Flow cell, optical module and spectrometer for optical measurement

Abstract

A flow cell for optical measurement comprises a base body 1 having an inlet 2 and an outlet 3 and an aperture 4 arranged at a first outer side of the base body, where a recess 5 is provided at the first outer side of the base body, which recess contains a flow cell measurement chamber connected to the inlet and the outlet. The flow cell further comprises means clamped between the aperture and the at least one first wall region of the recess, the means comprising an ATR crystal 7 and a sealing element 8 for sealing the measurement chamber of the flow cell. The material of the base body and the material of the aperture differ in that the thermal expansion coefficients thereof differ, and the aperture can be fixed at a first fixing point on the base body by means of a first fixing member. The base body and the aperture cannot move relative to each other in the x direction running parallel to the first outer side of the base body, in the y direction running parallel to the first outer side of the base body and in the z direction running perpendicular to the first outer side of the base body at the first fixing part. The aperture can be fastened to the base body at a second fastening point by means of a second fastening means 10 such that the base body and the aperture cannot move relative to each other in the z-direction at the second fastening point and can only move relative to each other to some extent in the x-direction and in the y-direction. In this way, different expansion and / or contraction of a component of the flow chamber occurring upon a temperature change can be compensated. In addition or alternatively, the flow chamber comprises a filter element 15 arranged in the recess between the ATR crystal and the opening connected to the inlet and / or between the ATR crystal and the opening connected to the outlet.

Description

[0001] The present invention relates to a flow cell for optical measurements. The flow cell comprises a base body having at least one inlet and at least one outlet for a substance to be measured and an aperture arranged at a first outer side of the base body, wherein at the first outer side of the base body a recess is provided, which contains a flow cell measurement cavity connected with the at least one inlet and the at least one outlet. The flow cell comprises a device clamped between the aperture and at least one first wall region of the recess, which device comprises an ATR crystal and at least one first sealing element for sealing the flow cell measurement cavity, wherein the at least one first sealing element is arranged at a side of the ATR crystal facing away from the aperture. The present invention further relates to an optical module comprising a flow cell according to the present invention, and to a spectrometer comprising the optical module.

[0002] Over the past decades, the interest in integrated continuous bioprocesses has grown, driving the development and introduction of process analytical technology (PAT) that enables real-time monitoring of key process parameters. The aim of adapting to continuous processing is to better understand the process. This leads to a reduction of production cycle times and ultimately to an increase in yield and productivity.

[0003] Protein concentration is an essential parameter that has to be monitored in downstream processes. Therefore, there is an increasing need to transfer the measurement of protein concentration from offline analysis to online analysis. For this purpose, spectroscopic techniques have proven to be a powerful analytical tool enabling continuous and simultaneous monitoring of key quality characteristics, in particular concentrations of metabolites, nutrients and auxiliary materials.

[0004] For optical or spectroscopic measurements of online analysis, a flow cell can be used as a component of an optical module of a spectrometer. Thereby, a portion of a reaction mixture can be led out of a reactor during the process, subsequently be guided through the flow cell and then be led back into the reactor, wherein the reaction mixture, while being guided through the flow cell, is subjected to an optical or spectroscopic measurement within a measurement cavity of the flow cell to determine, for example, concentrations of metabolites, nutrients and auxiliary materials in the reaction mixture.

[0005] Problems in such measurements can mainly be caused by contamination with microorganisms, such as bacteria, viruses or fungal spores, or by deposition of microorganisms, biomolecules or cell residues in the measurement cavity of the flow cell. Thus, microorganisms entering the measurement cavity of the flow cell from the outside can be guided together with the reaction mixture to be measured into the reactor, leading to contamination of the reactor and of the reaction products produced therein. Furthermore, deposition of microorganisms, biomolecules or cell residues in the measurement cavity of the flow cell can lead to a deterioration of the optical measurement.

[0006] Based on this, it is an object of the present invention to provide a flow cell for optical measurements with which contamination of the measurement cavity of the flow cell and / or of the substance measured therein can be better avoided.

[0007] This object is achieved by a flow cell having the features of claim 1, by an optical module having the features of claim 12 and by a spectrometer having the features of claim 15. The respective dependent claims represent advantageous refinements.

[0008] According to the present application, therefore, a flow cell for optical measurement (or for use in optical measurement) is proposed, which comprises a base body having at least one inlet (for a substance to be measured) and at least one outlet (for a substance that has been measured) and an aperture arranged at a first outer side of the base body, wherein a recess is provided at the first outer side of the base body, which recess contains a flow cell measurement cavity which is (fluidically) connected to the at least one inlet and the at least one outlet, wherein the base body can preferably consist of at least one material having a first coefficient of thermal expansion and the aperture can consist of at least one material having a second coefficient of thermal expansion which differs from the first coefficient of thermal expansion.

[0009] The first and second coefficients of thermal expansion can be determined, for example, by dilatometry, for example according to ISO 11359-2:2021-11.

[0010] Preferably, the second coefficient of thermal expansion differs from the first coefficient of thermal expansion by at least 10 · 10 -6 K -1 , more preferably by at least 20 · 10 -6 K -1 , particularly preferably by at least 50 · 10 -6 K -1 , very preferably by at least 80 · 10 -6 K -1 , for example by 80 · 10 -6 K -1 to 200 · 10 -6 K -1 .

[0011] The flow cell further comprises a device clamped between the aperture and at least one first wall region of the recess (facing the aperture), which device comprises an ATR crystal and at least one first sealing element for sealing the flow cell measurement cavity, wherein the at least one first sealing element is arranged on a side of the ATR crystal facing away from the aperture.

[0012] Here, an ATR crystal is understood to be an element which can be used as an ATR crystal or ATR element in ATR infrared spectroscopy (ATR = "attenuated total reflection").

[0013] It is provided that:

[0014] - the base body consists of at least one material having a first coefficient of thermal expansion and the aperture consists of at least one material having a second coefficient of thermal expansion which differs from the first coefficient of thermal expansion, wherein the aperture is fixable at the base body at at least one first fixing site by at least one first fixing means such that the base body and the aperture are substantially immovable relative to each other in an x-direction which extends parallel to a first outer side of the base body, in a y-direction which extends parallel to the first outer side of the base body and in a z-direction which extends perpendicular to the first outer side of the base body at the at least one first fixing site, and wherein the aperture is fixable at the base body at at least one second fixing site by at least one second fixing means such that the base body and the aperture are substantially immovable relative to each other in the z-direction at the at least one second fixing site and are movable relative to each other in the x-direction and in the y-direction, respectively, only to a certain extent, such that different expansions and / or contractions of components of the flow cell which occur upon temperature changes can be compensated for,

[0015] and / or

[0016] - the flow cell comprises at least one filter element which is arranged in the recess between the ATR crystal and at least one opening which is connected to the at least one inlet and / or between the ATR crystal and at least one opening which is connected to the at least one outlet.

[0017] The aperture is fixable or fixed at the base body at at least one first fixing site by at least one first fixing means such that the base body and the aperture are substantially immovable relative to each other in an x-direction which extends parallel to a first outer side of the base body, in a y-direction which extends parallel to the first outer side of the base body (and which extends perpendicular to the x-direction) and in a z-direction which extends perpendicular to the first outer side of the base body at the at least one first fixing site. Herein, "substantially immovable relative to each other" can be understood such that the base body and the aperture are movable relative to each other in the x-direction, in the y-direction and in the z-direction, respectively, at the at least one first fixing site by less than 10 pm, preferably by at most 9 pm, particularly preferably by at most 5 pm, very particularly preferably by at most 1 pm. Particularly preferably, the base body and the aperture are completely immovable relative to each other in the x-direction, in the y-direction and in the z-direction, respectively, at the at least one first fixing site.

[0018] Furthermore, the aperture can be fixed or fixed at the base body at at least one second fixing site by at least one second fixing element, such that the base body and the aperture are substantially immovable relative to each other in the z-direction at the at least one second fixing site and are only movable relative to each other to a certain extent in the x-direction and in the y-direction, respectively, such that different expansions and / or contractions of components of the flow cell, in particular of the base body and the aperture, which occur upon a temperature change, preferably up to 80 K, particularly preferably up to 120 K, for example a temperature change of from 10 K to 130 K, can be compensated (or can be compensated such that the temperature change does not lead to a bending of the components of the flow cell, in particular of the base body and the aperture, or leads to a bending of at most 0.1 mm). Here, "substantially immovable relative to each other" is understood to mean that the base body and the aperture are movable relative to each other in the z-direction at the at least one second fixing site by less than 10 pm, preferably at most 9 pm, particularly preferably at most 5 pm, very particularly preferably at most 1 pm. Particularly preferably, the base body and the aperture are completely immovable relative to each other in the z-direction.

[0019] The bending value of a component, for example of the base body and / or of the aperture, can be determined here as the distance between a point of the component which lies in the un-bent state at the midpoint of the direct connection line between the first fixing site and the second fixing site and the same point of the component in the bent state.

[0020] The base body and the aperture can consist of different materials, i.e. the aperture can consist of a different material than the base body, such that the material of the aperture has a different coefficient of thermal expansion than the base body material. By implementing a flow cell having a base body and an aperture made of different materials, the individual regions of the flow cell can be better adapted to the respective specific requirements than in a flow cell in which the base body and the aperture are realized in a single element from one material.

[0021] The base body can comprise a flow structure, for example a channel structure, through which the substance to be measured or the measured substance is guided through the flow cell (or from the inlet to the flow cell measurement chamber and from the flow cell measurement chamber to the outlet). The base body can preferably be a polymer base body, for example a thermoplastic base body, which can be produced, for example, by 3D printing. In this way, a base body having a suitable, possibly complex channel structure can be realized in a simple and inexpensive manner.

[0022] The aperture can serve as a connecting element of the flow cell to the module body of the optical module. Here, the aperture can be made of a material which is harder than the base body, preferably an alloy, for example stainless steel, such that a very firm connection of the flow cell to the module body can be achieved in this way and a sealing element for sealing the connection between the flow cell and the module body can be sealed well.

[0023] The aperture is located on a first outer side of the substrate, and a recess containing the flow chamber measurement cavity is also located on this first outer side. Therefore, the recess with the flow chamber measurement cavity is adjacent to the aperture. In this aperture region, an aperture ring can be implemented such that the aperture ring is adjacent to the recess.

[0024] A device comprising an ATR crystal and at least one first sealing element for sealing the flow chamber measurement cavity is clamped between the aperture and at least one first wall region of the recess (facing the aperture), wherein the at least one first sealing element is arranged on the side of the ATR crystal opposite to the aperture. Thus, the flow chamber cavity can be configured such that it is defined by the ATR crystal, the at least one first sealing element, and the wall region of the recess. By fixing the aperture to the substrate, the device comprising the ATR crystal and at least one first sealing element for sealing the flow chamber measurement cavity can be clamped between the aperture and at least one first wall region of the recess (facing the aperture), thereby achieving a seal for the flow chamber cavity.

[0025] When the substrate and pore size (and possibly the ATR crystal and / or at least one first sealing element) are composed of materials with different coefficients of thermal expansion, drastic temperature changes (e.g., during sterilization or autoclaving of the flow chamber) will cause different expansions in the components (i.e., the substrate and pore size, and possibly the ATR crystal and / or at least one first sealing element). If the pore size is fixed to the substrate such that the substrate and pore size are substantially immobile relative to each other in all three spatial directions (i.e., the x, y, and z directions) at all fixed locations, the different expansions in the components will cause stresses that will cause bending of the components. This bending will cause the clamped device, including the ATR crystal and at least one first sealing element, to loosen, ultimately resulting in unsealed areas in the device. At these unsealed areas, the flow chamber measuring cavity is no longer adequately sealed, allowing the reaction mixture to reach the outside through the unsealed areas, and allowing contaminants or microorganisms to enter the flow chamber cavity from the outside through the unsealed areas.

[0026] This situation can be prevented by specifically fixing the aperture at the substrate. Here, the aperture can be fixed at at least one first fixing point at the substrate by at least one first fixing member, such that the substrate and the aperture are substantially immobile relative to each other in all three spatial directions (i.e., the x, y, and z directions) at the at least one first fixing point. The aperture can be fixed at at least one second fixing point at the substrate by at least one second fixing member, such that the substrate and the aperture are substantially immobile relative to each other only in the z direction at the at least one second fixing point, and can only move relative to each other to a certain extent in the x and y directions respectively. This allows for compensation of the different expansion and / or contraction of the components of the flow chamber that occur during temperature changes. Therefore, at least one second fixing member ensures a certain degree of mobility between the substrate and the aperture relative to each other in the x and y directions, through which different expansion and / or contraction of the components can be compensated. Therefore, during drastic temperature changes (e.g., during sterilization or autoclaving of the flow chamber), although different expansion of the components still occurs, this (due to a certain degree of mobility in the x and y directions) no longer causes bending of the components, thus preventing loosening of the clamped device, including the ATR crystal and at least one first sealing element. In this way, unsealed areas are thus prevented in the device where the flow chamber measuring cavity is no longer adequately sealed. Therefore, even during drastic temperature changes (e.g., during sterilization or autoclaving of the flow chamber), the flow chamber maintains a high degree of sealing, preventing contaminants from entering the flow chamber cavity from the outside through unsealed areas. Therefore, contamination of the flow chamber cavity and the substance measured therein by external contaminants or microorganisms can be better avoided.

[0027] The flow chamber may include at least one filter element arranged in a recess between the ATR crystal and at least one opening connected to at least one inlet and / or between the ATR crystal and at least one opening connected to at least one outlet. The objectives of the invention can also be achieved in this manner, as described below.

[0028] The analyte guided through the flow chamber may contain large molecules (such as proteins), cellular residues, and microorganisms. These substances may deposit on the ATR crystal, leading to biocontamination. Deposits or biocontamination can further degrade measurements because the deposited components contribute an excessively large signal in the measurement or measurement spectrum, thus affecting measurement quality. Furthermore, deposits on the ATR crystal can contaminate the analyte at that location in subsequent measurements.

[0029] By using at least one filter element arranged in the recess between the ATR crystal and at least one opening connected to at least one inlet, larger molecules (e.g., proteins), cellular residues, and microorganisms contained in the analyte can be kept away from the ATR crystal because these components are trapped by the filter element, while the liquid containing smaller molecules relevant for optical measurement passes through the filter element. Therefore, deposits or biocontamination on the ATR crystal can be better avoided. Thus, contamination of the flow chamber and (in the future) the analyte within it can be better prevented by the filter element.

[0030] In addition, the filter element can also keep air bubbles in the analyte away from the ATR crystal. These air bubbles, when attached to the ATR crystal, can also have an undesirable effect on the measurement or the measurement spectrum.

[0031] Advantageously, the flow chamber according to the invention can be used as a replaceable and / or disposable product. Preferably, the flow chamber according to the invention is a replaceable and / or disposable product. The replaceable flow chamber allows for sterilization and replacement because the surface of the ATR crystals becomes rapidly contaminated during biological processes.

[0032] Instead of fixing the aperture to the substrate by at least one first fastener and at least one second fastener, the aperture can also be secured to the substrate in other ways. For example, the aperture can be secured (or bonded) to the substrate by means of at least one adhesive material.

[0033] A preferred embodiment of the flow chamber according to the invention is characterized in that the aperture is fixed at at least one second fixed location on the substrate by at least one second fixing member, such that the substrate and the aperture are substantially immobile relative to each other in the z-direction at the at least one second fixed location, and are respectively capable of relative movement of at least 0.01 mm, preferably at least 0.05 mm, particularly preferably at least 0.1 mm, and / or at most 1 mm, preferably at most 0.8 mm, particularly preferably at most 0.5 mm, in the x-direction and y-direction. Here, "substantially immobile relative to each other" can be understood as the substrate and the aperture being able to move relative to each other in the z-direction at the at least one second fixed location by less than 10 µm, preferably at most 9 µm, particularly preferably at most 5 µm, and extremely preferably at most 1 µm. Particularly preferably, the substrate and the aperture are completely immobile relative to each other in the z-direction.

[0034] Another preferred embodiment of the flow chamber according to the invention is characterized in that,

[0035] - At least one first fastener is selected from the group consisting of countersunk screws and combinations thereof, wherein at least one first fastener is preferably at least one countersunk screw, and / or

[0036] - At least one second fastener is selected from the group consisting of a semi-circular head screw, a rivet, a cylindrical head screw, and combinations thereof, wherein at least one first fastener is preferably at least one semi-circular head screw.

[0037] With these specific fasteners, the desired immobility can be easily achieved in all three spatial directions at at least one first fixed location and in the z-direction at at least one second fixed location, and the desired limited mobility in the x and y directions at at least one second fixed location.

[0038] Another preferred embodiment of the flow chamber according to the invention is characterized in that at least one material constituting the matrix is ​​at least one polymer, particularly preferably at least one thermoplastic polymer. Most preferably, the material constituting the matrix is ​​at least one polymer selected from the group consisting of polyetheretherketone, polytetrafluoroethylene, polypropylene, polysulfone, polyethersulfone, polycarbonate, polyvinyl chloride, polylactic acid, polyamide, thermoplastic polyurethane, acrylonitrile-butadiene-styrene, UV-curable (autoclaveable) synthetic resins, and mixtures thereof. In this case, the matrix can be manufactured in a simple and inexpensive manner by 3D printing. Flow or channel structures can be easily achieved here. For example, at least one material constituting the matrix may comprise bisphenol A-dimethacrylate, 2-hydroxyethyl methacrylate, and urethane dimethacrylate, or a combination thereof. For example, the product "BioMed Clear" from formlabs can be used as the material for the matrix.

[0039] In another preferred embodiment of the flow chamber according to the invention, at least one material constituting the aperture is selected from: metals, such as iron; alloys, preferably iron-containing alloys, such as stainless steel; polymers, such as polyetheretherketone; and mixtures and combinations thereof, wherein the aperture preferably comprises stainless steel or is composed of the like. In this way, a very robust connection can be achieved between the flow chamber and the module body of the optical module, enabling the sealing element used to seal the connection between the flow chamber and the module body to provide a good seal.

[0040] Another preferred embodiment of the flow chamber according to the invention is characterized by an ATR crystal.

[0041] - Contains or is composed of at least one material that is at least partially transparent to light with wavelengths of 2µm to 20µm, preferably 4µm to 12µm, wherein the ATR crystal preferably contains or is composed of at least one material selected from the group consisting of silicon, diamond, germanium, zinc selenide, zinc sulfide, and mixtures and combinations thereof, wherein the ATR crystal particularly preferably contains or is composed of silicon, and / or

[0042] - Includes multiple microprisms, and / or

[0043] - A structured portion is provided on the side facing the aperture, preferably a structured portion with grooves or recesses, and particularly preferably a structured portion with V-shaped grooves or recesses.

[0044] The transparency of at least one material contained in or composed of an ATR crystal can be determined, for example, according to DIN 4522-4:1993-04.

[0045] Preferably, the ATR crystal comprises or is composed of at least one partially transparent material having a transmittance greater than 10% for light with wavelengths from 2 μm to 20 μm, preferably from 4 μm to 12 μm. The transmittance can be determined, for example, according to DIN 4522-4:1993-04.

[0046] High light throughput can be achieved while reducing positioning accuracy using microprisms. Structured elements with grooves or recesses can simplify light coupling and reduce positioning accuracy.

[0047] Another preferred embodiment of the flow chamber according to the invention is characterized in that,

[0048] - At least one first sealing element

[0049] • Contains or consists of at least one polymer selected from: the group consisting of ethylene-propylene-diene rubber, silicone, and mixtures thereof, and / or

[0050] • Constructed in the form of a circular ring, and / or

[0051] • Sealing contact with at least one first wall region of the ATR crystal and / or recess.

[0052] and / or

[0053] - The flow chamber includes at least one second sealing element arranged around the recess, wherein the at least one second sealing element preferably

[0054] • Contains or consists of at least one polymer selected from: the group consisting of ethylene-propylene-diene rubber, silicone, and mixtures thereof, and / or

[0055] • Constructed in the form of a circular ring, and / or

[0056] • At least partially arranged in a separate recess, which is arranged around the recess and positioned on the first outer side of the substrate, and / or

[0057] • Seal contact with the substrate and / or pore size.

[0058] A good seal of the flow chamber measuring cavity can be easily achieved by at least one first sealing element comprising or consisting of at least one polymer selected from the group consisting of ethylene-propylene-diene rubber, silicone, and mixtures thereof, and / or configured in the form of a circular ring, and / or sealingly contacting at least one first wall region of the ATR crystal and / or the recess. It should be noted that, in principle, it is also feasible for at least one first sealing element not to contact at least one first wall region of the ATR crystal and / or the recess, i.e., for example, when another element is arranged between at least one first sealing element and the ATR crystal or between at least one first sealing element and at least one first wall region of the recess.

[0059] At least one second sealing element can ensure that no gas enters the region (e.g., cavity) between the ATR crystal and the aperture from the environment.

[0060] Another preferred embodiment of the flow chamber according to the invention is characterized in that the flow chamber includes at least one filter element arranged in a recess between an ATR crystal and at least one opening connected to at least one inlet (and / or between an ATR crystal and at least one opening connected to at least one outlet), wherein preferably, at least one filter element

[0061] - Selected from: the group consisting of cellulose filter elements, such as filter elements made of regenerated cellulose; paper filter elements; glass fiber filter elements; cellulose acetate filter elements; polyethersulfone filter elements; nylon filter elements; polyvinylidene fluoride filter elements; polytetrafluoroethylene filter elements; polypropylene filter elements; polycarbonate filter elements; and combinations thereof, wherein at least one filter element is preferably selected from: the group consisting of cellulose filter elements, paper filter elements, glass fiber filter elements, and combinations thereof, and / or

[0062] - It has a thickness of 0.001mm to 5mm, preferably 0.01mm to 1mm, and particularly preferably 0.02mm to 0.2mm.

[0063] The analyte guided through the flow chamber may contain larger molecules (e.g., proteins), cellular residues, and microorganisms. These substances can deposit on the ATR crystal, leading to biocontamination. Deposits or biocontamination can then degrade measurements because the deposited components contribute an excessively large signal in the measurement or spectrum, thus affecting measurement quality. Furthermore, deposits on the ATR crystal can contaminate the analyte in subsequent measurements. By using a filter element, larger molecules (e.g., proteins), cellular residues, and microorganisms in the analyte are kept away from the ATR crystal, as these components are trapped by the filter element, while smaller molecules relevant for optical measurements pass through. Therefore, the filter element better prevents contamination of the flow chamber and the analyte (to be measured) within it. Additionally, the filter element keeps air bubbles present in the analyte away from the ATR crystal; these bubbles, when attached to the ATR crystal, can also have undesirable effects on the measurement or spectrum.

[0064] For at least one filter element, various materials can be used, preferably selected from: the group consisting of cellulose, such as regenerated cellulose; paper; glass fiber; cellulose acetate; polyethersulfone; nylon; polyvinylidene fluoride; polytetrafluoroethylene; polypropylene; polycarbonate; and combinations thereof. Cellulose acetate exhibits good chemical resistance and low protein binding. Polyethersulfone (PES) achieves high flow rates and low protein binding. Nylon possesses high mechanical strength and good chemical resistance. Polyvinylidene fluoride (PVDF) exhibits high chemical stability and low protein binding. Polytetrafluoroethylene (PTFE) has excellent chemical resistance and is suitable for use with corrosive solvents. Polypropylene is chemically stable and has lower protein binding compared to other materials. Regenerated cellulose (RC) exhibits good chemical resistance and low protein binding. Polycarbonate can be used for track-etched membranes with uniform pore size.

[0065] Alternatively, the flow chamber may not have a filter element arranged in the recess between the ATR crystal and at least one opening connected to at least one inlet and / or between the ATR crystal and at least one opening connected to at least one outlet.

[0066] Another preferred embodiment of the flow chamber according to the invention is characterized in that the flow chamber further includes at least one filter holder for holding at least one filter element, the at least one filter holder being arranged between the ATR crystal and the at least one filter element, wherein the at least one filter holder preferably has a grid structure and a frame extending around the grid structure. Particularly preferred herein is...

[0067] - The frame is in contact with the ATR crystal, while the grid structure is not in contact with the ATR crystal. The grid structure is preferably arranged at a distance of 0.001 mm to 5 mm, more preferably 0.005 mm to 2 mm, particularly preferably 0.008 mm to 1 mm, and extremely preferably 0.01 mm to 0.1 mm from the ATR crystal.

[0068] - At least one filter element is held between the frame and at least one second wall region of the recess facing the aperture, and / or

[0069] - The central wall region of the recess facing the aperture has at least one retaining element, preferably at least two retaining elements, wherein at least one filter element is held between the grid structure and at least one retaining element.

[0070] The filter element can be positioned at a favorable distance from the ATR crystal using a filter retainer, ensuring that the filter does not contact the ATR crystal and thus does not interfere with optical measurements. Here, the grid structure effectively prevents the central region of the filter, wetted by the analyte, from sagging and contacting the ATR crystal. The filter is also better secured by at least one retainer in the central wall region of the recess, thus better preventing filter slippage.

[0071] Another preferred embodiment of the flow chamber according to the invention is characterized in that at least one filter element is arranged in direct contact with at least one photoresist coating applied to the ATR crystal, wherein preferably...

[0072] - At least one photoresist coating has a thickness of 0.1µm to 100µm, preferably 1µm to 50µm, particularly preferably 5µm to 20µm, and / or

[0073] - At least one photoresist coating is applied to the ATR crystal in the form of a grid or strip, wherein the arrangement of the photoresist coating on the ATR crystal is preferably adapted to the structured portion of the ATR crystal, which has the structured portion on the side of the ATR crystal facing the aperture, and / or

[0074] - At least one filter element is fastened to at least one first sealing element, preferably in a material-fit manner to at least one first sealing element.

[0075] For the photoresist coating, photoresists commonly used in the prior art can be used. Photoresists allow for very precise and thin coatings. Therefore, with a photoresist coating, the filter element can be placed at a very small advantageous distance from the ATR crystal, ensuring that, on the one hand, the filter does not contact the ATR crystal and thus does not interfere with optical measurements; on the other hand, only a very small amount of liquid exists between the ATR crystal and the filter element, resulting in a very short diffusion time, which greatly improves measurement speed (or reduces time delay). By applying at least one photoresist coating to the ATR crystal in the form of a grid or strip, interference of the photoresist coating on optical measurements can be prevented or at least minimized. Particularly preferably, the arrangement of the photoresist coating on the ATR crystal can be adapted to a structured portion of the ATR crystal, having this structured portion on the aperture-facing side, such that the photoresist coating is applied only to locations where the optical beam (e.g., an infrared beam) will not reach during optical measurements. For example, if the ATR crystal has a structured portion with grooves or recesses on the side facing the aperture, the photoresist coating can be applied, for example, only to those strip-shaped portions (on the opposite side of the ATR crystal) that extend along these grooves or recesses.

[0076] For example, the optical path can be selected by the geometry (of the ATR crystal or a structured portion present on the ATR crystal) such that unilluminated areas are created on the upper side of the ATR crystal. Spacer holders (e.g., photoresist coatings or filter holders) can be applied to these areas. These spacer holders can be manufactured using various methods, such as photolithography, 3D printing, or CNC / CAM (CNC = "Computer Numerical Control"; CAM = "Computer-Aided Manufacturing"). A filter (or an actual filter membrane) can be applied to the spacer holder.

[0077] Another preferred embodiment of the flow chamber according to the invention is characterized in that at least one filter element is arranged in direct contact with at least one spacer member arranged, preferably applied to the ATR crystal, wherein preferably

[0078] - At least one spacer retainer has a thickness of 0.1µm to 100µm, preferably 1µm to 50µm, particularly preferably 5µm to 20µm, and / or

[0079] - At least one spacer is applied to the ATR crystal in the form of a grid or strip, wherein the arrangement of the spacer on the ATR crystal is preferably adapted to the structured portion of the ATR crystal, which has the structured portion on the aperture-facing side (e.g., adapted such that it is arranged only in those areas where the structured portion (or the geometry of the structured portion) of the ATR crystal will not be reached (or illuminated) by the optical beam during optical measurement), and / or

[0080] - At least one spacer retainer is fastened to at least one first sealing element, preferably connected to at least one first sealing element in a material-fit manner, and / or

[0081] - A spacer holder can be manufactured or produced by a method selected from the group consisting of photolithography, 3D printing, CNC (“Computer Numerical Control”), and combinations thereof, and / or

[0082] - At least one spacer is at least one photoresist coating, and / or

[0083] - Only in areas that will not be reached (or illuminated) by the optical beam during optical measurement due to the structured portion (or geometry of the structured portion) of the ATR crystal, the ATR crystal having the structured portion on the side facing the aperture.

[0084] There are several possibilities for implementing the spacer holders. For example, trenches can be etched into the wafer in the area irradiated by the beam to obtain raised strips that serve as spacer holders for the filter. Alternatively, strips can be applied to optically inactive regions. These strips can be fabricated using photoresist, precision films, or micro-3D printing. It is also conceivable that the strips are very fine, periodically arranged lines. The second variant (i.e., applying strips to optically inactive regions) is more advantageous here because any etching of the surface would roughen it, thus introducing optical problems.

[0085] Furthermore, it is also feasible in principle to arrange at least one filter element in direct contact with at least one ATR crystal, i.e., there is no distance between the filter element and the ATR crystal. In this case, neither a filter holder nor a photoresist coating is required.

[0086] Another preferred embodiment of the flow chamber according to the invention is characterized by a recess.

[0087] - Arranged between at least one first fixing portion and at least one second fixing portion, wherein the at least one first fixing portion and at least one second fixing portion preferably have the same distance from the recess, and / or

[0088] - The central wall region of the recess facing the aperture has a structured portion, preferably a serrated structured portion, and / or

[0089] - The central wall region of the recess facing the aperture has at least one opening connected to at least one inlet, and / or

[0090] - The central wall region of the recess facing the aperture has at least one opening connected to at least one outlet.

[0091] The (serrated) structured section can better prevent biocontamination on the filter element.

[0092] By arranging a recess between at least one first fixing location and at least one second fixing location, or by arranging the fixing locations (together with the fixing element) such that the recess (and therefore the flow chamber measuring cavity) is located between two fixing locations, particularly in the exact center between the two fixing locations, a particularly good fixation and a particularly high sealing performance of the flow chamber measuring cavity can be achieved. Preferably, the distance between at least one first fixing location and at least one second fixing location is 5 mm to 100 mm, more preferably 15 mm to 50 mm, and particularly preferably 20 mm to 40 mm. Preferably, the distance between at least one first fixing location and the recess and / or the distance between at least one second fixing location and the recess is 2 mm to 50 mm, more preferably 7 mm to 25 mm, and particularly preferably 10 mm to 20 mm.

[0093] Another preferred embodiment of the flow chamber according to the invention is characterized in that the flow chamber includes at least one third fastener, preferably a separate third fastener, for securing the flow chamber to the module body of the optical module, wherein

[0094] - At least one third fastener has a main extending direction, wherein the angle between the main extending direction and the first outer side of the base is 20° to 85°, preferably 30° to 70°, particularly preferably 40° to 65°, and / or

[0095] - At least one third fastener is selected from the group consisting of head screws, round head screws, and combinations thereof, wherein the at least one third fastener is preferably at least one head screw, particularly preferably a single head screw, and / or

[0096] - The aperture has a protruding area that extends beyond the second outer side of the substrate (adjacent to the first outer side of the substrate), wherein the recess is preferably arranged between the second outer side of the substrate and at least one third fastener, and / or

[0097] - The flow chamber also has at least one third sealing element, which is arranged around at least one third fastener and is sealed to at least one third fastener.

[0098] The flow chamber can be easily and securely connected to the main body of the optical module using the third fastener.

[0099] Preferably, at least one third sealing element

[0100] - Contains or consists of at least one polymer selected from: the group consisting of ethylene-propylene-diene rubber, silicone, and mixtures thereof, and / or

[0101] - It is formed in the form of a circular ring.

[0102] The present invention also relates to an optical module, including a module body and a flow chamber according to the invention, the flow chamber being fastened to the module body.

[0103] A preferred embodiment of the optical module according to the invention is characterized in that the flow chamber is fastened to the module body by at least one third fastener, preferably a separate third fastener, and a stop element disposed on the outer side of the module body facing the flow chamber, wherein the stop element has a stop surface, the flow chamber is pressed against the stop surface by at least one third fastener, and wherein preferably...

[0104] - The angle between the stop surface and the first outer side of the substrate is 20° to 85°, preferably 30° to 65°, particularly preferably 40° to 50°, and / or

[0105] - At least one third fastener has a main extending direction, wherein the angle between the main extending direction and the first outer side of the base is 20° to 85°, preferably 30° to 70°, particularly preferably 40° to 65°, and / or

[0106] - At least one third fastener is selected from the group consisting of head screws, round head screws, and combinations thereof, wherein the at least one third fastener is preferably at least one head screw, particularly preferably a single head screw, and / or

[0107] - The aperture has a protruding region that extends beyond the second outer side of the substrate (adjacent to the first outer side of the substrate), wherein the protruding region presses against the stop surface, and wherein the recess is preferably arranged between the second outer side of the substrate and at least one third fastener, and / or

[0108] - The flow chamber also has at least one third sealing element, which is arranged around at least one third fastener and is sealed to at least one third fastener.

[0109] The flow chamber can be easily and securely connected to the module body using a third fastener and a stop element. Here, the third fastener can be installed at an angle to the first outer side of the base, causing the flow chamber to press against the module body and the stop surface of the stop element at an angle; that is, the first force component is directed towards the module body, and the second force component is directed towards the stop surface. The stop surface can now be arranged at a corresponding angle to the first outer side of the base to effectively absorb the force component applied to the stop surface by the fastener and redirect it towards the module body. This method achieves a very secure fixation.

[0110] A preferred embodiment of the optical module according to the present invention is characterized in that the module body...

[0111] - Includes (separate) lenses for coupling the input beam incident on the ATR crystal and for coupling the output beam reflected from the ATR crystal, wherein the lenses preferably contain or are composed of zinc selenide, and / or

[0112] - Includes an optical window disposed between the ATR crystal and the lens, wherein the optical window preferably comprises or is composed of zinc sulfide, and / or

[0113] - Includes at least one fourth sealing element, which is arranged on the outer side of the module body facing the flow chamber and makes sealing contact with the side of the flow chamber facing the module body, wherein the at least one fourth sealing element is configured in the form of a circular ring, and / or

[0114] - Includes a polarizer for polarizing the beam reflected from the ATR crystal and subsequently coupled out.

[0115] The advantage of using separate lenses for optical input and output coupling is that it requires almost no adjustment because this configuration has a self-correcting effect (cat's eye) within a certain range. This helps compensate for the inaccuracies of the ATR crystal and the flow chamber. At least one fourth sealing element, arranged on the outer side of the module body facing the flow chamber, ensures that no gas or liquid enters the optical path. This improves long-term stability because water vapor, especially infrared-active vapor, is present. Preferably, the at least one fourth sealing element comprises or is composed of at least one polymer selected from the group consisting of ethylene-propylene-diene rubber, silicone, and mixtures thereof.

[0116] Furthermore, the present invention also relates to a spectrometer, comprising at least one light source, at least one photodetector, and an optical module according to the invention. Preferably, the spectrometer is an FTIR spectrometer and / or a QCL-based infrared spectrometer.

[0117] The present invention also relates to a flow chamber for optical measurement (or for use in optical measurement), comprising a substrate having at least one inlet (for the analyte) and at least one outlet (for the analyte), and an aperture disposed (or fastened) on a first outer side of the substrate, wherein a recess is provided on the first outer side of the substrate, the recess containing a flow chamber measuring cavity connected to at least one inlet and at least one outlet (fluid).

[0118] The flow chamber further includes a device sandwiched between the aperture and at least one first wall region (facing the aperture) of the recess. This device includes an ATR crystal and at least one first sealing element for sealing the flow chamber measurement cavity, wherein the at least one first sealing element is arranged on the side of the ATR crystal facing away from the aperture.

[0119] The flow chamber includes at least one filter element arranged in a recess between the ATR crystal and at least one opening connected to at least one inlet and / or between the ATR crystal and at least one opening connected to at least one outlet.

[0120] As described below, the objective of this invention can also be achieved through this flow chamber.

[0121] The analyte guided through the flow chamber may contain large molecules (such as proteins), cellular residues, and microorganisms. These substances may deposit on the ATR crystal, leading to biocontamination. Deposits or biocontamination can further degrade measurements because the deposited components contribute an excessively large signal in the measurement or measurement spectrum, thus affecting measurement quality. Furthermore, deposits on the ATR crystal can contaminate the analyte at that location in subsequent measurements.

[0122] By arranging at least one filter element in the recess between the ATR crystal and at least one opening connected to at least one inlet, larger molecules (e.g., proteins), cellular residues, and microorganisms contained in the analyte can now be kept away from the ATR crystal, as these components are trapped by the filter element, while the liquid containing the relevant smaller molecules for optical measurement passes through the filter element. Therefore, deposits or biocontamination on the ATR crystal can be better avoided. Thus, contamination of the flow chamber measurement cavity and (in the future) the analyte within it can be better prevented by the filter element.

[0123] In addition, the filter element can also keep air bubbles in the analyte away from the ATR crystal. These air bubbles, when attached to the ATR crystal, can also have an undesirable effect on the measurement or the measurement spectrum.

[0124] Preferably, the matrix is ​​composed of at least one material having a first coefficient of thermal expansion, and the pore size is composed of at least one material having a second coefficient of thermal expansion different from the first coefficient of thermal expansion.

[0125] The present invention also relates to the following aspects A1 to A15:

[0126] Aspect A1 :

[0127] A flow chamber (100) for optical measurement includes a substrate (1) having at least one inlet (2) and at least one outlet (3) and an aperture (4) disposed on a first outer side of the substrate (1), wherein a recess (5) is provided on the first outer side of the substrate (1), the recess containing a flow chamber measurement cavity connected to at least one inlet (2) and at least one outlet (3), wherein the substrate (1) is composed of at least one material having a first coefficient of thermal expansion, and the aperture (4) is composed of at least one material having a second coefficient of thermal expansion different from the first coefficient of thermal expansion.

[0128] The flow chamber (100) further includes a device sandwiched between at least one first wall region of the aperture (4) and the recess (5), the device including an ATR crystal (7) and at least one first sealing element (8) for sealing the flow chamber measurement cavity, wherein the at least one first sealing element (8) is arranged on the side of the ATR crystal (7) opposite to the aperture (4).

[0129] The aperture (4) can be fixed at least at a first fixing point on the base (1) by at least one first fixing member (9), such that the base (1) and the aperture (4) at the at least one first fixing point are substantially immobile relative to each other in the x-direction parallel to the first outer side of the base (1), the y-direction parallel to the first outer side of the base (1), and the z-direction perpendicular to the first outer side of the base (1).

[0130] The aperture can be fixed at at least one second fixed position on the substrate (1) by at least one second fixing member (10), such that the substrate (1) and the aperture (4) can not move relative to each other in the z direction at at least one second fixed position, and can only move relative to each other to a certain extent in the x and y directions respectively, so that the different expansion and / or contraction of the components of the flow chamber (100) that occur when the temperature changes can be compensated.

[0131] Aspect A2:

[0132] According to the flow chamber (100) of the foregoing aspect, the aperture (4) is characterized in that it can be fixed at the substrate (1) at at least one second fixing point by at least one second fixing member (10), such that the substrate (1) and the aperture (4) at the at least one second fixing point are substantially immobile relative to each other in the z direction, and can be movable relative to each other in the x direction and y direction by at least 0.01 mm, preferably at least 0.05 mm, particularly preferably at least 0.1 mm, and / or at most 1 mm, preferably at most 0.8 mm, particularly preferably at most 0.5 mm.

[0133] Aspect A3:

[0134] According to one of the aforementioned aspects, the flow chamber (100) is characterized in that,

[0135] - At least one first fastener (9) is selected from: the group consisting of countersunk screws and combinations thereof, wherein at least one first fastener (9) is preferably at least one countersunk screw, and / or

[0136] - At least one second fastener (10) is selected from the group consisting of a semi-circular head screw, a rivet, a cylindrical head screw and combinations thereof, wherein at least one first fastener (10) is preferably at least one semi-circular head screw.

[0137] Aspect A4:

[0138] According to one of the aforementioned aspects, the flow chamber (100) is characterized in that,

[0139] - At least one material constituting the matrix (1) is at least one polymer, preferably selected from: the group consisting of polyetheretherketone, polytetrafluoroethylene, polypropylene, polysulfone, polyethersulfone, polycarbonate, polyvinyl chloride, polylactic acid, polyamide, thermoplastic polyurethane, acrylonitrile-butadiene-styrene, UV-curable synthetic resins and mixtures thereof, and / or

[0140] - At least one material comprising the aperture (4) is selected from the group consisting of metals, such as iron; alloys, preferably iron-containing alloys, such as stainless steel; polymers, such as polyetheretherketone; and mixtures and combinations thereof, wherein the aperture (4) preferably comprises stainless steel or is composed of thereto.

[0141] Aspect A5:

[0142] The flow chamber (100) according to one of the aforementioned aspects is characterized by an ATR crystal (7).

[0143] - Contains or is composed of at least one material that is at least partially transparent to light with wavelengths of 2µm to 20µm, preferably 4µm to 12µm, wherein the ATR crystal (7) preferably contains or is composed of at least one material selected from the group consisting of silicon, diamond, germanium, zinc selenide, zinc sulfide, and mixtures and combinations thereof, wherein the ATR crystal particularly preferably contains or is composed of silicon, and / or

[0144] - Includes multiple microprisms, and / or

[0145] - A structured portion (7a) is provided on the side facing the aperture, preferably a structured portion (7a) with a groove or recess.

[0146] Aspect A6:

[0147] According to one of the aforementioned aspects, the flow chamber (100) is characterized in that,

[0148] - At least one first sealing element (8)

[0149] • Contains or consists of at least one polymer selected from: the group consisting of ethylene-propylene-diene rubber, silicone, and mixtures thereof, and / or

[0150] • Constructed in the form of a circular ring, and / or

[0151] • It is in sealed contact with at least one first wall region (5) of the ATR crystal (7) and / or the recess.

[0152] and / or

[0153] - The flow chamber (100) includes at least one second sealing element (11) arranged around the recess (5), wherein the at least one second sealing element (11) preferably

[0154] • Contains or consists of at least one polymer selected from: the group consisting of ethylene-propylene-diene rubber, silicone, and mixtures thereof, and / or

[0155] • Constructed in the form of a circular ring, and / or

[0156] • At least partially arranged in an additional recess, which is arranged around the recess (5) and located on the first outer side of the base (1), and / or

[0157] • It is in sealing contact with the substrate (1) and / or the aperture (4).

[0158] Aspect A7:

[0159] According to one of the foregoing aspects, the flow chamber (100) is characterized in that it includes at least one filter element (15) arranged in a recess (5) between the ATR crystal (7) and at least one opening connected to at least one inlet (2) and / or between the ATR crystal (7) and at least one opening connected to at least one outlet (3), wherein preferably

[0160] - At least one filter element is selected from: (the group consisting of cellulose filter elements, such as cellulose filter elements made from regenerated cellulose; paper filter elements; glass fiber filter elements; cellulose acetate filter elements; polyethersulfone filter elements; nylon filter elements; polyvinylidene fluoride filter elements; polytetrafluoroethylene filter elements; polypropylene filter elements; polycarbonate filter elements; and combinations thereof, wherein at least one filter element is preferably selected from:) the group consisting of cellulose filter elements, paper filter elements, glass fiber filter elements, and combinations thereof, and / or

[0161] - It has a thickness of 0.001mm to 5mm, preferably 0.01mm to 1mm, and particularly preferably 0.02mm to 0.2mm.

[0162] Aspect A8:

[0163] According to aspect A7, the flow chamber (100) is characterized in that the flow chamber (100) further includes at least one filter holder (16) for holding at least one filter element (15), the at least one filter holder being arranged between the ATR crystal (7) and the at least one filter element (15), wherein the at least one filter holder (16) preferably has a grid structure and a frame extending around the grid structure, wherein

[0164] - The frame is in contact with the ATR crystal (7), and the grid structure is not in contact with the ATR crystal (7), wherein the grid structure is preferably arranged at a distance of 0.001 mm to 5 mm, preferably 0.005 mm to 2 mm, particularly preferably 0.008 mm to 1 mm, and extremely preferably 0.01 mm to 0.1 mm from the ATR crystal (7), and / or

[0165] - At least one filter element (15) is held between the frame and at least one second wall region of the recess (5) facing the aperture (4), and / or

[0166] - The central wall region of the recess (5) facing the aperture (4) has at least one retaining element, preferably at least two retaining elements, wherein at least one filter element (15) is held between the grid structure and at least one retaining element.

[0167] Aspect A9:

[0168] According to aspect A7, the flow chamber (100) is characterized in that at least one filter element (15) is arranged to be in direct contact with at least one photoresist coating (16) applied to the ATR crystal (7), wherein preferably...

[0169] - At least one photoresist coating (16) has a thickness of 0.1µm to 100µm, preferably 1µm to 50µm, particularly preferably 5µm to 20µm, and / or

[0170] - At least one photoresist coating (16) is applied to the ATR crystal (7) in the form of a grid or strip, wherein the arrangement of the photoresist coating (16) on the ATR crystal (7) preferably adapts to the structured portion of the ATR crystal (7), which has the structured portion on the side facing the aperture (4), and / or

[0171] - At least one filter element (15) is fastened to at least one first sealing element (8), preferably connected to at least one first sealing element (8) in a material-fit manner.

[0172] Aspect A10:

[0173] According to one of the aforementioned aspects, the flow chamber (100) is characterized by the recess (5).

[0174] - Arranged between at least one first fixing part and at least one second fixing part, wherein the at least one first fixing part and at least one second fixing part preferably have the same distance from the recess (5), and / or

[0175] - The central wall region of the recess (5) facing the aperture (4) has a structured portion, preferably a serrated structured portion, and / or

[0176] - The central wall region of the recess (5) facing the aperture (4) has at least one opening connected to at least one inlet (2), and / or

[0177] - The central wall region of the recess (5) facing the aperture (4) has at least one opening connected to at least one outlet (3).

[0178] Aspect A11 :

[0179] According to one of the aforementioned aspects, the flow chamber (100) is characterized in that it includes at least one third fastener (12), preferably a separate third fastener (12), for fastening the flow chamber (100) to the module body of the optical module, wherein

[0180] - At least one third fastener (12) has a main extending direction, wherein the angle between the main extending direction and the first outer side of the base (1) is 20° to 85°, preferably 30° to 70°, particularly preferably 40° to 65°, and / or

[0181] - At least one third fastener (12) is selected from the group consisting of head screws, round head screws and combinations thereof, wherein at least one third fastener (12) is preferably at least one head screw, particularly preferably a single head screw, and / or

[0182] - The aperture (4) has a protruding area (13) that protrudes beyond the second outer side of the base (1), wherein the recess (5) is preferably arranged between the second outer side of the base (1) and at least one third fastener (12), and / or

[0183] - The flow chamber (100) also has at least one third sealing element (14) arranged around at least one third fastener (12) and sealed to at least one third fastener (12).

[0184] Aspect A12:

[0185] An optical module (1000) includes a module body (200) and a flow chamber (100) according to one of the foregoing aspects, the flow chamber being fastened to the module body.

[0186] Aspect A13:

[0187] According to aspect A12, the optical module (1000) is characterized in that the flow chamber (100) is fastened to the module body (200) by at least one third fastener (12), preferably a separate third fastener (12), and a stop element (23) arranged on the outer side of the module body (200) facing the flow chamber (100), wherein the stop element (23) has a stop surface, the flow chamber (100) is pressed against the stop surface by at least one third fastener (12), and wherein preferably

[0188] - The angle between the stop surface and the first outer side of the base (1) is 20° to 85°, preferably 30° to 65°, particularly preferably 40° to 50°, and / or

[0189] - At least one third fastener (12) has a main extending direction, wherein the angle between the main extending direction and the first outer side of the base (1) is 20° to 85°, preferably 30° to 70°, particularly preferably 40° to 65°, and / or

[0190] - At least one third fastener (12) is selected from the group consisting of head screws, round head screws and combinations thereof, wherein at least one third fastener (12) is preferably at least one head screw, particularly preferably a single head screw, and / or

[0191] - The aperture (4) has a protruding area (13) that protrudes beyond the second outer side of the base (1), wherein the protruding area (13) presses against the stop surface, and wherein the recess (5) is preferably arranged between the second outer side of the base (1) and at least one third fastener (12), and / or

[0192] - The flow chamber (100) also has at least one third sealing element (14) arranged around at least one third fastener (12).

[0193] Aspect A14:

[0194] According to aspect A12 or A13, the optical module (1000) is characterized in that the module body (200)

[0195] - Includes a lens (17) for coupling an input light beam incident on the ATR crystal (7) and for coupling an output light beam reflected from the ATR crystal (7), wherein the lens (17) preferably comprises or is composed of zinc selenide, and / or

[0196] - Includes an optical window (18) disposed between the ATR crystal (7) and the lens (17), wherein the optical window (18) preferably comprises or is composed of zinc sulfide, and / or

[0197] - Includes at least one fourth sealing element (19) arranged on the outer side of the module body (200) facing the flow chamber (100) and in sealing contact with the side of the flow chamber (100) facing the module body (200), wherein the at least one fourth sealing element (19) is preferably configured in the form of a circular ring, and / or

[0198] - Includes a polarizer (20) for polarizing the beam reflected from the ATR crystal (7) and subsequently coupled out.

[0199] Aspect A15:

[0200] A spectrometer includes at least one light source, at least one photodetector, and an optical module (1000) according to one of aspects A12 to A14, wherein the spectrometer is preferably an FTIR spectrometer or a QCL-based infrared spectrometer.

[0201] The present invention also relates to the following aspects B1 to B15:

[0202] Aspect B1 :

[0203] A flow chamber for optical measurement includes a substrate having at least one inlet and at least one outlet, and an aperture disposed (or fastened) on a first outer side of the substrate, wherein a recess is provided on the first outer side of the substrate, the recess containing a flow chamber measurement cavity connected to at least one inlet and at least one outlet.

[0204] The flow chamber further includes a device sandwiched between at least one first wall region of the aperture and the recess. This device includes an ATR crystal and at least one (first) sealing element for sealing the flow chamber measurement cavity, wherein the at least one (first) sealing element is arranged on the side of the ATR crystal opposite to the aperture.

[0205] The flow chamber includes at least one filter element arranged in a recess between the ATR crystal and at least one opening connected to at least one inlet and / or between the ATR crystal and at least one opening connected to at least one outlet.

[0206] Aspect B2:

[0207] According to aspect B1, the flow chamber is characterized in that,

[0208] The matrix is ​​composed of at least one material having a first coefficient of thermal expansion, and / or the pore size is composed of at least one material having a second coefficient of thermal expansion different from the first coefficient of thermal expansion.

[0209] Preferably

[0210] - The aperture can be fixed at at least one first fixing point on the substrate by at least one first fixing member, such that the substrate and the aperture at the at least one first fixing point are substantially immobile relative to each other in the x-direction extending parallel to the first outer side of the substrate, the y-direction extending parallel to the first outer side of the substrate, and the z-direction extending perpendicular to the first outer side of the substrate.

[0211] - The aperture can be fixed at at least one second fixed position on the substrate by at least one second fastener, such that the substrate and the aperture can not move relative to each other in the z direction at at least one second fixed position, and can only move relative to each other to a certain extent in the x and y directions respectively, so that the different expansion and / or contraction of the components of the flow chamber (especially the substrate and the aperture) that occur during temperature changes can be compensated (or can be compensated so that temperature changes do not cause bending of the components of the flow chamber (especially the substrate and the aperture)).

[0212] Particularly preferably, the aperture can be fixed at the base at at least one second fixing point by at least one second fixing member, such that the base and the aperture are substantially immobile relative to each other in the z direction at at least one second fixing point, and can move relative to each other in the x and y directions by at least 0.01 mm, preferably at least 0.05 mm, particularly preferably at least 0.1 mm, and / or at most 1 mm, preferably at most 0.8 mm, particularly preferably at most 0.5 mm.

[0213] Aspect B3:

[0214] According to aspect B2, the flow chamber is characterized in that,

[0215] - At least one first fastener is selected from: the group consisting of countersunk screws and combinations thereof, wherein at least one first fastener is preferably at least one countersunk screw, and / or

[0216] - At least one second fastener is selected from the group consisting of round head screws, rivets, cylindrical head screws and combinations thereof, wherein at least one first fastener is preferably at least one round head screw.

[0217] Aspect B4:

[0218] According to one of aspects B1 to B3, the flow chamber is characterized in that,

[0219] - The matrix comprises or is composed of at least one polymer, preferably selected from: the group consisting of polyetheretherketone, polytetrafluoroethylene, polypropylene, polysulfone, polyethersulfone, polycarbonate, polyvinyl chloride, polylactic acid, polyamide, thermoplastic polyurethane, acrylonitrile-butadiene-styrene, UV-curable synthetic resins and mixtures thereof, and / or

[0220] - The pore size comprises or is composed of at least one material selected from: metals, such as iron; alloys, preferably iron-containing alloys, such as stainless steel; polymers, such as polyetheretherketone; and mixtures and combinations thereof, wherein the pore size preferably comprises or is composed of stainless steel.

[0221] Aspect B5:

[0222] According to one of aspects B1 to B4, the flow chamber is characterized by an ATR crystal.

[0223] - Contains or is composed of at least one material that is optically transparent for wavelengths of 2µm to 20µm, preferably 4µm to 12µm, wherein the ATR crystal preferably contains or is composed of at least one material selected from the group consisting of silicon, diamond, germanium, zinc selenide, zinc sulfide, and mixtures and combinations thereof, wherein the ATR crystal particularly preferably contains or is composed of silicon, and / or

[0224] - Includes multiple microprisms, and / or

[0225] - A structured portion is provided on the side facing the aperture, preferably a structured portion with grooves (or recesses).

[0226] Aspect B6:

[0227] According to one of aspects B1 to B5, the flow chamber is characterized in that,

[0228] - At least one first sealing element

[0229] • Contains or consists of at least one polymer selected from: the group consisting of ethylene-propylene-diene rubber, silicone, and mixtures thereof, and / or

[0230] • Constructed in the form of a circular ring, and / or

[0231] • Sealing contact with at least one first wall region of the ATR crystal and / or recess.

[0232] and / or

[0233] - The flow chamber includes at least one second sealing element arranged around the recess, wherein the at least one second sealing element preferably

[0234] • Contains or consists of at least one polymer selected from: the group consisting of ethylene-propylene-diene rubber, silicone, and mixtures thereof, and / or

[0235] • Constructed in the form of a circular ring, and / or

[0236] • At least partially arranged in a separate recess, which is arranged around the recess and positioned on the first outer side of the substrate, and / or

[0237] • Seal contact with the substrate and / or pore size.

[0238] Aspect B7:

[0239] According to one of aspects B1 to B6, the flow chamber is characterized in that,

[0240] - At least one filter element is selected from: the group consisting of cellulose filter elements, paper filter elements, glass fiber filter elements, and combinations thereof, and / or

[0241] - It has a thickness of 0.001mm to 5mm, preferably 0.01mm to 1mm, and particularly preferably 0.02mm to 0.2mm.

[0242] Aspect B8:

[0243] According to one of aspects B1 to B7, the flow chamber is characterized in that it further includes at least one filter holder for holding at least one filter element, the at least one filter holder being arranged between the ATR crystal and the at least one filter element.

[0244] At least one of the filter retainers preferably has a grid structure and a frame extending around the grid structure, wherein

[0245] - The frame is in contact with the ATR crystal, while the grid structure is not in contact with the ATR crystal. The grid structure is preferably arranged at a distance of 0.001 mm to 5 mm, more preferably 0.005 mm to 2 mm, particularly preferably 0.008 mm to 1 mm, and extremely preferably 0.01 mm to 0.1 mm from the ATR crystal.

[0246] - At least one filter element is held between the frame and at least one second wall region of the recess facing the aperture, and / or

[0247] - The central wall region of the recess facing the aperture has at least one retaining element, preferably at least two retaining elements, wherein at least one filter element is held between the grid structure and at least one retaining element.

[0248] Aspect B9:

[0249] According to one of aspects B1 to B7, the flow chamber is characterized in that at least one filter element is arranged in direct contact with at least one photoresist coating applied to the ATR crystal, wherein preferably...

[0250] - At least one photoresist coating has a thickness of 0.1µm to 100µm, preferably 1µm to 50µm, particularly preferably 5µm to 20µm, and / or

[0251] - At least one photoresist coating is applied to the ATR crystal in the form of a grid or strip, wherein the arrangement of the photoresist coating on the ATR crystal is preferably adapted to the structured portion of the ATR crystal, which has the structured portion on the side of the ATR crystal facing the aperture, and / or

[0252] - At least one filter element is fastened to at least one first sealing element, preferably in a material-fit manner to at least one first sealing element.

[0253] Aspect B10:

[0254] According to one of aspects B1 to B9, the flow chamber is characterized by a recess...

[0255] - Arranged between at least one first fixing part and at least one second fixing part, wherein the at least one first fixing part and at least one second fixing part preferably have the same distance from the recess, and / or

[0256] - The central wall region of the recess facing the aperture has a structured portion, preferably a serrated structured portion, and / or

[0257] - The central wall region of the recess facing the aperture has at least one opening connected to at least one inlet, and / or

[0258] - The central wall region of the recess facing the aperture has at least one opening connected to at least one outlet.

[0259] Aspect B11 :

[0260] According to one of aspects B1 to B10, the flow chamber is characterized in that it includes at least one third fixing member, preferably a separate third fixing member, for fastening the flow chamber to the module body of the optical module, wherein...

[0261] - At least one third fastener has a main extending direction, wherein the angle between the main extending direction and the first outer side of the base is 20° to 85°, preferably 30° to 70°, particularly preferably 40° to 65°, and / or

[0262] - At least one third fastener is selected from the group consisting of headstock screws, roundhead screws, and combinations thereof, wherein the at least one third fastener is preferably at least one headstock screw, particularly preferably a single headstock screw, and / or

[0263] - The aperture has a protruding area that extends beyond the second outer side of the substrate (adjacent to the first outer side of the substrate), wherein the recess is preferably arranged between the second outer side of the substrate and at least one third fastener (and / or

[0264] - The flow chamber also has at least one third sealing element, which is arranged around at least one third fastener and is sealed to at least one third fastener.

[0265] Aspect B12:

[0266] An optical module includes a module body and a flow chamber according to one of aspects B1 to B11, the flow chamber being fastened to the module body.

[0267] Aspect B13:

[0268] According to the optical module of aspect B12, the flow chamber is characterized in that it is fastened to the module body by at least one third fastener, preferably a separate third fastener, and a stop element arranged on the outer side of the module body facing the flow chamber, wherein the stop element has a stop surface, the flow chamber is pressed against the stop surface by at least one third fastener, and wherein preferably...

[0269] - The angle between the stop surface and the first outer side of the substrate is 20° to 85°, preferably 30° to 65°, particularly preferably 40° to 50°, and / or

[0270] - At least one third fastener has a main extending direction, wherein the angle between the main extending direction and the first outer side of the base is 20° to 85°, preferably 30° to 70°, particularly preferably 40° to 65°, and / or

[0271] - At least one third fastener is selected from the group consisting of head screws, round head screws, and combinations thereof, wherein the at least one third fastener is preferably at least one head screw, particularly preferably a single head screw, and / or

[0272] - The aperture has a protruding region that extends beyond the second outer side of the substrate (adjacent to the first outer side of the substrate), wherein the protruding region presses against the stop surface, and wherein the recess is preferably arranged between the second outer side of the substrate and at least one third fastener (and / or

[0273] - The flow chamber also has at least one third sealing element, which is arranged around at least one third fastener.

[0274] Aspect B14:

[0275] According to the optical module of aspect B12 or B13, the module body is characterized by...

[0276] - Includes lenses for coupling an input light beam incident on the ATR crystal and for coupling an output light beam reflected from the ATR crystal, wherein the lenses preferably contain or are composed of zinc selenide, and / or

[0277] - Includes an optical window disposed between the ATR crystal and the lens, wherein the optical window preferably comprises or is composed of zinc sulfide, and / or

[0278] - Includes at least one fourth sealing element, which is arranged on the outer side of the module body facing the flow chamber and makes sealing contact with the side of the flow chamber facing the module body, wherein the at least one fourth sealing element is configured in the form of a circular ring, and / or

[0279] - Includes a polarizer for polarizing the beam reflected from the ATR crystal and subsequently coupled out.

[0280] Aspect B15:

[0281] A spectrometer includes at least one light source, at least one photodetector, and an optical module according to one of aspects B12 to B14, wherein the spectrometer is preferably an FTIR spectrometer or a QCL-based infrared spectrometer.

[0282] The present invention will be described in more detail with reference to the following drawings and examples, but the invention is not limited to the parameters specifically shown.

[0283] Example 1

[0284] exist Figures la to lc The first exemplary embodiment of the flow chamber according to the present invention is shown in multiple views. Figure la A top view of the flow chamber 100 is shown. Figure lb A side sectional view of the flow chamber 100 is shown, wherein the section runs along... Figure la The line AA shown is used. Furthermore... Figure lc An exploded view of the flow chamber is shown.

[0285] The flow chamber 100 includes a polymer matrix 1 (e.g., made of "BioMed Clear" by formlabs), which has an inlet 2 for the analyte and an outlet 3 for the analyte, and an aperture 4 disposed on a first outer side of the matrix 1, the aperture 4 being made of an alloy, such as stainless steel. Thus, the matrix 1 and the aperture 4 are composed of different materials with different coefficients of thermal expansion.

[0286] A recess 5 is provided on the first outer side of the substrate 1, the recess containing a flow chamber measuring cavity that is fluidly connected to the inlet 2 and the outlet 3. An aperture 4 is arranged on the first outer side of the substrate 1, and the recess 5 containing the flow chamber measuring cavity is also provided on this first outer side. Therefore, the recess 5 with the flow chamber measuring cavity is adjacent to the aperture 4. In the region of the aperture 4, an aperture ring 6 is also configured such that the aperture ring 6 is adjacent to the recess 5.

[0287] Figure Id It shows Figure lbThe enlarged portion shows an enlarged side view of the recess 5 and the elements arranged within it. The flow chamber 100 also includes a device consisting of an ATR crystal 7 and a first sealing element 8 for sealing the flow chamber measurement cavity, the device being sandwiched between the aperture 4 and a first wall region of the recess 5 facing the aperture 4. Here, the first sealing element 8 is arranged on the side of the ATR crystal 7 facing away from the aperture 4 and makes sealing contact with the ATR crystal 7 and the first wall region of the recess 5. The central wall region of the recess facing the aperture 4 has an opening connected to the inlet 2 and an opening connected to the outlet 3.

[0288] The ATR crystal 7 (e.g., composed of silicon) includes multiple microprisms and has a structured portion 7a with V-grooves or recesses on the side facing the aperture. The first sealing element 8 is composed of a polymer material (e.g., ethylene-propylene-diene rubber or silicone) and is configured in the form of a circular ring (O-ring).

[0289] The flow chamber is now configured such that it is defined by the ATR crystal 7, the sealing element 8, and the wall region of the recess 5. By fixing the aperture 4 to the substrate 1, the device including the ATR crystal 7 and the sealing element 8 can be clamped between the aperture 4 and the first wall region of the recess 5, thereby achieving a seal in the flow chamber.

[0290] Here, the aperture 4 can be fixed at the first fixing position on the base 1 by the first fixing member 9, and at the second fixing position by the second fixing member 10. Here, the recess 5 is arranged between the first fixing position (or the first fixing member 9) and the second fixing position (or the second fixing member 10), wherein the first fixing position (or the first fixing member 9) and the second fixing position (or the second fixing member 10) are equidistant from the recess 5. The first fixing member 9 is a countersunk screw, and the second fixing member 10 is a semi-circular head screw. With the countersunk screw, the aperture 4 can be fixed at the first fixing position on the base 1, such that the base 1 and the aperture 4 at the first fixing position are substantially immobile relative to each other in the x-direction parallel to the first outer side of the base 1, the y-direction parallel to the first outer side of the base 1, and the z-direction perpendicular to the first outer side of the base 1. With the use of a semi-circular head screw, the aperture 4 can be fixed at the second fixed position at the base 1, so that the base 1 and the aperture 4 at the second fixed position can not move relative to each other in the z direction, and can only move relative to each other to a limited extent in the x and y directions, so that the different expansion and contraction of the components of the flow chamber that occur during temperature changes can be compensated.

[0291] Therefore, during drastic temperature changes (e.g., during sterilization or autoclaving of the flow chamber), although the substrate 1 and the pore size 4 expand differently (due to their different coefficients of thermal expansion), this expansion (due to a certain degree of mobility in the x and y directions) does not cause bending of the components, thus preventing loosening of the clamped device, including the ATR crystal 7 and the first sealing element 8. In this way, unsealed areas are prevented in the device where the flow chamber measurement cavity is no longer adequately sealed. Therefore, even during drastic temperature changes (e.g., during sterilization or autoclaving of the flow chamber), the flow chamber maintains a high degree of sealing, preventing contaminants from entering the flow chamber cavity from the outside through unsealed areas. Thus, contamination of the flow chamber cavity and the substance measured therein by external contaminants or microorganisms can be better avoided.

[0292] The flow chamber 100 also includes a second sealing element 11 arranged around the recess 5, wherein the second sealing element is composed of a polymer material (e.g., ethylene-propylene-diene rubber or silicone) and is configured in the form of a circular ring (O-ring).

[0293] Furthermore, the flow chamber 100 includes a separate third fastener 12 for securing the flow chamber to the module body of the optical module. The third fastener 12 is a head screw. This head screw is arranged such that the angle between the main extension direction of the head screw (or the third fastener 12) and the first outer side of the substrate 1 is 40° to 65°. Additionally, the aperture 4 has a protruding region 13 that protrudes beyond the second outer side of the substrate 1 adjacent to the first outer side of the substrate 1. Here, a recess 5 is arranged between the second outer side of the substrate 1 and the third fastener 12. Furthermore, the aperture also has a third sealing element 14 that is arranged around at least one third fastener and is sealingly connected to the third fastener 12.

[0294] Example 2

[0295] exist Figures 2a to 2c A second exemplary embodiment of the flow chamber according to the present invention is shown in multiple views. Figure 2a A top view of the flow chamber 100 is shown. Figure 2b A side sectional view of the flow chamber 100 is shown, wherein the section runs along... Figure 2a The line AA shown is used. Furthermore... Figure 2c An exploded view of the flow chamber is shown.

[0296] The flow chamber 100 includes a polymer matrix 1 (e.g., made of "BioMed Clear" by formlabs), which has an inlet 2 for the analyte and an outlet 3 for the analyte, and an aperture 4 disposed on a first outer side of the matrix 1, the aperture 4 being made of an alloy, such as stainless steel. Thus, the matrix 1 and the aperture 4 are composed of different materials with different coefficients of thermal expansion.

[0297] A recess 5 is provided on the first outer side of the substrate 1, the recess containing a flow chamber measuring cavity that is fluidly connected to the inlet 2 and the outlet 3. An aperture 4 is arranged on the first outer side of the substrate 1, and the recess 5 containing the flow chamber measuring cavity is also provided on this first outer side. Therefore, the recess 5 with the flow chamber measuring cavity is adjacent to the aperture 4. In the region of the aperture 4, an aperture ring 6 is also configured such that the aperture ring 6 is adjacent to the recess 5.

[0298] Figure 2d It shows Figure 2b The enlarged portion shows an enlarged side view of the recess 5 and the elements arranged within it. The flow chamber 100 also includes a device consisting of an ATR crystal 7 and a first sealing element 8 for sealing the flow chamber measurement cavity, the device being sandwiched between the aperture 4 and a first wall region of the recess 5 facing the aperture 4. Here, the first sealing element 8 is arranged on the side of the ATR crystal 7 facing away from the aperture 4 and makes sealing contact with the ATR crystal 7 and the first wall region of the recess 5. The central wall region of the recess facing the aperture 4 has an opening connected to the inlet 2 and an opening connected to the outlet 3.

[0299] The ATR crystal 7 (e.g., composed of silicon) includes multiple microprisms and has a structured portion 7a with V-grooves or recesses on the side facing the aperture. The first sealing element 8 is composed of a polymer material (e.g., ethylene-propylene-diene rubber or silicone) and is configured in the form of a circular ring (O-ring).

[0300] The flow chamber is now configured such that it is defined by the ATR crystal 7, the sealing element 8, and the wall region of the recess 5. By fixing the aperture 4 to the substrate 1, the device including the ATR crystal 7 and the sealing element 8 can be clamped between the aperture 4 and the first wall region of the recess 5, thereby achieving a seal in the flow chamber.

[0301] Here, the aperture 4 can be fixed at the first fixing position on the base 1 by the first fixing member 9, and at the second fixing position by the second fixing member 10. Here, the recess 5 is arranged between the first fixing position (or the first fixing member 9) and the second fixing position (or the second fixing member 10), wherein the first fixing position (or the first fixing member 9) and the second fixing position (or the second fixing member 10) are equidistant from the recess 5. The first fixing member 9 is a countersunk screw, and the second fixing member 10 is a semi-circular head screw. With the countersunk screw, the aperture 4 can be fixed at the first fixing position on the base 1, such that the base 1 and the aperture 4 at the first fixing position are substantially immobile relative to each other in the x-direction parallel to the first outer side of the base 1, the y-direction parallel to the first outer side of the base 1, and the z-direction perpendicular to the first outer side of the base 1. With the use of a semi-circular head screw, the aperture 4 can be fixed at the second fixed position at the base 1, so that the base 1 and the aperture 4 at the second fixed position can not move relative to each other in the z direction, and can only move relative to each other to a limited extent in the x and y directions, so that the different expansion and contraction of the components of the flow chamber that occur during temperature changes can be compensated.

[0302] Therefore, during drastic temperature changes (e.g., during sterilization or autoclaving of the flow chamber), although the substrate 1 and the pore size 4 expand differently (due to their different coefficients of thermal expansion), this expansion (due to a certain degree of mobility in the x and y directions) does not cause bending of the components, thus preventing loosening of the clamped device, including the ATR crystal 7 and the first sealing element 8. In this way, unsealed areas are prevented in the device where the flow chamber measurement cavity is no longer adequately sealed. Therefore, even during drastic temperature changes (e.g., during sterilization or autoclaving of the flow chamber), the flow chamber maintains a high degree of sealing, preventing contaminants from entering the flow chamber cavity from the outside through unsealed areas. Thus, contamination of the flow chamber cavity and the substance measured therein by external contaminants or microorganisms can be better avoided.

[0303] The flow chamber 100 also includes a second sealing element 11 arranged around the recess 5, wherein the second sealing element is composed of a polymer material (e.g., ethylene-propylene-diene rubber or silicone) and is configured in the form of a circular ring (O-ring).

[0304] Furthermore, the flow chamber 100 includes a separate third fastener 12 for securing the flow chamber to the module body of the optical module. The third fastener 12 is a head screw. This head screw is arranged such that the angle between the main extension direction of the head screw (or the third fastener 12) and the first outer side of the substrate 1 is 40° to 65°. Additionally, the aperture 4 has a protruding region 13 that protrudes beyond the second outer side of the substrate 1 adjacent to the first outer side of the substrate 1. Here, a recess 5 is arranged between the second outer side of the substrate 1 and the third fastener 12. Furthermore, the aperture also has a third sealing element 14 that is arranged around at least one third fastener and is sealingly connected to the third fastener 12.

[0305] Furthermore, the flow chamber 100 also includes a filter element 15 disposed in the recess 5 between the ATR crystal 7 and the opening connected to the inlet 2, and between the ATR crystal 7 and the opening connected to the outlet 3. The filter element 15 may be, for example, a cellulose filter element having a thickness of 0.02 mm to 0.2 mm.

[0306] The analyte guided through the flow chamber may contain large molecules (such as proteins), cellular residues, and microorganisms. These substances may deposit on the ATR crystal, leading to biocontamination. Deposits or biocontamination can further degrade measurements because the deposited components contribute an excessively large signal in the measurement or measurement spectrum, thus affecting measurement quality. Furthermore, deposits on the ATR crystal can contaminate the analyte at that location in subsequent measurements.

[0307] The filter element 15 keeps larger molecules (e.g., proteins), cellular residues, and microorganisms in the analyte away from the ATR crystal 8, as these components are trapped by the filter element 15, while smaller molecules relevant to optical measurements pass through. Therefore, deposits or biocontamination on the ATR crystal 7 are better avoided. Thus, the filter element 15 also better prevents contamination of the flow chamber and the analyte within it. Furthermore, the filter element 15 keeps air bubbles present in the analyte away from the ATR crystal 7, as these bubbles, when attached to the ATR crystal 7, can also have undesirable effects on the measurement or the measured spectrum.

[0308] Furthermore, the flow chamber 100 also includes a filter holder 16 for holding the filter element 15, which is arranged between the ATR crystal 7 and the filter element 15. The filter holder 16 has a grid structure and a frame extending around the grid structure. Preferably, the frame contacts the ATR crystal 7, while the grid structure does not contact the ATR crystal 7. For example, the grid structure can be arranged at a distance of 0.01 mm to 1 mm from the ATR crystal 7. The filter element 15 can preferably be held between the frame and the second wall region of the recess 5 facing the aperture 4. Preferably, the central wall region of the recess 5 facing the aperture 4 can have three holding elements, wherein the filter element 15 can be held between the grid structure and the holding elements. In addition, the central wall region of the recess 5 can have a serrated structured portion, which can reduce the risk of biocontamination on the filter element 15.

[0309] Example 3

[0310] exist Figures 3a to 3c A third exemplary embodiment of the flow chamber according to the present invention is shown in multiple views. Figure 3a A top view of the flow chamber 100 is shown. Figure 3b A side sectional view of the flow chamber 100 is shown, wherein the section runs along... Figure 3a The line AA shown is used. Furthermore... Figure 3c An exploded view of the flow chamber is shown.

[0311] The flow chamber 100 includes a polymer matrix 1 (e.g., made of "BioMed Clear" by formlabs), which has an inlet 2 for the analyte and an outlet 3 for the analyte, and an aperture 4 disposed on a first outer side of the matrix 1, the aperture 4 being made of an alloy, such as stainless steel. Thus, the matrix 1 and the aperture 4 are composed of different materials with different coefficients of thermal expansion.

[0312] A recess 5 is provided on the first outer side of the substrate 1, the recess containing a flow chamber measuring cavity that is fluidly connected to the inlet 2 and the outlet 3. An aperture 4 is arranged on the first outer side of the substrate 1, and the recess 5 containing the flow chamber measuring cavity is also provided on this first outer side. Therefore, the recess 5 with the flow chamber measuring cavity is adjacent to the aperture 4. In the region of the aperture 4, an aperture ring 6 is also configured such that the aperture ring 6 is adjacent to the recess 5.

[0313] Figure 3d It shows Figure 3bThe enlarged portion shows an enlarged side view of the recess 5 and the elements arranged within it. The flow chamber 100 also includes a device consisting of an ATR crystal 7 and a first sealing element 8 for sealing the flow chamber measurement cavity, the device being sandwiched between the aperture 4 and a first wall region of the recess 5 facing the aperture 4. Here, the first sealing element 8 is arranged on the side of the ATR crystal 7 facing away from the aperture 4 and makes sealing contact with the ATR crystal 7 and the first wall region of the recess 5. The central wall region of the recess facing the aperture 4 has an opening connected to the inlet 2 and an opening connected to the outlet 3.

[0314] The ATR crystal 7 (e.g., composed of silicon) includes multiple microprisms and has a structured portion 7a with V-grooves or recesses on the side facing the aperture. The first sealing element 8 is composed of a polymer material (e.g., ethylene-propylene-diene rubber or silicone) and is configured in the form of a circular ring (O-ring).

[0315] The flow chamber is now configured such that it is defined by the ATR crystal 7, the sealing element 8, and the wall region of the recess 5. By fixing the aperture 4 to the substrate 1, the device including the ATR crystal 7 and the sealing element 8 can be clamped between the aperture 4 and the first wall region of the recess 5, thereby achieving a seal in the flow chamber.

[0316] Here, the aperture 4 can be fixed at the first fixing position on the base 1 by the first fixing member 9, and at the second fixing position by the second fixing member 10. Here, the recess 5 is arranged between the first fixing position (or the first fixing member 9) and the second fixing position (or the second fixing member 10), wherein the first fixing position (or the first fixing member 9) and the second fixing position (or the second fixing member 10) are equidistant from the recess 5. The first fixing member 9 is a countersunk screw, and the second fixing member 10 is a semi-circular head screw. With the countersunk screw, the aperture 4 can be fixed at the first fixing position on the base 1, such that the base 1 and the aperture 4 at the first fixing position are substantially immobile relative to each other in the x-direction parallel to the first outer side of the base 1, the y-direction parallel to the first outer side of the base 1, and the z-direction perpendicular to the first outer side of the base 1. With the use of a semi-circular head screw, the aperture 4 can be fixed at the second fixed position at the base 1, so that the base 1 and the aperture 4 at the second fixed position can not move relative to each other in the z direction, and can only move relative to each other to a limited extent in the x and y directions, so that the different expansion and contraction of the components of the flow chamber that occur during temperature changes can be compensated.

[0317] Therefore, during drastic temperature changes (e.g., during sterilization or autoclaving of the flow chamber), although the substrate 1 and the pore size 4 expand differently (due to their different coefficients of thermal expansion), this expansion (due to certain movement in the x and y directions) does not cause bending of the components, and thus prevents loosening of the clamped device, including the ATR crystal 7 and the first sealing element 8. In this way, unsealed areas are prevented in the device where the flow chamber measuring cavity is no longer adequately sealed. Therefore, even during drastic temperature changes (e.g., during sterilization or autoclaving of the flow chamber), the flow chamber maintains a high level of sealing, preventing contaminants from entering the flow chamber cavity from the outside through unsealed areas. Thus, contamination of the flow chamber cavity and the substance measured within it by external contaminants or microorganisms can be better avoided.

[0318] The flow chamber 100 also includes a second sealing element 11 arranged around the recess 5, wherein the second sealing element is made of a polymer material (e.g., ethylene-propylene-diene rubber or silicone) and configured in the form of a circular ring (O-ring).

[0319] Furthermore, the flow chamber 100 includes a separate third fastener 12 for securing the flow chamber to the module body of the optical module. The third fastener 12 is a head screw. This head screw is arranged such that the angle between the main extension direction of the head screw (or the third fastener 12) and the first outer side of the substrate 1 is 40° to 65°. Additionally, the aperture 4 has a protruding region 13 that protrudes beyond the second outer side of the substrate 1 adjacent to the first outer side of the substrate 1. Here, a recess 5 is arranged between the second outer side of the substrate 1 and the third fastener 12. Furthermore, the aperture also has a third sealing element 14 that is arranged around at least one third fastener and is sealingly connected to the third fastener 12.

[0320] Furthermore, the flow chamber 100 also includes a filter element 15, which is arranged in the recess 5 between the ATR crystal 7 and the opening connected to the inlet 2, and between the ATR crystal 7 and the opening connected to the outlet 3. The filter element 15 is fastened to the first sealing element 8. Here, the filter element is connected to the inner edge of the annular first sealing element 8 in a material-fitting manner, such that the entire area between the inner edges of the annular first sealing element 8 is closed by the filter element 15. Therefore, the first sealing element 8 is arranged around the filter element 15 or extends at the edge of the filter element 15. The first sealing element 8 and the filter element 15 can also be regarded here as a common seal-filter element. The filter element 15 can be, for example, a cellulose filter element having a thickness of 0.02 mm to 0.2 mm.

[0321] The filter element 15 is arranged to be in direct contact with at least one photoresist coating 16 applied to the ATR crystal. The photoresist coating 16 is applied to the ATR crystal in the form of a strip, wherein the arrangement of the photoresist coating on the ATR crystal adapts to the structured portion 7a of the ATR crystal, which is located on the aperture-facing side of the ATR crystal. The photoresist coating may have a thickness, for example, from 0.1 µm to 100 µm.

[0322] The analyte guided through the flow chamber may contain large molecules (such as proteins), cellular residues, and microorganisms. These substances may deposit on the ATR crystal, leading to biocontamination. Deposits or biocontamination can further degrade measurements because the deposited components contribute an excessively large signal in the measurement or measurement spectrum, thus affecting measurement quality. Furthermore, deposits on the ATR crystal can contaminate the analyte at that location in subsequent measurements.

[0323] The filter element 15 keeps larger molecules (e.g., proteins), cellular residues, and microorganisms in the analyte away from the ATR crystal 8, as these components are trapped by the filter element 15, while smaller molecules relevant to optical measurements pass through. Therefore, deposits or biocontamination on the ATR crystal 7 are better avoided. Thus, the filter element 15 also better prevents contamination of the flow chamber and the analyte within it. Furthermore, the filter element 15 keeps air bubbles present in the analyte away from the ATR crystal 7, as these bubbles, when attached to the ATR crystal 7, can also have undesirable effects on the measurement or the measured spectrum.

[0324] Example 4

[0325] Figure 4 A cross-sectional view of an exemplary embodiment of a spectrometer according to the present invention is shown. The spectrometer includes an exemplary embodiment of an optical module 1000 according to the present invention (in... Figure 4 (Indicated by a dashed box in the image), the optical module includes a module body 200 and an exemplary embodiment of a flow chamber 100 according to the present invention, the flow chamber 100 being fastened to the module body 200.

[0326] The module body 200 includes a lens 17 for coupling an input light beam incident on the ATR crystal 7 and coupling an output light beam reflected from the ATR crystal 7, wherein the lens 17 is, for example, composed of zinc selenide. Furthermore, the module body 200 includes an optical window 18 disposed between the ATR crystal 7 and the lens 17, wherein the optical window 18 is, for example, composed of zinc sulfide. The module body 200 also includes a fourth sealing element 19 disposed on the outer side of the module body 200 facing the flow chamber 100 and sealingly contacting the side of the flow chamber 100 facing the module body 200, wherein the fourth sealing element 19 is configured in the form of a circular ring (O-ring). Additionally, the module body 200 includes: a polarizer 20 for polarizing the light beam reflected from the ATR crystal 7 and subsequently coupled out; a motor 21 for rotating the polarizer 20; and two mirrors 22d and 22e.

[0327] The flow chamber 100 is secured to the module body 200 by a separate third fastener 12 and a stop element 23 arranged on the outer side of the module body 200 facing the flow chamber 100, wherein the stop element 23 has a stop surface against which the flow chamber 100 is pressed by the third fastener 12. Here, the third fastener 12 is a cylindrical head screw. The cylindrical head screw is arranged such that the angle between the main extension direction of the cylindrical head screw (or the third fastener 12) and the first outer side of the base 1 is 40° to 65°. In addition, the angle between the stop surface and the first outer side of the base 1 is 40° to 50°. Furthermore, the aperture 4 has a protruding region 13 that protrudes beyond the second outer side of the base 1 adjacent to the first outer side of the base 1, wherein the protruding region 13 presses against the stop surface of the stop element 23. Here, a recess 5 is arranged between the second outer side of the base 1 and the third fastener 12.

[0328] The flow chamber 100 can be easily and securely connected to the module body 200 using the third fastener 12 and the stop element 23. Here, the third fastener 12 is installed at an angle to the first outer side of the base 1, such that the flow chamber 100 presses against the module body 200 and the stop surface of the stop element 23 at an angle; that is, the first force component is directed towards the module body 200, and the second force component is directed towards the stop surface. The stop surface can now be arranged at a corresponding angle to the first outer side of the base 1 to effectively absorb the force component applied to the stop surface by the third fastener 12 and redirect it towards the module body 200. This method achieves a very secure fixation.

[0329] The spectrometer also includes a light source 24, a photodetector 25, a beam splitter 26, three mirrors 22a, 22b, and 22c, and two parabolic mirrors 27a and 27b.

[0330] Example 5

[0331] Figure 5 A cross-sectional view of an exemplary embodiment of a spectrometer according to the present invention is shown. The spectrometer includes an exemplary embodiment of an optical module 1000 according to the present invention (in... Figure 5 (Indicated by a dashed box in the image), the optical module includes a module body 200 and an exemplary embodiment of a flow chamber 100 according to the present invention, the flow chamber 100 being fastened to the module body 200.

[0332] The module body 200 includes a lens 17 for coupling an input light beam incident on the ATR crystal 7 and coupling an output light beam reflected from the ATR crystal 7, wherein the lens 17 is, for example, made of zinc selenide. Furthermore, the module body 200 includes an optical window 18 disposed between the ATR crystal 7 and the lens 17, wherein the optical window 18 is, for example, made of zinc sulfide. The module body 200 also includes a fourth sealing element 19 disposed on the outer side of the module body 200 facing the flow chamber 100 and sealingly contacting the side of the flow chamber 100 facing the module body 200, wherein the fourth sealing element 19 is configured in the form of a circular ring (O-ring). Additionally, the module body 200 includes two reflectors 22d and 22e.

[0333] The flow chamber 100 is secured to the module body 200 by a separate third fastener 12 and a stop element 23 arranged on the outer side of the module body 200 facing the flow chamber 100, wherein the stop element 23 has a stop surface against which the flow chamber 100 is pressed by the third fastener 12. Here, the third fastener 12 is a cylindrical head screw. The cylindrical head screw is arranged such that the angle between the main extension direction of the cylindrical head screw (or the third fastener 12) and the first outer side of the base 1 is 40° to 65°. In addition, the angle between the stop surface and the first outer side of the base 1 is 40° to 50°. Furthermore, the aperture 4 has a protruding region 13 that protrudes beyond the second outer side of the base 1 adjacent to the first outer side of the base 1, wherein the protruding region 13 presses against the stop surface of the stop element 23. Here, a recess 5 is arranged between the second outer side of the base 1 and the third fastener 12.

[0334] The flow chamber 100 can be easily and securely connected to the module body 200 using the third fastener 12 and the stop element 23. Here, the third fastener 12 is installed at an angle to the first outer side of the base 1, such that the flow chamber 100 presses against the module body 200 and the stop surface of the stop element 23 at an angle; that is, the first force component is directed towards the module body 200, and the second force component is directed towards the stop surface. The stop surface can now be arranged at a corresponding angle to the first outer side of the base 1 to effectively absorb the force component applied to the stop surface by the third fastener 12 and redirect it towards the module body 200. This method achieves a very secure fixation.

[0335] The spectrometer also includes a light source 24, two photodetectors 25a and 25b, a polarizer 28 inside the spectrometer, a beam splitter 26, four mirrors 22a, 22b, 22c and 22f, and three parabolic mirrors 27a, 27b and 27c.

[0336] Example 6

[0337] Figure 6 A portion of another exemplary embodiment of the flow chamber according to the invention is shown in a side sectional view. In this embodiment, the flow chamber includes a filter element 15 disposed in a recess between the ATR crystal 7 and an opening connected to the inlet and / or between the ATR crystal 7 and an opening connected to the outlet. The filter element 15 is arranged in direct contact with a spacer 16 disposed, preferably applied to the ATR crystal. For clarity, Figure 6 Only the ATR crystal 7, filter element 15, and spacer 16 are shown; all other components of the flow chamber are not included. Figure 6 As shown in the diagram. The spacer 16 can be applied to the ATR crystal 7 in the form of a grid or a strip, wherein the arrangement of the spacer 16 on the ATR crystal 7 adapts to the structured portion of the ATR crystal 7, which has the structured portion on the side facing the aperture, and such that the spacer is arranged only in areas that are not reached (or illuminated) by the optical beam 29 during optical measurement due to the structured portion (or the geometry of the structured portion) of the ATR crystal 7. Therefore, the optical path through the geometry of the ATR crystal 7 (or the geometry of the structured portion) is selected such that unilluminated areas are generated on the upper side of the ATR crystal, where the spacer 16 is applied.

[0338] A filter element 15 (e.g., in the form of a filter membrane) is applied to the spacer retainer 16. The spacer retainer 16 can be manufactured by various methods, such as photolithography, 3D printing, or CNC machining. For example, the spacer retainer 16 can be a photoresist coating.

[0339] Example 7

[0340] Figure 7a Another exemplary embodiment of the flow chamber according to the present invention is shown in a side sectional view of the flow chamber 100.

[0341] The flow chamber 100 includes a substrate 1 having an inlet 2 for the analyte and an outlet 3 for the analyte, and an aperture 4 disposed on a first outer side of the substrate 1. The aperture 4 is fastened (or bonded) to the substrate 1 by means of at least one adhesive material.

[0342] The matrix 1 and the pore size 4 are preferably composed of different materials with different coefficients of thermal expansion. The matrix 1 is preferably a polymer matrix (e.g., made of "BioMed Clear" by formlabs). The pore size is preferably composed of an alloy, such as stainless steel.

[0343] A recess 5 is provided on the first outer side of the substrate 1, the recess containing a flow chamber measuring cavity that is fluidly connected to the inlet 2 and the outlet 3. An aperture 4 is arranged on the first outer side of the substrate 1, and the recess 5 containing the flow chamber measuring cavity is also provided on this first outer side. Therefore, the recess 5 with the flow chamber measuring cavity is adjacent to the aperture 4. In the region of the aperture 4, an aperture ring 6 is also configured such that the aperture ring 6 is adjacent to the recess 5.

[0344] Figure 7b It shows Figure 7a The enlarged portion shows an enlarged side view of the recess 5 and the elements arranged within it. The flow chamber 100 also includes a device consisting of an ATR crystal 7 and a first sealing element 8 for sealing the flow chamber measurement cavity, the device being sandwiched between the aperture 4 and a first wall region of the recess 5 facing the aperture 4. Here, the first sealing element 8 is arranged on the side of the ATR crystal 7 facing away from the aperture 4 and makes sealing contact with the ATR crystal 7 and the first wall region of the recess 5. The central wall region of the recess facing the aperture 4 has an opening connected to the inlet 2 and an opening connected to the outlet 3.

[0345] The ATR crystal 7 (e.g., composed of silicon) may include multiple microprisms and has a structured portion with V-grooves or recesses on the side facing the aperture. The first sealing element 8 is composed of a polymer material (e.g., ethylene-propylene-diene rubber or silicone) and is configured in the form of a circular ring (O-ring).

[0346] Furthermore, the flow chamber 100 includes a separate fastener 12 for securing the flow chamber to the module body of the optical module. The fastener 12 is a head screw. This head screw is arranged such that the angle between the main extension direction of the head screw (or fastener 12) and the first outer side of the substrate 1 is 40° to 65°. Additionally, the aperture 4 has a protruding region 13 that protrudes beyond the second outer side of the substrate 1 adjacent to the first outer side of the substrate 1. Here, a recess 5 is arranged between the second outer side of the substrate 1 and the fastener 12. Furthermore, the aperture also has an additional sealing element 14 that is arranged around the fastener 12 and sealingly connected to it.

[0347] Furthermore, the flow chamber 100 also includes a filter element 15 disposed in the recess 5 between the ATR crystal 7 and the opening connected to the inlet 2, and between the ATR crystal 7 and the opening connected to the outlet 3. The filter element 15 may preferably be fastened to the first sealing element 8. The filter element 15 may be, for example, a cellulose filter element having a thickness of 0.02 mm to 0.2 mm.

[0348] The analyte guided through the flow chamber may contain large molecules (such as proteins), cellular residues, and microorganisms. These substances may deposit on the ATR crystal, leading to biocontamination. Deposits or biocontamination can further degrade measurements because the deposited components contribute an excessively large signal in the measurement or measurement spectrum, thus affecting measurement quality. Furthermore, deposits on the ATR crystal can contaminate the analyte at that location in subsequent measurements.

[0349] The filter element 15 keeps larger molecules (e.g., proteins), cellular residues, and microorganisms in the analyte away from the ATR crystal 8, as these components are trapped by the filter element 15, while smaller molecules relevant to optical measurements pass through. Therefore, deposits or biocontamination on the ATR crystal 7 are better avoided. Thus, the filter element 15 also better prevents contamination of the flow chamber and the analyte within it. Furthermore, the filter element 15 keeps air bubbles present in the analyte away from the ATR crystal 7, as these bubbles, when attached to the ATR crystal 7, can also have undesirable effects on the measurement or the measured spectrum.

Claims

1. A flow chamber (100) for optical measurement, comprising a substrate (1) having at least one inlet (2) and at least one outlet (3) and an aperture (4) disposed on a first outer side of the substrate (1), wherein a recess (5) is provided on the first outer side of the substrate (1), the recess comprising a flow chamber measurement cavity connected to the at least one inlet (2) and the at least one outlet (3), in, The flow chamber (100) further includes a device for clamping between the aperture (4) and at least one first wall region of the recess (5), the device including an ATR crystal (7) and at least one first sealing element (8) for sealing the flow chamber measurement cavity, wherein the at least one first sealing element (8) is disposed on the side of the ATR crystal (7) opposite to the aperture (4). in, - The substrate (1) is composed of at least one material having a first coefficient of thermal expansion, and the aperture (4) is composed of at least one material having a second coefficient of thermal expansion different from the first coefficient of thermal expansion, wherein the aperture (4) can be fixed at the substrate (1) at at least one first fixing point by at least one first fastener (9), such that the substrate (1) and the aperture (4) are fixed at the at least one first fixing point in the x-direction parallel to the first outer side of the substrate (1), in the y-direction parallel to the first outer side of the substrate (1), and in the y-direction perpendicular to the substrate (1). The first outer extension of the body (1) is substantially immobile relative to each other in the z-direction, and the aperture (4) is fixed at the base (1) at at least one second fixing point by at least one second fixing member (10), such that the base (1) and the aperture (4) are substantially immobile relative to each other in the z-direction at the at least one second fixing point, and are only partially movable relative to each other in the x-direction and the y-direction, respectively, so that the different expansion and / or contraction of the components of the flow chamber (100) that occur during temperature changes can be compensated. and / or - The flow chamber (100) includes at least one filter element (15) arranged in the recess (5) between the ATR crystal (7) and at least one opening connected to the at least one inlet (2) and / or between the ATR crystal (7) and at least one opening connected to the at least one outlet (3).

2. The flow chamber (100) according to the preceding claim, characterized in that, The aperture (4) can be fixed at the base (1) at the at least one second fixing point by the at least one second fixing member (10) such that the base (1) and the aperture (4) at the at least one second fixing point are substantially immobile relative to each other in the z direction, and can move relative to each other in the x direction and the y direction by at least 0.01 mm, preferably at least 0.05 mm, particularly preferably at least 0.1 mm, and / or at most 1 mm, preferably at most 0.8 mm, particularly preferably at most 0.5 mm.

3. The flow chamber (100) according to any one of the preceding claims, characterized in that, - The at least one first fastener (9) is selected from the group consisting of countersunk screws and combinations thereof, wherein the at least one first fastener (9) is preferably at least one countersunk screw, and / or - The at least one second fastener (10) is selected from the group consisting of a semi-circular head screw, a rivet, a cylindrical head screw and combinations thereof, wherein the at least one first fastener (10) is preferably at least one semi-circular head screw.

4. The flow chamber (100) according to any one of the preceding claims, characterized in that, - At least one material constituting the matrix (1) is at least one polymer, preferably selected from the group consisting of polyetheretherketone, polytetrafluoroethylene, polypropylene, polysulfone, polyethersulfone, polycarbonate, polyvinyl chloride, polylactic acid, polyamide, thermoplastic polyurethane, acrylonitrile-butadiene-styrene, UV-curable synthetic resins and mixtures thereof, and / or - At least one material comprising the aperture (4) is selected from the group consisting of metals, such as iron; alloys, preferably iron-containing alloys, such as stainless steel; polymers, such as polyetheretherketone; and mixtures and combinations thereof, wherein the aperture (4) preferably comprises stainless steel or is composed of stainless steel.

5. The flow chamber (100) according to any one of the preceding claims, characterized in that, The ATR crystal (7) - Contains or is composed of at least one material, said at least one material being at least partially transparent to light with wavelengths of 2µm to 20µm, preferably 4µm to 12µm, wherein said ATR crystal (7) preferably contains or is composed of at least one material selected from the group consisting of silicon, diamond, germanium, zinc selenide, zinc sulfide and mixtures and combinations thereof, wherein said ATR crystal (7) particularly preferably contains or is composed of silicon, and / or - Includes multiple microprisms, and / or - A structured portion (7a) is provided on the side facing the aperture, preferably a structured portion (7a) with a groove or recess.

6. The flow chamber (100) according to any one of the preceding claims, characterized in that, - The at least one first sealing element (8) • Contains or consists of at least one polymer, said at least one polymer being selected from: the group consisting of ethylene-propylene-diene rubber, silicone, and mixtures thereof, and / or • Constructed in the form of a circular ring, and / or • It is in sealed contact with at least one first wall region (5) of the ATR crystal (7) and / or the recess. and / or - The flow chamber (100) includes at least one second sealing element (11) arranged around the recess (5), wherein the at least one second sealing element (11) preferably • Contains or consists of at least one polymer, said at least one polymer being selected from: the group consisting of ethylene-propylene-diene rubber, silicone, and mixtures thereof, and / or • Constructed in the form of a circular ring, and / or • At least partially arranged in another recess, said other recess being arranged around said recess (5) and located on the first outer side of said base (1), and / or • It is in sealed contact with the substrate (1) and / or the aperture (4).

7. The flow chamber (100) according to any one of the preceding claims, characterized in that, The at least one filter element (15) - Selected from: cellulose filter elements, such as cellulose filter elements made from regenerated cellulose; paper filter elements; Glass fiber filter elements; cellulose acetate filter elements; polyethersulfone filter elements; nylon filter elements; polyvinylidene fluoride filter elements; polytetrafluoroethylene filter elements; polypropylene filter elements; polycarbonate filter elements; and combinations thereof, wherein the at least one filter element is preferably selected from: the group consisting of cellulose filter elements, paper filter elements, glass fiber filter elements, and combinations thereof, and / or - It has a thickness of 0.001mm to 5mm, preferably 0.01mm to 1mm, and particularly preferably 0.02mm to 0.2mm.

8. The flow chamber (100) according to any one of the preceding claims, characterized in that, The flow chamber (100) further includes at least one filter holder (16) for holding the at least one filter element (15), the at least one filter holder being disposed between the ATR crystal (7) and the at least one filter element (15). The at least one filter holder (16) preferably has a grid structure and a frame extending around the grid structure, wherein - The frame is in contact with the ATR crystal (7), and the grid structure is not in contact with the ATR crystal (7), wherein the grid structure is preferably arranged at a distance of 0.001 mm to 5 mm, preferably 0.005 mm to 2 mm, particularly preferably 0.008 mm to 1 mm, and extremely preferably 0.01 mm to 0.1 mm from the ATR crystal (7), and / or - The at least one filter element (15) is held between the frame and at least one second wall region of the recess (5) facing the aperture (4), and / or - The central wall region of the recess (5) facing the aperture (4) has at least one retaining element, preferably at least two retaining elements, wherein the at least one filter element (15) is held between the grid structure and the at least one retaining element (15).

9. The flow chamber (100) according to any one of claims 1 to 7, characterized in that, The at least one filter element (15) is arranged to be in direct contact with at least one photoresist coating (16) applied to the ATR crystal (7), wherein preferably - The at least one photoresist coating (16) has a thickness of 0.1µm to 100µm, preferably 1µm to 50µm, particularly preferably 5µm to 20µm, and / or - The at least one photoresist coating (16) is applied to the ATR crystal (7) in the form of a grid or strip, wherein the arrangement of the photoresist coating (16) on the ATR crystal (7) preferably adapts to the structured portion of the ATR crystal (7), the ATR crystal (7) having the structured portion on the side facing the aperture (4), and / or - The at least one filter element (15) is fastened to the at least one first sealing element (8), preferably connected to the at least one first sealing element (8) in a material-fit manner.

10. The flow chamber (100) according to any one of the preceding claims, characterized in that, The recess (5) - Arranged between the at least one first fixing part and the at least one second fixing part, wherein the at least one first fixing part and the at least one second fixing part preferably have the same distance from the recess (5), and / or - The central wall region of the recess (5) facing the aperture (4) has a structured portion, preferably a serrated structured portion, and / or - The central wall region of the recess (5) facing the aperture (4) has at least one opening connected to the at least one inlet (2), and / or - The central wall region of the recess (5) facing the aperture (4) has at least one opening connected to the at least one outlet (3).

11. The flow chamber (100) according to any one of the preceding claims, characterized in that, The flow chamber (100) includes at least one third fastener (12), preferably a separate third fastener (12), for securing the flow chamber (100) to the module body of the optical module, wherein - The at least one third fastener (12) has a main extending direction, wherein the angle between the main extending direction and the first outer side of the base (1) is 20° to 85°, preferably 30° to 70°, particularly preferably 40° to 65°, and / or - The at least one third fastener (12) is selected from the group consisting of headstock screws, roundhead screws, and combinations thereof, wherein the at least one third fastener (12) is preferably at least one headstock screw, particularly preferably a single headstock screw, and / or - The aperture (4) has a protruding region (13) that protrudes beyond the second outer side of the base (1), wherein the recess (5) is preferably arranged between the second outer side of the base (1) and the at least one third fastener (12), and / or - The flow chamber (100) also has at least one third sealing element (14), which is arranged around the at least one third fastener (12) and is sealed to the at least one third fastener (12).

12. An optical module (1000) comprising a module body (200) and a flow chamber (100) according to any one of the preceding claims, the flow chamber being fastened to the module body.

13. The optical module (1000) according to claim 12, characterized in that, The flow chamber (100) is fastened to the module body (200) by at least one third fastener (12), preferably a single third fastener (12), and a stop element (23) disposed on the outer side of the module body (200) facing the flow chamber (100), wherein the stop element (23) has a stop surface, and the flow chamber (100) is pressed against the stop surface by the at least one third fastener (12), and wherein preferably - The angle between the stop surface and the first outer side of the base (1) is 20° to 85°, preferably 30° to 65°, particularly preferably 40° to 50°, and / or - The at least one third fastener (12) has a main extending direction, wherein the angle between the main extending direction and the first outer side of the base (1) is 20° to 85°, preferably 30° to 70°, particularly preferably 40° to 65°, and / or - The at least one third fastener (12) is selected from the group consisting of headstock screws, roundhead screws, and combinations thereof, wherein the at least one third fastener (12) is preferably at least one headstock screw, particularly preferably a single headstock screw, and / or - The aperture (4) has a protruding region (13) that protrudes beyond the second outer side of the base (1), wherein the protruding region (13) presses against the stop surface, and wherein the recess (5) is preferably arranged between the second outer side of the base (1) and the at least one third fastener (12), and / or - The flow chamber (100) also has at least one third sealing element (14) arranged around the at least one third fastener (12).

14. The optical module (1000) according to claim 12 or 13, characterized in that, The main body of the module (200) - Includes a lens (17) for coupling an input light beam incident on the ATR crystal (7) and for coupling an output light beam reflected from the ATR crystal (7), wherein the lens (17) preferably comprises or is composed of zinc selenide, and / or - Includes an optical window (18) disposed between the ATR crystal (7) and the lens (17), wherein the optical window (18) preferably comprises or is composed of zinc sulfide, and / or - Includes at least one fourth sealing element (19), said at least one fourth sealing element being arranged on the outer side of the module body (200) facing the flow chamber (100) and in sealing contact with the side of the flow chamber (100) facing the module body (200), wherein said at least one fourth sealing element (19) is preferably configured in the form of a circular ring, and / or - Includes a polarizer (20) for polarizing the beam reflected from the ATR crystal (7) and subsequently coupled out.

15. A spectrometer comprising at least one light source, at least one photodetector, and an optical module (1000) according to any one of claims 12 to 14, wherein the spectrometer is preferably an FTIR spectrometer or a QCL-based infrared spectrometer.

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