate between two reinforcing structures, and connecting the two reinforcing structures to one another to reinforce pressure resistance of the substrate. 
     According to an exemplary embodiment, a pressure stable fluidic chip device may be provided in which two or more reinforcing structures enclose at least a part of an outer surface of a substrate housing a sample channel, so that the substrate may be rendered more stable or resistant against high pressures which may occur when a fluidic sample is pumped through the fluidic conduit under pressure or when a fluid separation material is inserted into the fluidic conduit before using the device, i.e. during manufacture, under pressure. By interconnecting the reinforcing structures through or around the substrate by an interconnecting structure, an external mechanical support may be provide to stabilize the substrate even in the presence of a pressure of 1000 bar or more. 
     Next, further exemplary embodiments of the fluidic chip device will be explained. However, these embodiments also apply to the method. 
     The two reinforcing structures may be plates (such as a sheet of metal or glass or plastic, or any flat body structure or part having a planar surface). Thus, the two reinforcing structures may be essentially two-dimensional planar components which may be simply put on a surface of a planar substrate to thereby provide the substrate with an external support. 
     A shape and a surface area of the two reinforcing structures may be provided to match to a shape and to a surface area of the substrate. Thus, the design, geometry and dimension of a surface of the reinforcing structures may fit to a corresponding surface of the substrate, thereby ensuring a safe reinforcement over essentially the entire surface area of the substrate. 
     The two reinforcing structures may have a thickness which is larger than a thickness of the substrate. For instance, a thickness of the reinforcing structures may be at least twice, particularly at least five times of a thickness of the essentially two-dimensional substrate. Thus, relatively thick external stabilizing plates may be foreseen to apply an external pressure on the substrate (by an interconnection structure interconnecting the reinforcing structures) making the substrate more stable against high internal pressure. 
     Additionally or alternatively, a mechanical resistance of the two or more reinforcing structures may be larger than a mechanical resistance of the substrate. The term mechanical resistance may refer to the capability of a material to withstand external forces before being damaged, for instance before breaking. Providing reinforcing structures having a high mechanical resistance to surround at least a part of the substrate involve no limitations regarding the material selections of the substrate, so that the substrate constitution may be optimized independently to meet requirements related to the fluid separation procedure, for instance a biocompatibility requirement. 
     Particularly, the two reinforcing structures may be connected to one another to reinforce the substrate by a non-positive locking mechanism. Such a non-positive locking mechanism may be a friction-locked connection, i.e. a connection which is based on a frictional force. Such a non-positive connection may be a connection where there are no projections or recesses engaging in one another. In contrast to this, two components being connected in a non-positive manner may be held together by friction. Such a connection may require that the two components are pressed firmly together, for instance by a magnetic force. 
     Alternatively or additionally, the two reinforcing structures may be connected to one another to reinforce the substrate by a material connection such as a substance-to-substance bond where a connection is mediated by additional material such as a layer of glue. An example is that the reinforcing structures are connected by adhering. 
     Alternatively or additionally, the two reinforcing structures may be connected to one another to reinforce the substrate by a positive locking mechanism. Such a positive locking mechanism may be one in which two components lock together due to the way they are shaped, for instance a projection in one engages with a recess in the other, thereby preventing relative motion of the components. However, according to an exemplary embodiment, part of the reinforcing structures (or an additional connection element) may pass through the substrate, for instance penetrating through holes formed therein in order to be connected within the substrate. This may ensure a proper fastening and protection against high pressures. Alternatively, the connection between the two reinforcing structures may be guided around the substrate, for instance completely enclosing the substrate or having a post-like connection of the reinforcing structures guided around the substrate. This may allow to implement standard substrates which do not have to be adapted to reinforcing structures according to exemplary embodiments which may have an accommodation to accommodate such a substrate. 
     Particularly, the two reinforcing structures may be connected to one another to reinforce the substrate by traction anchoring. In other words, traction forces may be generated by such connected reinforcing structures tightly compressing the substrate to form a counterforce to the expanding effect of a high pressure in a channel of the substrate. 
     Any fastener may be used for connecting the two reinforcing structures which may be integrally formed with one or both of the reinforcing structures, or which may be provided as a separate component. Such fasteners may be used permanently or temporarily, when the latter configuration allows them to be fastened and unfastened repeatedly. Exemplary systems of joining or reinforcing the substrate are crimping, welding, soldering, bracing, taping, gluing, cementing, the use of adhesives, the use of forces involving magnets, vacuum, or pure friction. Also the implementation of screws, nails, bolts, hinges or springs may be possible. 
     Particularly, the two reinforcing structures may be arranged to encompass the substrate. Thus, the substrate may be partially or entirely surrounded or covered by the two reinforcing structures allowing to prevent uncontrolled impact of damaging expansive forces driving the substrate to expand in response to a pressure impinged on the internal fluidic channel. 
     The two reinforcing structures may be connected to one another to reinforce the substrate by a screwing connection. In such an embodiment, one or more threaded bores may be provided in the reinforcing structures and/or in the substrate to connect the reinforcing structures with the substrate sandwiched in between by fastening the screws, for instance using a corresponding screw nut. 
     It is also possible that the two reinforcing structures are connected using a clamping connection. This may involve sufficiently strong spring forces acting on the reinforcing structures or directly on the substrate to generate a counterforce in the opposite direction of expanding forces generated by a high pressure applied to the fluidic channel. 
     At least one of the two reinforcing structures may comprise a fluidic sample drain opening adapted to drain a fluidic sample discharging from the fluidic conduit. In a substrate such as a chip for biochemical analysis or the like, it is possible that the fluidic sample is to be drained after being guided through the fluidic channel out of a surface of the substrate which is, according to an exemplary embodiment, covered by one or both of the two reinforcing structures. In such an embodiment, a fluid adapter or a fluid interface may be formed in the reinforcing structure which may allow to get external access to the fluidic sample discharging from the fluidic conduit even when the corresponding surface of the substrate is covered by one of the reinforcing structures. 
     At least one of the at least two reinforcing structures may comprise an attachment piece adapted for inserting a separation substance in the fluidic conduit under pressure. A separation substance such as beads having fluid separation properties may also be filled in a channel under a high pressure, for example during manufacture. When the reinforcing structures surround the substrate at least during such a manufacturing or filling procedure, it can be ensured that the packing material is provided safely within a dedicated portion of the fluidic channel with a sufficiently large packing density. After such a fill-in procedure, it is possible to remove the two reinforcing structures for normal use. However, since also the pumping of a liquid sample through the fluidic channel may be performed under high pressure conditions during actual use of the fluidic chip device, it is also possible that the reinforcing structures remain enclosing the substrate during the actual separation procedure. 
     At least one of the two reinforcing structures may have a thickness (in a stacking direction of the substrate and the two reinforcing structures which may be located on top of one another) in a range between basically 1 mm and basically 30 mm, particularly in a range between basically 2 mm and basically 10 mm, more particularly in a range between basically 4 mm and basically 6 mm. Additionally or alternatively, the substrate may have a thickness (in a stacking direction of the substrate and the two reinforcing structures which may be located on top of one another) in a range between basically 25 μm and basically 300 μm, particularly in a range between basically 50 μm and basically 200 μm, more particularly in a range between basically 70 μm and basically 150 μm. The substrate may be a planar and very thin structure which may be essentially two-dimensional, for instance similarly shaped as a credit card. In contrast to this, the reinforcing structures may be for instance rectangular plates having a significantly larger thickness and stability, to thereby provide the required stabilizing forces. 
     The two reinforcing structures may comprise a metal. For instance a steel sheet may be appropriate, since it is sufficiently robust and mechanically stable and cheap as well. However, the reinforcing structures may also comprise a hard plastic, i.e. a plastic material having a sufficient mechanical stability. The stability should be such that the hard plastic reinforcing structures may be capable to bear pressure forces of 600 bar, particularly of 1200 bar. 
     The reinforcing structures may be formed by injection molding. They may be formed as injection molded parts manufactured separately from the substrate, or may be injection molded onto the substrate. The latter procedure has the advantage that this results in an automatic fastening of the reinforcing structures at the substrate during the injection molding procedure. 
     The substrate may be a multi-layer substrate. In other words, the substrate may be formed of a plurality of layers which may be connected to one another, for instance which may be laminated. Within any layer of such a multi-layer substrate, a structure for the fluidic chip application may be formed, such as a conduit, electrode structures, separation channels, frits, valves, heating elements, sensor elements such as temperature sensors, etc. By laminating such components together, a high performance fluidic chip device may be provided which however may suffer from the mechanical weakening of the laminated multi-layer structure. According to an exemplary embodiment, such a problem may be overcome by externally stabilizing such a multi-layer substrate, preventing delamination or the like. 
     The substrate may comprise one or more through holes through which a connection element (such as columns, posts or pillars) may be guided which connect(s) the two reinforcing structures to one another. By forming one or more of such through holes, a direct connection of the externally positioned reinforcing structures may be made possible, thereby providing additional mechanical support to the substrate relative to the reinforcement structures and between the two reinforcement structures. 
     The substrate may comprise a plurality of layers. For instance, three or five layers may form a laminar structure of the fluidic device which may allow for providing all the required components of the fluidic device within the layered structure. Particularly, the substrate may comprise a top layer, a bottom layer and at least one intermediate layer sandwiched between the top layer and the bottom layer. The at least one intermediate layer may comprise a conduit through which the fluidic sample is to be conducted. 
     The substrate may have an essentially rectangular cross section. Furthermore, the substrate may have a plate-like shape. Typical dimensions of the substrate are a thickness of 0.3 mm or less, and a dimension of several cm in length and in width. 
     At least a part of a processing element provided in the substrate may be filled with a fluid separating material. Such a fluid separating material which may also be denoted as a stationary phase may be any material which allows an adjustable degree of interaction with a sample so as to be capable of separating different components of such a sample. The fluid separating material may be a liquid chromatography column filling material or packing material comprising at least one of the group consisting of polystyrene, zeolite, polyvinylalcohol, polytetrafluorethylene, glass, polymeric powder, silicon dioxide, and silica gel. However, any packing material can be used which has material properties allowing an analyte passing through this material to be separated into different components, for instance due to different kinds of interactions or affinities between the packing material and fractions of the analyte. 
     At least a part of the processing element may be filled with a fluid separating material, wherein the fluid separating material may comprise beads having a size in the range of essentially 1 μm to essentially 50 μm. Thus, these beads may be small particles which may be filled inside the separation column. The beads may have pores having a size in the range of essentially 0.02 μm to essentially 0.03 μm. The fluidic sample may be passed through the pores, wherein an interaction may occur between the fluidic sample and the pores. By such effects, separation of the fluid may occur. 
     The fluidic chip device may be adapted as a fluid separation system for separating components of the mobile phase. When a mobile phase including a fluidic sample is pumped through the fluidic chip device, for instance with a high pressure, the interaction between a filling of the column and the fluidic sample may allow for separating different components of the sample, as performed in a liquid chromatography device or in a gel electrophoresis device. 
     However, the fluidic chip device may also be adapted as a fluid purification system for purifying the fluidic sample. By spatially separating different fractions of the fluidic sample, a multi-component sample may be purified, for instance a protein solution. When a protein solution has been prepared in a biochemical lab, it may still comprise a plurality of components. If, for instance, only a single protein of this multi-component liquid is of interest, the sample may be forced to pass the columns. Due to the different interaction of the different protein fractions with the filling of the column (for instance using a gel electrophoresis device or a liquid chromatography device), the different samples may be distinguished, and one sample or band of material may be selectively isolated as a purified sample. 
     The fluidic chip device may be adapted to analyze at least one physical, chemical and/or biological parameter of at least one component of the mobile phase. The term “physical parameter” may particularly denote a size or a temperature of the fluid. The term “chemical parameter” may particularly denote a concentration of a fraction of the analyte, an affinity parameter, or the like. The term “biological parameter” may particularly denote a concentration of a protein, a gene or the like in a biochemical solution, a biological activity of a component, etc. 
     The fluidic chip device may be or may be implemented in different technical environments, like a sensor device, a test device for testing a device under test or a substance, a device for chemical, biological and/or pharmaceutical analysis, a capillary electrophoresis device, a liquid chromatography device, a gas chromatography device, an electronic measurement device, or a mass spectroscopy device. Particularly, the fluidic chip device may be a High Performance Liquid device (HPLC) device by which different fractions of an analyte may be separated, examined and analyzed. 
     The processing element may be a chromatographic column for separating components of the fluidic sample. Therefore, exemplary embodiments may be particularly implemented in the context of a liquid chromatography apparatus. 
     The fluidic chip device may be adapted to conduct a liquid mobile phase through the processing element and optionally a further processing element. As an alternative to a liquid mobile phase, a gaseous mobile phase or a mobile phase including solid particles may be processed using the fluidic chip device. Also materials being mixtures of different phases (solid, liquid, gaseous) may be analyzed using exemplary embodiments. 
     The fluidic chip device may be adapted to conduct the mobile phase through the processing element(s) with a high pressure, particularly of at least 600 bar, more particularly of at least 1200 bar. In the context of such a high pressure application, the corset function of the interconnected reinforcing arrangement may be particularly of interest. 
     The fluidic chip device may be adapted as a microfluidic chip device. The term “microfluidic chip device” may particularly denote a fluidic chip device as described herein which allows to convey fluid through microchannels having a dimension in the order of magnitude of μm or less. 
     The fluidic chip device may be adapted as a nanofluidic chip device. The term “nanofluidic chip device” may particularly denote a fluidic chip device as described herein which allows to convey fluid through microchannels having a dimension in the order of magnitude of nm or less. 
     Exemplary embodiments relate to high performance liquid chromatography plastic chips which may have limitations regarding usable pressure. However, when using laminated structures, there may be a danger of leakage upon application of a high pressure. To meet the above shortcoming, exemplary embodiments provide a plastic chip within a metal corset to counteract the internal pressure by the externally applied corset. As alternatives to a metallic corset, other corset materials may be used, such as a sufficiently stable plastic part or an injection molded part. The chip and the corset may be connected by screwing, lamination, etc., to thereby provide an improved pressure resistance. 
     During packing separation material within the chip, it is possible to maintain the corset during the fill-in procedure, wherein the corset may be taken off afterwards again. 
     Particularly in a package material filled channel within such a substrate, pockets may be formed at a border between such a channel and the laminated structures. Such pockets as well as bumps on an external surface of the substrate which may be formed upon application of a high pressure may have a negative impact on the performance of the fluidic chip device and may become more severe with higher operation pressures and smaller devices. However, the provision of an interconnected corset structure may prevent undesired formation of pockets and/or bumps as well as may prevent or inhibit undesired delamination. This may allow to obtain a pressure stability of 1000 bar and more. The mechanical robustness can be improved by exterior lamination of a metal corset or the like onto a structure. 
     However, according to another exemplary embodiment, it is also possible to integrate at least a part of the reinforcing structures within a sandwich structure. For example, the reinforcing structures may be arranged to enclose a substrate but may be, in turn, externally surrounded by further layers or structures related to the fluidic chip device. 
     The chip may be encompassed by the reinforcing structures which may form channel-free cover layers, and may particularly provide the reinforcing function by an interconnection. It is possible that one or more additional elements or features are formed on and/or in the reinforcing structures, such as a recessed grip or the like. 
     When configuring the reinforcing structure, it is also possible to use a material or a dedicated feature promoting a heat exchange or thermal exchange with an environment. For that purpose, it may be advantageous to use steel, a steel sheet, aluminium, copper, titanium, or other metals as a material for the reinforcing structures, and/or to provide thermo-coupling elements in the reinforcing structure. 
     It is also possible to use a sufficiently rigid plastic such as PEEK (Polyetheretherketone). The use of ceramic materials such as silicon carbide, aluminium oxide, magnesium oxide, etc. for the reinforcing structures is possible as well. 
     The substrate may be adapted to be connectable with the corset in a reversible or detachable manner, for instance the corset may be applied only for filling separation material in the channel and/or for operating the device under high pressure. 
     By improving the pressure resistance of the system, the operation safety for a user may be also improved. Therefore, also an existing microfluidic component may be reinforced later, for example by retrofitting. 
     According to an exemplary embodiment, a microfluidic multi-layer chip (which may comprise laminated layers and may be formed of glass, plastic, metal (for instance having several thin metal sheets connected to one another) and/or ceramic material) having a corset of two enforcement layers may be provided. Such a multi-layer chip (which may be manufactured on the basis of PEEK) on the one hand and the reinforcing layers on the other hand may be manufactured from different materials. 
     Regarding reinforcing the chips by embodying it with plastic, particularly the following procedures may be implemented:
         1. Use transfer or compression molding, this will give the possibility to use thermoset materials   2. Use liquid transfer molding   3. Use injection molding for thermoplastic materials       

     Particularly, the following materials may be used in case 1: Materials that have acceptable mechanical properties, good chemical resistance and good dimension stability like some grades of Alkyds and phenolics materials. 
     Particularly, the following materials may be used in case 2: Materials like Polyimide (PI) or different epoxies can be introduced in a transfer mold in liquid state, filling the cavities; after that the materials cure under temperature conditions reinforcing the chips. 
     Particularly, the following materials may be used in case 3: Materials that fit the specifications of good mechanical properties, chemical resistance and dimension stability such as:
         —Fluorocarbons as ETFE that show good mechanical properties   —Nylons like PA610 special grade with lowest moisture absorption   Polyetheretherketone (PEEK) showing excellent mechanical properties   Acetals as POM, with good process ability   Polyarylene Sulfide (PAS) with good mechanical properties   Polyethersulfone (PES)   Polyimide (PI); a thermoplastic grade of the polyimide can be used for injection molding   Polyamide-imide (PAI), as Torlon (r) 465 with lower injection temperature than in case of the PI   Polyphenylene Ether (PPE) which has good process ability   Polyphenylene Sulfide (PPS) is a crystalline thermoplastic with good mechanical properties in case of grade reinforced with 40% glass fibers.       

     The fluidic conduit may or may not be filled with packing material such as beads for a chromatographic separation. Alternative filling material can be included in the fluidic channel, such as a monolithic separation material. Another configuration relates to an open tubular column. Furthermore, it is possible that no material at all is accommodated in the fluidic channel. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       Other objects and many of the attendant advantages of embodiments of the present invention will be readily appreciated and become better understood by reference to the following more detailed description of embodiments in connection with the accompanied drawings. Features that are substantially or functionally equal or similar will be referred to by the same reference signs. 
         FIG. 1  illustrates two different views of a fluidic chip device according to an exemplary embodiment. 
         FIG. 2  shows a three-dimensional view of a fluidic chip device according to an exemplary embodiment. 
         FIG. 3  to  FIG. 5  illustrate cross-sectional views of fluidic chip devices according to different exemplary embodiments. 
     
    
    
     The illustration in the drawing is schematically. 
     DETAILED DESCRIPTION 
     In the following, referring to  FIG. 1 , a fluidic chip device  100  according to an exemplary embodiment will be explained. 
     The fluidic chip device  100  is adapted as a system for carrying out liquid chromatography investigations. The fluidic chip device  100  for separating different components of a fluid or a mobile phase which can be pumped through the apparatus  100  comprises a pre-column  101  for pre-processing (for instance sample preparation or sample enrichment) the fluidic sample and comprises an analytical or main column  120  for post-processing the fluidic sample which has already passed the pre-column  101 . In other words, the system  100  is a two-stage fluid separation system. Other embodiments may include only a one-stage fluid separation system having only one column, or a multi-stage fluid separation system having multiple (for instance three, four or more) columns. 
     In the embodiment of  FIG. 1 , each of the fluid separating columns  101 ,  120  comprises a column tube  102  which is shaped to define closed packed channels, for instance having a rectangular cross-section. Within each of these fluid separating columns  101 ,  120 , a tubular reception  103  is defined which is filled with a package composition  104 . 
     The fluidic chip device  100  is adapted as a liquid chromatography device  100  and has, in each of the columns  101 ,  120 , a first frit  105  close to an inlet  131 ,  134  of the respective columns  101 ,  120 , and a second frit  106  provided at an outlet  133 ,  135  of the respective column  101 ,  120 . The first frit  105  forms the inlet of the respective column  101 ,  120  and is provided upstream the respective column tube  102 . The second frit  106  forms the outlet of the respective column  101 ,  120  and is located downstream of the respective column tube  102 . A flowing direction of the fluid which is separated using the fluidic chip device  100  is denoted with the reference numeral  109 . 
     A fluid pump  110  is provided externally from the chip  100  and pumps fluid under pressure of, for instance, 1000 bar through a connection tube  111  and from there to the inlet  131  of the pre-column  101 , through the first frit  105  into the column tube  102 . After having left the column tube  102 , that is to say after having passed the second frit  106 , an intermediate tube  132  connected to an outlet  133  of the pre-column  101  transports the pre-processed analyte to the inlet  134  of the main column  120 . The internal construction of the main column  120  is similar to that of the pre-column  101 , but may (or may not) differ from the pre-column  101  with respect to size and fluid separating material  114  filled in the tubular reception  103 . 
     In a further stage, the sample is further separated in the main column  120 , and the further separated sample leaves the outlet  135  of the main column  120 . After having left the column tube  102  of the main column  120 , that is to say after having passed the second frit  106  of the main column  120 , a second tube or pipe  112  transports the separated analyte to a container and analysis unit  113  positioned outside of the chip  100 . The container and analysis unit  113  includes cavities or containers for receiving different components of the fluid, and may also fulfill computational functions related to the analysis of the separated component(s). 
     The column tubes  102  comprises the filling  104 . In other words, a packing composition  104  comprising a plurality of silica gel beads  114  is inserted into the hollow bore  103  of the column tube  102  of each of the columns  101 ,  120 . 
     The mobile phase is first conducted through the pre-column  101 . By selecting an appropriate ACN concentration in a H 2 O environment, a fraction of the fluidic sample may first be trapped at a particular position within the column tube  102  of the pre-column  101 . This procedure may be denoted as a pre-focusing or pre-separation. Components of the mobile phase which are not trapped in the pre-column  101  are collected in a waste unit (not shown). 
     Afterwards, the ACN/H 2 O concentration ratio within the column tube  102  of the pre-column  101  may be selectively modified so as to elute the sample trapped in the column tube  102  of the pre-column  101 . Then, the fluidic sample will move through the outlet  133  of the pre-column  101 , and will enter the inlet  134  of the main column  120  to be trapped in a portion close to the outlet of the frit  105  of the main column  120 . 
     When the fluid passes through the main column  120 , components which differ from a fraction to be separated may simply pass through the column  120  without being trapped and may be collected in a waste (not shown). At the end of this procedure, a band of the fraction of the fluidic sample of interest is trapped at a particular position within the main column  120 . By again modifying the concentration ratio ACN/H 2 O, for instance by gradually modifying the respective contributions of these two components, the trapped sample may be released from the main column  120  and may be conducted to the unit  113 , for further processing. 
     Therefore, the fluidic chip  100  is adapted for processing a fluidic sample to be conducted through the fluidic chip device  100 . The fluidic chip device  100  comprises a substrate  140  which is a multilayer substrate in which various components of the fluidic chip device are integrated. 
     The described fluidic chip device  100  is shown in  FIG. 1  in a cross-sectional view along a line A-A′, as can be taken from the small illustration in  FIG. 1 . As can be taken from the small cross-sectional view, the fluidic chip device  100  is formed by the substrate  140  on and/or in which a plurality of components, as described above, such as the fluidic channel  132  is formed. However, the fluidic chip device  100  also comprises, sandwiching the substrate  140 , two reinforcing structures  162 ,  164  which are connected to one another by screws or bolts  166  passing through the plates  164 ,  162  as well as penetrating through holes  168  formed in the substrate  140 . Thus, for fastening the plates  164 ,  162  at the chip  140 , the reinforcing structures  162 ,  164  having a shape and an area being identical to a surface of the substrate  140  and having through holes aligned with the through holes  168  of the substrate  140  are connected to the substrate  140  via screws or bolts  166  inserted through the holes  168  and connected on the other side, for example by a nut (not shown) formed in components  166 . Internal threads may be provided in the through holes of the reinforcing plates  162 ,  164  and/or in the through holes  168  of the substrate  140 . 
     As can be taken from the small cross-sectional view of  FIG. 1 , the reinforcing plates  162 ,  164  have a thickness being larger than a thickness of the substrate  140 . Since they are made from steel material, they also have a higher mechanical resistance than the substrate  140  manufactured from PEEK. 
       FIG. 2  illustrates a fluidic chip device  200  according to another exemplary embodiment in a configuration for filling beads  114  into a fluidic channel  103  (not shown in  FIG. 2 ). 
     In  FIG. 2 , a lower metal plate  202  and an upper metal plate  204  basically surround or sandwich a laminated multi-layer substrate  206  comprising elements required for an HPLC application such as a fluidic channel, beads, a frit, a separation channel, etc. 
     The fluidic device  200  comprises also a fluidic sample drain opening  208  adapted to drain a fluidic sample discharging from the fluidic conduit (not shown). Thus, an appropriately shaped interface of periphery device may be connected to the drain opening  208  for further processing of the sample. 
     Moreover, a plurality of screw holes  210  are foreseen in the upper plate  204  through which the threaded metal plates  202 ,  204  may be connected by screwing, thereby encompassing the substrate  206 . An attachment piece  212  is shown as well which is adapted for inserting a separation substance (such as beads) in the fluidic conduit under pressure of, for instance several hundred bars. Thus, when beads or the like are inserted into the channel (not shown) of the substrate  206 , the reinforcing effect of the reinforcement plates  202 ,  204  prevents the multi-layer substrate  206  from delamination or other undesired effects, thereby preventing leaking or deterioration of the substrate  206 . 
       FIG. 3  shows a cross-sectional view of a fluidic chip device  300  according to another exemplary embodiment. 
     As can be taken from  FIG. 3 , a multi-layer substrate  206  comprises a lower layer  302 , a middle layer  304  having a fluidic channel  103  filled with beads  114 , and an upper layer  306 . The layers  302 ,  304  and  306  are connected to one another by lamination, for instance using glue in their connection portions. A through hole is formed through each of components  302 ,  304 ,  306  so that a screw  308  can be guided through the aligned through holes, and can be fixed at another end using screw nuts  310 , which may be connected to the screw  308  by actuating corresponding screw recesses  312  by a screw driver or the like. A traction connection is thus formed between the reinforcing structures  202 ,  204  on the one hand and the guide elements  308 ,  310  on the other hand. 
       FIG. 3  also shows exemplary dimensions of the various components. An extension d may be 25 mm. An extension l may be between 10 μm and 0.5 mm. A thickness s may be 5 mm. A thickness b may be 100 μm. 
       FIG. 4  shows a fluidic chip device  400  according to another exemplary embodiment. 
     In the fluidic chip device  400 , a five layer laminated substrate is constituted by a first layer  402 , a second layer  404 , a third layer  406 , a fourth layer  408  and a fifth layer  410 . In the fourth layer  408 , a channel  103  is formed and is filled with beads  114 . In the second layer  404 , a separation channel  424 ,  416  is formed. Electrodes  418 ,  420  are formed in the third layer  406  which can be used for promoting the sample transport or separation procedure. The upper and lower layers  402 ,  410  do not comprise any elements contributing to the fluid separation. 
     An upper enforcement element  412  and a lower enforcement element  414  are arranged to fit to one another and to enclose an accommodation space which completely surrounds the multi-layer structure  402 ,  404 ,  406 ,  408 ,  410  in a tight manner. Thus, even when a high pressure is applied to insert beads  114  into the channel  103  and/or while pumping a fluidic sample through any one of the structures  103 ,  424 ,  416 , the encompassing reinforcement structures  412 ,  414  provide a counterforce preventing delamination of the substrate  402 ,  404 ,  406 ,  408 ,  410 . The reinforcement structures  412 ,  414  may be fastened at facing surfaces  422  by adhering. Additionally or alternatively, the structures  412 ,  414  may be made of a magnetic material generating an attracting force between the structures  412 ,  414 , thereby firmly but reversibly connecting the structures  412 ,  414  based on a magnetic force, thereby simultaneously enclosing the multi-layer substrate  402 ,  404 ,  406 ,  408 ,  410 . 
     The attracting magnetic force may be formed between permanent magnetic structures  412 ,  414 . Alternatively, a selectively attracting or repulsive (for separating components  412 ,  414 ) magnetic force may be formed between magnetic structures  412 ,  414  when implementing them as an electromagnet structure being operable or switchable by an electric signal. 
       FIG. 5  illustrates a fluidic device  500  according to still another exemplary embodiment. 
     In the embodiment of  FIG. 5 , a two-layer substrate  502  is formed by a first layer  504  and a second layer  506 . Both layers  504 ,  506  comprise a through hole into which protrusions  508 ,  510  of an upper reinforcement plate  512  extend. These protrusions  508 ,  510  are received in correspondingly shaped grooves of a grooved second reinforcement plate  514 , thereby forming a non-positive locking. 
     The second layer  506  comprises a fluidic channel  132  which, via a through hole  516  in the first layer  504  and a corresponding through hole  518  in the upper reinforcement structure  512 , is in fluid communication with a further fluidic channel  520  in an upper cover layer  522 . Furthermore, a lower cover layer  524  is connected to the reinforcement structure  514 . Thus, in the embodiment of  FIG. 5 , the reinforcement structures  512 ,  514  are embedded between fluidic chip layers  504 ,  506  on the one hand and cover layers  522 ,  524  on the other hand. 
     It should be noted that the term “comprising” does not exclude other elements or features and the “a” or “an” does not exclude a plurality. Also elements described in association with different embodiments may be combined. It should also be noted that reference signs in the claims shall not be construed as limiting the scope of the claims.