Apparatus for determination of optimal reaction parameters of photochemical reactions in photoreactive substance samples and method of operating the apparatus
Patent Information
- Application Number
- EP2024758713
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-08-04
- Filing Date
- 2024-08-01
- Publication Date
- 2025-11-05
Smart Images
Figure EP2024071826_13022025_PF_FP_ABST
Abstract
Description
[0001] Device for determining optimal reaction parameters of photochemical reactions in photoreactive substance samples and method for operating the device
[0002] The invention relates to a device for determining optimal reaction parameters of photochemical reactions in photoreactive substance samples and a method for operating the device.
[0003] When conducting photochemical reactions, analysis is helpful for determining which wavelength is absorbed by the respective reaction mixture and is ultimately photochemically relevant, as well as for understanding the influence of temperature on the reaction process. In some photochemical reactions, multiphase reaction mixtures are photochemically reacted, such as in photocatalysis, which requires uniform mixing. The amount of starting material available for analysis is often limited, primarily due to low product availability or high material costs.
[0004] Based on this, it is the object of the present invention to provide a device for determining optimal reaction parameters of a photochemical reaction of several photoreactive substance samples under comparable conditions.
[0005] This object is achieved by a device having the features of claim 1.
[0006] The further object, an analysis method for photoreactive substance samples during the performance of a photochemical reaction under comparable conditions, is achieved by the method having the features of independent claim 18.
[0007] Further developments of the device and the method are set out in the respective subclaims.
[0008] The device according to the invention for determining optimal reaction parameters for photochemical reactions in photoreactive substance samples comprises, according to a first embodiment, a receiving container with a holder device having an arrangement of receiving openings for cuvettes. It also comprises a first temperature control device designed to control the temperature of the cuvettes, which are arranged in the receiving openings of the receiving container when conducting an analysis, to a predetermined first temperature. Furthermore, the device comprises a light module with an arrangement of light-emitting semiconductor components. This arrangement is designed and provided to irradiate the cuvettes.Finally, it comprises a second temperature control device for controlling the temperature of the light-emitting semiconductor components to a predetermined second temperature, as well as a control unit for the light-emitting semiconductor components, which is connected at least to the second temperature control device. The receiving container and the light module are arranged relative to one another such that each receiving opening in the arrangement of receiving openings corresponds to at least one of the light-emitting semiconductor components in the arrangement of light-emitting semiconductor components, so that light emitted by each light-emitting semiconductor component passes through the corresponding receiving opening.
[0009] "Determination of optimal reaction parameters for photochemical reactions in photoreactive substance samples" refers to testing or screening by which photochemical reactions can be triggered in multiple substance samples containing at least one photoreactive substance by exposure to light from the UV or visible spectrum. The term "photoreactive" is intended to encompass all photon-induced or assisted chemical reactions, i.e., not only actual photochemical reactions in which molecules enter an excited state by absorbing photons, which triggers a chemical reaction, but also catalytic photoreactions, photoinduced, and photoassisted catalytic reactions.
[0010] "Cuvettes" are defined as any type of vial or bottle suitable for containing photoreactive substances. They typically have a capacity in the range of 0.5 ml to 10 ml, but can also be larger or smaller. The cuvettes are made of a material that is transparent to the wavelengths of the radiation emitted by the light module.
[0011] "Light-emitting semiconductor devices" can be all types of LEDs (light-emitting diodes) or other devices capable of emitting light with wavelengths in the range from ultraviolet to infrared. Therefore, LEDs refer to all such "LEDs" in this context.
[0012] The "first temperature" corresponds to the temperature that the substance sample in the cuvette should have while the device is in operation during screening. The "second temperature" corresponds to an operating temperature intended for the diodes, referred to below as the diode temperature for short, which is generally different from the first temperature. The first and second temperatures can lie within a predetermined range with corresponding tolerance limits. The temperature range for the first temperature depends on the photochemical reaction being investigated, or rather on the chemical reactions induced or assisted by photons, since the actual photochemical reaction, in which molecules enter an excited state through the absorption of photons, is almost temperature-independent. The temperature range for the second temperature or diode temperature extends from 0 °C to +60 °C, if necessary.to +80 °C, but preferably between +20 °C and +40 °C to avoid temperature-dependent performance changes of the diodes.
[0013] Advantageously, the device according to the invention allows the cuvettes to be temperature-controlled by the two temperature control devices without the LEDs being affected by condensation, icing, or excessive temperatures. For this purpose, the control unit can be configured to control the second temperature control device depending on the substance sample temperature in such a way that the diode temperature is maintained at its predetermined value. The device according to the invention thus allows fundamental photochemical investigations for research and development in industry and science to be carried out in a material-saving and cost-effective manner because multiple irradiation experiments can be conducted in parallel and simultaneously with very small sample quantities. The second temperature control device thermally decouples the LEDs from the receiving container containing the cuvettes.This advantageously prevents or reduces temperature drift of the light-emitting semiconductor elements during continuous operation, preferably to a maximum of 0.6 °C, which would otherwise lead to a change or reduction in light intensity and thus impair accurate measurements. According to a further embodiment, each cuvette is assigned a light-emitting semiconductor element. Alternatively, each cuvette can be assigned a group of at least two light-emitting semiconductor elements; preferably, each cuvette is assigned three to four LEDs in order to be able to introduce the desired light output into the cuvettes depending on the application.
[0014] According to yet another embodiment of the device according to the invention, the light module has an arrangement of optical elements. Each of the light-emitting semiconductor components is assigned at least one optical element, which is designed to focus or align radiation emitted by the light-emitting semiconductor components onto the associated cuvettes. In one possible embodiment, this comprises a configuration with groups of light-emitting semiconductor elements, each of which can then be assigned a focusing / alignment optical system, so that several light-emitting semiconductor elements forming a group are arranged together under one optical element, which focuses / aligns the radiation from the several light-emitting semiconductor elements onto the associated cuvette. The optical element can preferably be selected from a group comprising at least one converging lens, a Fresnel lens, and a fiber optic system.
[0015] According to a further embodiment of the device according to the invention, the light module has at least one fluid line for the flow of a temperature control fluid, which is guided in a temperature control circuit that provides the second temperature control device. The fluid line can be a temperature control channel, a hose, or even a pipe. The aforementioned fluid lines can be integrated into the housing or partially installed therein as components separate from the housing. This ensures that the temperature control fluid flows through the light module, creating direct temperature control.
[0016] According to an alternative embodiment of the device according to the invention, the light module is connected on its side facing away from the receiving container to a cooling plate, which provides the second temperature control device. For this purpose, the light module has at least one thermal interface made of one or more thermally conductive materials between the light-emitting semiconductor components and the cooling plate. The cooling plate can comprise a thermally conductive material and be connected to at least one electrical cooling element (e.g., a Peltier element). Additionally or alternatively, the cooling plate can be equipped with external and / or internal heat transfer surfaces, past which a cooling fluid flows, thus convectively dissipating heat. For example, the cooling plate can also be designed with a temperature control channel for the flow of a temperature control fluid, wherein the walls of the temperature control channel form internal heat transfer surfaces.Additionally or alternatively, the cooling plate may have outward-facing ribs that provide external heat transfer surfaces, e.g., with the ambient air. Furthermore, the cooling plate may be designed as a replaceable cooling pack or to accommodate a replaceable cooling pack.
[0017] According to yet another embodiment of the device according to the invention, the light module delimits an emission space in which the array of LEDs is arranged, and has at least one opening optically connected to the emission space and facing the receiving container, wherein the opening is sealed by a pane transparent to the light from the LEDs, wherein the LEDs are arranged on a surface of the emission space opposite the transparent pane. It is understood that instead of a common light exit opening for all LEDs, the housing can have a separate, assigned opening for each light-emitting semiconductor component, each of which is closed by a transparent pane, wherein the arrangement of the openings corresponds to the arrangement of the LEDs.The emission chamber is connected to the at least one fluid line for the flow of the temperature control fluid, with the light-emitting semiconductor components in direct contact with the temperature control fluid. An electrically non-conductive temperature control fluid is used for this purpose. This enables a temperature control fluid circuit for direct temperature control. The "optical connection" of the emission chamber to the at least one opening means that there is either direct "line of sight" between the LEDs in the emission chamber and the openings, or that the light module has optical steering or guiding elements, e.g., optical fibers, through which the light emitted by the LEDs reaches the openings.
[0018] According to yet another embodiment of the device according to the invention, the first temperature control device of the receiving container is at least one temperature control element arranged in the receiving container. This temperature control element can be a heating and / or cooling element (e.g., an electric heating element or a Peltier element) that is in thermally conductive contact with the cuvettes via a thermal interface, such as a temperature control bath. The thermal interface can be provided by a thermally conductive material of the receiving container and / or the holder device or by a stationary temperature control bath with a heat-conducting medium. "Stationary temperature control bath" here means without circulation or circuit and without connection to an external or separate heat source or sink outside the receiving container.Alternatively, the first temperature control device can have a separate heat source or heat sink, which, together with the receiving container, forms a temperature control circuit with a circulating temperature control fluid, so that the cuvettes in the receiving container are located in a flowing temperature control bath. Alternatively, the receiving container consists of a heat-conducting material block in which the receiving openings and a temperature control channel are formed, which is closed at the top by the holder device designed as a plate, which has receiving openings corresponding to the receiving openings formed in the receiving container. The first temperature control device is designed to temperature-control the cuvettes in the receiving openings of the receiving container to the predetermined first or substance sample temperature, which lies within a temperature range of -25 °C to +180 °C, preferably within a temperature range of -20 °C to +150 °C.Advantageously, the cuvettes can be tempered for an optimal reaction temperature without having to take the diode temperature into account, since the thermal decoupling achieved by the second tempering device prevents any impairment of the LEDs due to condensation, icing or overtemperature.
[0019] According to a preferred embodiment, the device according to the invention can provide for the receiving container to be arranged above the light module. The cuvettes can thus be irradiated from below and are easily accessible from above for inserting and removing the cuvettes from the corresponding receiving openings, or for taking samples during the reaction.
[0020] According to an alternative embodiment of the device according to the invention, the light module can also be arranged above the receiving container. This alternative offers the possibility of, for example, arranging a stirrer plate device below the receiving container, so that a magnetic stirrer can be used in each cuvette to stir the substance sample present there.
[0021] In both cases, according to a further development, a thermally insulating separating plate can be provided between the receiving container and the light module to support the thermal decoupling of the receiving container and the light module. To allow the light from the light module to reach the receiving container, the separating plate can be made of transparent material or have through-openings whose arrangement corresponds to that of the LEDs or the receiving openings and which can be closed with a transparent pane. The separating plate is designed either as a transparent pane or as an insulator plate with through-openings that are arranged corresponding to the light-emitting semiconductor elements and the receiving openings and are closed with transparent panes.
[0022] If enhanced thermal decoupling between the receptacle and the light module is not required, alternative developments allow for the omission of a thermally insulating partition plate or the use of a partition plate that is not thermally insulating, such as one made of metal. Of course, a partition plate made of a thermally non-insulating, non-transparent material also has through-holes whose arrangement corresponds to the arrangement of the LEDs or the receptacle openings, and which can be closed with a transparent pane.
[0023] According to yet another embodiment of the device according to the invention, the semiconductor components emit light with wavelengths in a range from 250 nm to 650 nm, i.e. from the ultraviolet to the visible "red" range. At least two light-emitting semiconductor components - or analogously, the light-emitting semiconductor components of at least two groups - emit light of the same wavelength, so that in one case all light-emitting semiconductor components emit light of the same wavelength. Alternatively, it can also be provided that each light-emitting semiconductor component, or each group of the at least two light-emitting semiconductor components, emits light of a different wavelength. In this way, the cuvettes can advantageously be irradiated with the desired wavelength. Test irradiations with different wavelengths are also possible.
[0024] Furthermore, the light intensity of each light-emitting semiconductor component or of the at least two light-emitting semiconductor components of each group can be adjusted by the control unit. This allows the intensity of each wavelength of two or more light-emitting semiconductor components or two or more groups to be coordinated with one another using the control unit, so that the irradiation intensity can be adjusted even with the LEDs' different efficiencies depending on the wavelength. The efficiency describes the ratio of the radiant power to the absorbed power and currently varies between 10% (green, 530 to 540 nm), 20% (blue, 440 nm), and 70% (red, from 650 nm). The efficiency of LEDs in the UV wavelength range is currently a maximum of 10%.However, the invention is not limited to LEDs with the aforementioned efficiencies, as continuous developments in this field lead to higher efficiencies, so that a device according to the invention can naturally also incorporate LEDs with higher efficiencies developed in the future. By controlling the power consumption, the irradiation intensity of the LEDs can be adjusted at different wavelengths.
[0025] The control unit also allows each light-emitting semiconductor component to be individually controlled via a touch panel on the control unit, allowing its intensity or light output to be adjusted, for example, by dimming. Furthermore, the simultaneous control of all light-emitting semiconductor components is possible.
[0026] According to yet another embodiment of the device according to the invention, the light module comprises a housing and a cassette in which the array of light-emitting semiconductor components is arranged. The cassette is detachably arranged in the housing and may have a handle. This cassette makes it easy to exchange different arrays of light-emitting semiconductor components.
[0027] According to yet another embodiment of the device according to the invention, the optical elements are arranged directly above the associated light-emitting semiconductor components, for example, on the circuit board. This applies to both the design of the light module with and without a cassette. Alternatively or additionally, the optical elements can be arranged in the through-openings of the partition plate located between the light module and the receptacle.
[0028] The second temperature control device, which thermally decouples the LEDs from the cuvettes, making it easier to maintain the predetermined second or diode temperature, can be integrated into such a cassette or into the housing of the light module as a boundary of the receiving opening for the cassette or the cassette compartment.
[0029] If the second temperature control device is intended for the direct temperature control of the light-emitting semiconductor elements, it will in any case be integrated into the cassette, which will then have corresponding connections for connecting the fluid lines to the temperature control circuit.
[0030] Furthermore, according to a preferred embodiment, this cassette has at least one fluid channel connected to the emission chamber in which the array of light-emitting semiconductor components is arranged. Alternatively or additionally, a connection of the light-emitting semiconductor components to a connection element on the housing can be provided by a detachable plug connection between the cassette and the housing.
[0031] A second temperature control device for indirect temperature control can be configured either in the cassette or in the housing of the light module adjacent to the cassette compartment. The device according to the invention can therefore comprise multiple arrangements of light-emitting semiconductor elements or multiple cassettes, each containing an arrangement of light-emitting semiconductor elements, which can be inserted alternately in the light module. Preferably, one cassette can comprise light-emitting semiconductor components that all emit light or radiation of the same wavelength, and in another cassette (exchange cassette), each light-emitting semiconductor component can emit a different wavelength.
[0032] The arrangement of light-emitting semiconductor components can, for example, comprise one by three, i.e. three, or five by five, i.e. 25, or three by three, i.e. nine, light-emitting semiconductor components or groups of at least two LEDs, which can emit light or radiation with nine different wavelengths simultaneously when the exchange cassette is used.
[0033] According to yet another embodiment of the device according to the invention, the cassette comprises a cassette housing and a cassette lid closing the cassette housing, in which passage openings are formed corresponding to the arrangement of the light-emitting semiconductor components. Then, according to yet another embodiment of the device according to the invention, the optical elements can be arranged in the passage openings of the cassette lid, alternatively or in addition to the optical elements arranged directly above the light-emitting semiconductor components. According to yet another embodiment of the device according to the invention, a transparent pane is arranged alternatively or additionally on a side of the cassette lid facing the light-emitting semiconductor components.In this case, a spacer plate with through-openings in which the light-emitting semiconductor components are accommodated is arranged in the cassette, wherein the through-openings of the spacer plate are designed to limit the radiation angle of the emitted radiation.
[0034] Furthermore, in yet another embodiment of the device according to the invention, the receiving container and the light module each have at least one temperature sensor operatively coupled to the control unit, which is further connected to the first temperature control device of the receiving container. The temperature sensors enable monitoring, control, and ultimately regulation of the temperature control devices.
[0035] According to yet another embodiment, the device according to the invention comprises a vibrating plate on which the receiving container and the light module are arranged, and which can be operated by the control unit. The vibrating plate is part of a vibrating device. The vibrating plate allows the arrangement of receiving container and light module to be vibrated in an oscillating manner by the control unit for a predetermined time and frequency. Depending on the substance to be tested, this enables thorough mixing and uniform irradiation of the substance samples, especially for viscous substances and those prone to phase separation. The oscillating movement of the vibrating plate prevents unwanted shear forces on the substance.
[0036] Furthermore, according to yet another embodiment, the receiving container has a lid that is at least partially closed. A completely closed lid is useful, for example, to prevent the escape of temperature control fluid when the vibrating plate is activated. Furthermore, a completely closed lid offers protection against escaping radiation emitted by the light-emitting semiconductor components, which passes through the cuvettes without absorption, especially in the arrangement in which the receiving container sits on the light module. Alternatively, the lid can also have through-openings for easy sample removal from the cuvettes. The invention further relates to a method for operating a device for determining optimal reaction parameters of a photochemical reaction in photoreactive substance samples using a device according to the invention.This device comprises at least one receiving container with a holder device containing an arrangement of receiving openings for cuvettes. The receiving container further comprises a first temperature control device designed to control the temperature of the cuvettes that can be arranged in the receiving openings of the receiving container to a predetermined first temperature. The device further comprises a light module with an arrangement of light-emitting semiconductor components that are designed to irradiate the cuvettes that can be arranged in the receiving openings of the receiving container, and it has a second temperature control device for controlling the temperature of the LEDs to a predetermined second temperature. In addition, it has a control unit for the LEDs, which is connected at least to the second temperature control device.
[0037] In a first embodiment, the method according to the invention comprises the following steps:
[0038] - Inserting cuvettes filled with samples of photoreactive substances into the receptacles of the holder device of the receiving container, whereby the cuvettes can be filled with the samples of photoreactive substances after insertion or also beforehand;
[0039] - Tempering the cuvettes by means of the first tempering device to the predetermined first temperature,
[0040] - Irradiation of the cuvettes and thus the samples of photoreactive substances by the light-emitting semiconductor elements of the light module,
[0041] - depending on the predetermined temperature, tempering the light-emitting semiconductor elements with the second tempering device to the predetermined second temperature.
[0042] The light-emitting semiconductor components can be LEDs.
[0043] The two temperature control units allow precise temperature control of the cuvettes between -25 °C and +180 °C, preferably between -20 °C and +150 °C, without impairing the function or performance of the light-emitting semiconductor components such as LEDs, thus ensuring accurate measurement results. To effectively determine the optimal reaction parameters, multiple samples can be tested simultaneously. For example, one reaction parameter can be varied at a time, while the other conditions can be kept the same for all samples. This allows, for example, several substance samples of the same composition to be irradiated simultaneously with different wavelengths in one experiment.
[0044] According to yet another embodiment of the method according to the invention, the control unit controls the LEDs which emit radiation of different wavelengths in the range from 250 nm to 650 nm in such a way that an equal irradiation intensity is set by adjusting the absorption power of the LEDs as a function of a wavelength-dependent efficiency.
[0045] According to yet another embodiment, the method according to the invention also provides for the vibration frequency and duration of the vibrating plate to be controlled by the control unit. To ensure thorough mixing of the substance samples, the vibrating plate can be vibrated in an oscillating manner.
[0046] Advantageously, the method according to the invention makes it possible to determine the optimal wavelength for a defined reaction process of the photoreactive substance to be investigated by first inserting a cassette containing the arrangement of LEDs with different wavelengths into the light module. Furthermore, the cassette used initially with the arrangement of LEDs with different wavelengths can be exchanged in a subsequent step for a cassette containing light-emitting semiconductor components that all emit radiation of the same wavelength, allowing further investigations, such as concentration determinations, to be carried out.
[0047] Further embodiments of the device, as well as some of the advantages associated with these and other embodiments, will become clear and better understood from the following detailed description with reference to the accompanying figures. Items or parts thereof that are substantially the same or similar may be provided with the same reference numerals. The figures are merely a schematic representation of one embodiment of the invention.
[0048] Showing:
[0049] Fig. 1 is a perspective view of the device according to the invention with a vibrating device, and Fig. 2 is a schematic sectional view of the device according to the invention,
[0050] Fig. 3 is a perspective view of the device according to the invention according to an alternative embodiment with section planes ll and ll-ll drawn in,
[0051] Fig. 4 is a perspective partially exploded view of the device according to the invention from Fig. 3,
[0052] Fig. 5 is a perspective view of a light module cassette of the device according to the invention from Fig. 3,
[0053] Fig. 6 is a perspective partially exploded view of the light module cassette from Fig. 5, Fig. 7 is a sectional view of the device according to the invention along the sectional plane II of Fig. 3,
[0054] Fig. 8 is a sectional view of the device according to the invention along the section plane II-II of Fig. 3,
[0055] Fig. 9 a perspective detail rear view of the light module,
[0056] Fig. 10 is a perspective view of the device according to the invention from Fig. 3 with external heat source / heat sink,
[0057] Fig. 11 is a schematic sectional view of another device according to the invention with alternative first and second temperature control devices,
[0058] Fig. 12 is a schematic sectional view of another device according to the invention with a light module having an alternative second tempering device and an arrangement of optical elements,
[0059] Fig. 13 is a schematic sectional view of a light module cassette with an alternative arrangement of optical elements.
[0060] In Figs. 1 and 2, the device 1 according to the invention for optimizing reaction parameters of a photochemical reaction or improving photochemical reactions in photoreactive substance samples shows a receiving container 20 and a light module 30. Mounted in the receiving container 20 is a plate 22 as a holder device, which has nine receiving openings 21. These receiving openings 21 are arranged equidistantly in three by three spaces and are designed to hold cuvettes 4 into which photoreactive substance samples can be filled.
[0061] The cuvettes 4 there can - this is not shown figuratively - each contain 0.5 ml, but in other embodiments of the device 1 according to the invention and correspondingly other sizes or embodiments of the cuvettes, these can also contain more or fewer milliliters, for example volumes of 10 ml. The receiving container 20 from Fig. 1 has a lid 23 which can be opened for the arrangement and removal of the cuvettes 4 in the receiving openings 21 - it is shown in the opened position in Fig. 1 and can be closed to protect the cuvettes 4. In Fig. 2, the surface of the lid 23 is completely closed.
[0062] In Fig. 2, the lid 23 has through openings 23' above the cuvettes 4, which are aligned with the receiving openings 21 when the lid 23 is closed, so that the contents of the cuvettes 4 can be reached, for example, with a pipette.
[0063] The light module 30 is arranged below the receiving container 20 and is firmly connected to the receiving container 20, which has a transparent bottom or through-openings arranged corresponding to the receiving openings 21 and closed with transparent panes. The light module 30 has a housing 33 that is firmly mounted on a vibrating plate 51 of a vibrating device 50, here via angle plates 53 and screws. The vibrating device 50 further has a control unit 52 with which the frequency and duration of the oscillation of the vibrating plate 51 can be controlled. The frequency should not be selected too high; frequencies of up to a maximum of 600 rpm have proven suitable for a circularly vibrating platform shaker as the vibrating device 50.
[0064] The light module 30 here has a cassette 32 which is detachably connected to the housing 33 and can thus be pulled out.
[0065] Fig. 1 shows a bow-shaped handle 38 additionally provided on the cassette 32. As Fig. 2 shows, a circuit board or plate 39 with an array of LEDs 31 is arranged in the cassette 32, the light from which strikes the plate 22 with the inserted cuvettes 4 from below. The light from the LEDs 31 is shown in Fig. 2 with curved arrows. In the example shown in Fig. 2, the housing 33 of the light module 30 has a large opening 36' towards the receiving container 20 for the passage of the light. The opening 36' is covered with a disk 37 that is transparent to the radiation from the LEDs 31.Alternatively, a separating plate, preferably made of thermally insulating material, can be arranged between the receiving container 20 and the light module 30. This separating plate closes off the housing 33 of the light module 30 at the top and simultaneously forms the bottom of the receiving container 20. This separating plate is either designed as a transparent pane 37 or has through-openings arranged corresponding to the LEDs 31 or the receiving openings 21 and closed with transparent panes 37. Such a separating plate 36 with through-openings 36' is used as a cover for the housing 33 of the light module 30 in the example shown in Figs. 4 and 7.
[0066] The cassette 32 can be covered with glass or a pane transparent to the radiation from the LEDs 31—not shown in Fig. 2—so that the cassette 32 forms a sealed element and the light-emitting semiconductor components 31 are protected from dirt. Instead of a continuous transparent pane for all light-emitting semiconductor elements 31, the light module 30 or the cassette 32, in the alternative embodiment shown in Figs. 3 to 10, can have an associated passage opening with a correspondingly transparent pane for each light-emitting semiconductor element.
[0067] The receiving container 20 has a first temperature control device with which the interior of the receiving container 20 or the plate 22 or the cuvettes 4 can be temperature controlled in a temperature range from -25 °C to +180 °C, for example -20 °C to +80 °C.
[0068] In Fig. 2, the first temperature control device is designed as a temperature control bath and is schematically shown with supply and discharge lines 24 for a temperature control fluid to an external heating or cooling source 25. The temperature control fluid flows around the cuvettes 4 in the temperature control bath. In the illustrated arrangement with the light module 30 below the receiving container 20, when selecting the temperature control fluid for the first temperature control device, care must be taken to ensure that the temperature control fluid is sufficiently transparent for the wavelengths of the light-emitting semiconductor elements 31 used in the light module 30. To measure a substance sample temperature within the receiving container 20, the receiving container 20 has a temperature sensor 61, which can be arranged, for example, on an inner wall of the receiving container 20 or on the plate 22 adjacent to the receiving openings 21.
[0069] The light module 20 further comprises a second temperature control device with which the cassette 32 and thus the LEDs 31 can be temperature-controlled, i.e., cooled or heated, during operation. In Fig. 2, the second temperature control device is also designed as a temperature control bath and is schematically depicted with supply and discharge lines 34 for an additional temperature control fluid to an external cooling or heating source 35.
[0070] In general, the temperature control fluid of the second temperature control device can differ from the temperature control fluid of the first temperature control device, especially if the second temperature control device is designed for the direct temperature control of the light-emitting semiconductor elements. When selecting the temperature control fluid for the second temperature control device, particular attention should be paid to ensuring that the temperature control fluid is not only transparent to the wavelengths of the light-emitting semiconductor elements used in the light module, but is also electrically non-conductive. The second temperature control device also has a temperature sensor 62 for detecting a diode temperature, which is arranged on the circuit board 39. A fluid line 34' is formed in the housing 33 or the cassette 32 for the flow of a temperature control fluid, which is guided in a temperature control circuit with the supply and discharge lines 34.
[0071] Furthermore, the device 1 has a control unit 10, which is external here, but can also be mounted within the device 10—not shown in the drawing—and can be operatively coupled to the essential components it is intended to control, namely the light-emitting semiconductor elements 31, the first and second temperature control devices, and the vibrating device 50 or its control unit 52. For the sake of simplicity, the electrical and electronic connections required for this purpose are not specifically depicted in the drawing and are represented by the connecting line 11. The control unit 10 makes it possible to individually control the light-emitting semiconductor components 31 and to adjust the light intensity of each light-emitting semiconductor component 31 independently of one another.
[0072] The control unit 10 is further designed to control both the first and the second temperature control device. Thus, the first temperature control device temperatures the interior of the receiving container 20 to a substance sample temperature in a range from -25 °C to +180 °C and, depending on the substance sample temperature reached in the receiving container 20, the second temperature control device of the light module 30 is controlled such that the temperature of the light-emitting semiconductor elements 31 remains consistently below a predetermined limit temperature, the so-called diode temperature, which ideally remains in a range from +20 °C to +30 °C or up to +40 °C. Only through this thermal decoupling is it possible to operate the LEDs 31 with the same photon flux orto operate with a constant photon flux, since otherwise, the temperature control in the receiving container would lead to a temperature change at the LEDs 31 with increasing operating time, which would be associated with a change in the radiation intensity of the light-emitting semiconductor components 31, which could lead to falsified measurement results. Furthermore, the intensity of the light-emitting semiconductor components 31 of each wavelength can be coordinated with one another using the control unit 10, so that the irradiation intensity can be adjusted even with the different efficiencies of the LEDs 31 depending on the wavelength. For this purpose, the power consumption of the individual LEDs 31 is controlled depending on their efficiency in order to adapt the radiation power of the LEDs 31 to one another.
[0073] Figures 3 to 10 show an alternative embodiment of the device 1, in which the receiving container 20 consists of a heat-conducting material block with a molded-in temperature control channel 24", which extends in a meandering manner between two connection openings 24' and provides the first temperature control device. Between the turns of the temperature control channel 24", three times three through-openings 2T are formed in the receiving container 20 as a holder device for receiving the cuvettes. By arranging a plate 22, the temperature control channel 24" is closed at the top, wherein the plate 22 has three times three receiving openings 21, which, when arranged on the receiving container 20, are aligned with its receiving openings 2T. The receiving container 20 can, for example, be made of a metal block, e.g. aluminum, into which the temperature control channel 24" with the connection openings 24' and the receiving openings 2T are milled. Between the plate 22, which is also made of metal, e.g.Aluminum, and the receiving container 20, a sealing plate 26 is arranged to seal the temperature control channel 24", wherein the sealing plate 26 also has three times three recesses which correspond to the receiving openings 21 in the plate 22 and the receiving openings 2T in the receiving container 20. The temperature control channel 24" serves to conduct a temperature control medium in order to exchange heat via the metal wall of the receiving container 20 with the cuvettes received in the receiving openings 2T or the substance samples contained therein, ie to supply or dissipate it.
[0074] In the example shown in Figs. 3 to 10, a safety switch 27 is also arranged on the receiving container 20, which contacts a switch transmitter 27' when the lid 23 is closed in order to ensure that the device 1 can only be operated when the lid 23 is correctly closed.
[0075] In this device 1, too, the receiving container 20 is arranged on the light module 30. On the side facing the receiving container 20, the housing 33 of the light module 30 is terminated by a separating or insulating plate 36 made of thermally insulating material. The insulating plate 36 has three times three through-openings 36' corresponding to the arrangement of the receiving openings 21, 2T. In this example, as shown in Figs. 4 and 8, each through-opening 36' is designed as a through-bore for receiving a fiber optic 3T made of optical fibers as the optical element. On the side facing the receiving container 20, the through-opening 36' is widened to form a receptacle in which a transparent disk 37 made of glass or quartz is inserted and sealed by means of an O-ring 37', whereby only one disk 37 is shown as an example in Figs. 4 and 8.Advantageously, the fiber optics 3T can be used to introduce the photons of the respective LED 31 from the cassette 32 into a cuvette 4, which is received in the receiving opening 21, 2T on the disc 37.
[0076] Figs. 5 and 6 show the cassette 32 of the exemplary device 1 from Figs. 3 to 10. The cassette 32 has a cassette housing 32.1 and a cassette cover 32.2 closing the cassette housing 32.1. The cassette 32 is designed to be received in a correspondingly designed compartment in the housing 33 of the light module 30, so that the front side of the cassette 32, on which the handle 38, designed here as a ball knob, and the connections 34 of the second temperature control device are located, is flush with the front side of the housing 33 of the light module 30. The cassette housing 32.1, together with the cassette cover 32.2, delimits an emission chamber in which a circuit board 39 with the three times three LEDs 31 is arranged. A fluid line 34', which is designed here as an inlet or outlet opening in the cassette housing 32.2, connects the connections 34 to the emission chamber, so that a tempering fluid for tempering the LEDs 31 can be passed through the cassette 32.Furthermore, the compartment formed in the housing 33 of the light module 30 for receiving the cassette 32 is, as can be seen in Figs. 7 and 8, open at the bottom so that additional heat absorbed by the cassette housing 32.1 can be dissipated into the environment. For better heat dissipation, the cassette housing 32.1 is formed with ribs 32' on the underside, which provide heat-conducting surfaces for external convection cooling and complement the second temperature control device. In the cassette cover 32.2, three times three through-openings 32.3 are formed corresponding to the arrangement of the LEDs 31, through each of which a fiber optic 31' made of optical fibers also extends. The fiber optics 31' in the through-openings 32.3 of the cassette cover 32.2 and in the through-openings 36' of the insulator plate 36 are in contact. Alternatively, a fiber optic 31' made of optical fibers can extend continuously through the passage opening 32.3 in the cassette cover 32.2 and extend through the through-opening 36' in the insulator plate 36. On the other side, the cassette cover 32.2 rests against a transparent disc 32.4, which is inserted into the cassette housing 32.1 at a distance from the circuit board 39 with the LEDs 31 and is sealed by means of a circumferential seal 32.6. A spacer plate 32.5 arranged on the circuit board 39 has through-openings for accommodating the LEDs 31 in order to limit the radiation angle of the emitted radiation, so that the emitted radiation from each LED 31 strikes the fiber optic 31' in the respectively assigned through-opening 32.3.
[0077] The electrical connection of the circuit board 39 with the LEDs 31 is made from the rear of the light module 30, i.e., the side facing away from the handle 38 and the connectors 34. For this purpose, the cassette 32 is provided with a type of plug on the rear side, which, when the cassette 32 is arranged in the designated compartment of the light module 30, engages with a matching socket arranged accordingly in the compartment.
[0078] In Fig. 7 it can be seen that the housing 33 of the light module 30 has a cover plate 33' on the rear, which closes a connection chamber 33" formed in the housing 33. The connection chamber 33" has an opening to the cassette compartment on the inner wall. A connection element 39' provided on the cover plate 33' allows the connection of a socket board 39.2 via a terminal block 39.3, which is arranged with the terminal block 39.3 in the connection chamber 33". The socket board 39.2 is arranged on the inner wall of the connection chamber 33" so as to close the opening. The pin socket of a pin plug connection 39.4 extends from the socket board 39.2 through the opening in the inner wall of the connection chamber 33", as can be seen in Fig. 9, which shows the connection chamber 33" on the rear of the housing 33 without the cover plate 33', terminal block 39.3, and socket board 39.2. The pin plug of the pin plug connection 39.4 is connected to a plug board 39.1, which is attached externally to the rear of the cassette 32 or the cassette housing 32.1. The circuit board 39 is connected to the plug-in board 39 via a printed circuit board connector (not shown), wherein the printed circuit board connector extends through an opening formed in the rear wall of the cassette housing 32.1 and is sealed in a liquid-tight manner by the plug-in board 39.1.
[0079] As in Fig. 2, in Fig. 10 the first and the second temperature control device of the device 1 each have an external heating / cooling source 25, 35, which are connected via unlabeled connecting lines (shown schematically) to the connections 34 of the light module 30 and the connections 24 of the receiving container 20, which are hidden here and indicated by dotted lines.
[0080] Fig. 11 shows a device 1 according to the invention with alternative temperature control devices in the receiving container 20 and in the light module 30. Here, the second temperature control device of the light module 30 does not comprise a temperature control fluid that is guided in a temperature control circuit, but rather a cooling plate 35' arranged below the plate or circuit board 39 with the LEDs 31. The cooling plate 35' is connected to a cooling element 35", such as a Peltier element. A temperature control medium is provided in the receiving container 20 as a stationary temperature control bath, which is not circulated by an external heating / cooling source. In this embodiment of the first temperature control device, the temperature control medium is controlled by a temperature control element 25' that is also arranged in the receiving container 20 and is designed for heating and / or cooling.
[0081] The invention is not limited to the combinations of the first temperature control device of the receiving container and the second temperature control device of the light module shown in the figures. Rather, further alternatives (not shown figuratively) of the device according to the invention with the various combinations of the first and second temperature control devices described here are encompassed. For example, it is possible for the stationary temperature control bath shown in Fig. 11 to be combined as the first temperature control device of the receiving container 20 with a temperature control circuit as the second temperature control device of the light module 20 according to Figs. 1 to 10. A further alternative consists in a combination of the second temperature control device of the light module 20 shown in Fig. 11 with cooling plate 35' and cooling element 35" without a fluid cooling medium with one of the first temperature control devices of the receiving container 20 according to Figs. 1 to 10.Of course, further modifications of the device with respect to the temperature control devices are also possible within the scope of protection defined by the claims. For example, Fig. 12 illustrates a further variant of the second temperature control device of the light module 20, in which a temperature control circuit is guided through a temperature control channel 34" that is not connected to the emission chamber for directly cooling the LEDs 31. The temperature control channel 34" is formed in a cooling plate 35' and, with its wall surfaces, provides internal heat transfer surfaces. Another variant of the second temperature control device relates to a cooling plate 35' with external heat transfer surfaces, such as cooling fins, which can be designed similarly to the fins 32' on the cassette housing 32.1 in Fig. 8.
[0082] Furthermore, Fig. 12 and Fig. 13 show examples of further optical elements arranged corresponding to the LEDs 31 of the light module 20 in order to focus and / or align the radiation emitted by the LEDs 31 in the direction of the respectively assigned cuvettes 4. The optical elements in Fig. 12 are Fresnel lenses 31, which are arranged directly above each LED 31 on the circuit board 39.
[0083] The optical elements in Fig. 13 are shown as converging lenses 3T" arranged in the cassette cover 32.2 in the through-openings 32.3. Furthermore, a possible embodiment is illustrated here in which each optical element 3T" is assigned to an LED group 310, here consisting of three LEDs 31. The grouping of the LEDs 31 is independent of converging lenses as an optical element in a cassette cover. It is also possible to use light modules with grouped LEDs without optical elements or to combine them with other optical elements such as the aforementioned Fresnel lenses or fiber optics. Furthermore, these modifications are not limited to light modules 20 with cassette 32, but can also be implemented individually in light modules without cassette.
[0084] LIST OF REFERENCE SYMBOLS
[0085] I Device
[0086] 4 cuvettes
[0087] 10 Control unit
[0088] II Connecting line
[0089] 20 receptacles
[0090] 21 , 2T mounting holes
[0091] 22 plate
[0092] 23, 23' cover, through opening
[0093] 24, 24' connections first temperature control device, connection openings
[0094] 24" temperature control channel
[0095] 25, 25' heat / cold source first temperature control device, temperature control element
[0096] 25" thermal interface medium
[0097] 26 Sealing plate
[0098] 27, 27' safety switch, switch actuator
[0099] 30 light modules
[0100] 31 , 310 light-emitting semiconductor component or LED, LED group
[0101] 3T, 31", 3T" optical element / fiber optics, Fresnel lens, converging lens
[0102] 32, 32' cassette, ribs
[0103] 32.1. 32.2 Cassette housing, cassette cover
[0104] 32.3, 32.4 Passage opening, transparent pane
[0105] 32.5, 32.6 spacer plate, seal
[0106] 33, 33', 33“ housing, cover plate, connection chamber
[0107] 34, 34', 34" Connections second temperature control device, fluid line, temperature control channel
[0108] 35, 35', 35“ heat / cold source second temperature control device, cooling plate, cooling element
[0109] 36, 36' separator / isolator plate, opening
[0110] 37, 37' disc, O-ring
[0111] 38 handle
[0112] 39, 39' plate / board, connecting element
[0113] 39.1. 39.2 Connector board, socket board
[0114] 39.3, 39.4 terminal block, pin connector
[0115] 50 vibrating device
[0116] 51 vibrating plate
[0117] 52 Control unit for vibrating device
[0118] 53 Bracket / Angle plates 61, 62 Temperature sensors
Claims
PATENT CLAIMS 1. Device (1) for determining optimal reaction parameters of a photochemical reaction in photoreactive substance samples, wherein the device (1) - a receiving container (20) with a holder device having an arrangement of receiving openings (21, 2T) for cuvettes (4), and with a first temperature control device designed to control the temperature of the cuvettes (4) that can be arranged in the receiving openings (21, 2T) of the receiving container (20) to a predetermined first temperature, - a light module (30) with an arrangement of light-emitting semiconductor components (31) which is designed to irradiate the cuvettes (4), and with a second temperature control device for controlling the temperature of the light-emitting semiconductor components (31) to a predetermined second temperature, and - a control unit (10) of the light-emitting semiconductor components (31), which is connected at least to the second temperature control device, wherein the receiving container (20) and the light module (30) are arranged relative to one another in such a way that each receiving opening (21, 21') from the arrangement of the receiving openings (21, 2T) corresponds to at least one of the light-emitting semiconductor components (31) from the arrangement of the light-emitting semiconductor components (31), so that light emitted by each light-emitting semiconductor component (31) passes through the corresponding receiving opening (21, 2T).
2. Device (1) according to claim 1, characterized in that each cuvette (4) is assigned a light-emitting semiconductor element (31), or that each cuvette (4) is assigned a group (310) of at least two light-emitting semiconductor elements (31).
3. Device (1) according to claim 1 or 2, characterized in that the light module (30) has an arrangement of optical elements, wherein each of the light-emitting semiconductor components (31) are assigned at least one optical element which is designed to focus and / or align radiation emitted by the light-emitting semiconductor components (31) onto the assigned cuvettes (4), wherein the optical element is selected from a group comprising at least one converging lens (31"), a Fresnel lens (31") and a fiber optic (31').
4. Device (1) according to at least one of claims 1 to 3, characterized in that the light module (30) has at least one fluid line (34') for the flow of a tempering fluid, which is guided in a tempering circuit which provides the second tempering device.
5. Device (1) according to at least one of claims 1 to 4, characterized in that the light module (30) is connected on its side facing away from the receiving container (20) to a cooling plate (35') which provides the second temperature control device, wherein the cooling plate (35') comprises a heat-conducting material and - is connected to at least one electrical cooling element (35") and / or - has external and / or internal heat transfer surfaces (32', 34"), and / or - designed as a replaceable cooling pack or to accommodate a replaceable cooling pack.
6. Device (1) according to claim 5, characterized in that the light module (30) delimits an emission space in which the arrangement of the light-emitting semiconductor components (31) is arranged, and has at least one opening (36') which is optically connected to the emission space and faces the receiving container (20), wherein the opening (36') is sealed by a pane (37) which is transparent to the light of the light-emitting semiconductor components (31), wherein the light-emitting semiconductor components (31) are arranged on a surface of the emission space which is opposite the pane (37), wherein the emission space is provided with the at least one fluid line (34').
7. Device (1) according to at least one of claims 1 to 6, characterized in that the first temperature control device of the receiving container (20) - at least one temperature control element arranged in the receiving container (20) which is in heat-conducting contact with the cuvettes (4) by means of a thermal interface, wherein the temperature control element is a heating and / or cooling element, and the thermal interface is provided by a heat-conducting material of the receiving container (20) and / or a heat-conducting material of the holder device and / or by a stationary temperature control bath with a heat-conducting medium, or - has a separate heat source or heat sink, which forms a temperature control circuit with the receiving container (20) with a circulating temperature control fluid, wherein a flowing temperature control bath is provided in the receiving container (20), in which the cuvettes (4) are located, or the receiving container (20) consists of a heat-conducting material block, in which the receiving openings (2T) and a temperature control channel (24") are formed, which is closed at the top by the holder device designed as a plate (22), which has receiving openings (21) corresponding to the receiving openings (21') formed in the receiving container (20), wherein the first temperature control device is designed to maintain a predetermined first temperature in the cuvettes (4) that can be arranged in the receiving openings (21, 2T) of the receiving container (20), which first temperature control device is designed to maintain a predetermined first temperature in a temperature range from -25 °C to +180 °C, preferably in a temperature range from -20 °C to +150 °C.
8. Device (1) according to at least one of claims 1 to 5, characterized in that - the receiving container (20) with the holder device, which has the arrangement of receiving openings (21) for cuvettes (4), is arranged above the light module (30), or - the light module (30) is arranged above the receiving container (20), wherein a thermal barrier is provided between the receiving container (20) and the light module (30). a mixed insulating separating plate is arranged, which is designed either as a transparent disc (37) or as an insulator plate (36) with passage openings which are arranged corresponding to the light-emitting semiconductor elements (31) and the receiving openings (21) and are closed with transparent discs (37).
9. Device (1) according to at least one of claims 1 to 8, characterized in that the light-emitting semiconductor components (31) emit light with wavelengths in a range from 250 nm to 650 nm, wherein at least two semiconductor components (31) emit light of the same wavelength or each semiconductor component (31) emits light of a different wavelength, and / or the light intensity of each light-emitting semiconductor component (31) is adjustable by means of the control unit (10).
10. Device (1) according to at least one of claims 1 to 9, characterized in that the light module (30) has a housing (33) and a cassette (32) which can be detachably arranged in the housing (33) and in which the arrangement of light-emitting semiconductor components (31) is arranged.
11. Device (1) according to at least one of claims 2 to 10, characterized in that the optical elements (3T, 31", 3T") are arranged directly above the associated light-emitting semiconductor components (31).
12. Device (1) according to claim 9 or 11, characterized in that the cassette (32) has at least one fluid line (34') which is connected to the emission space in which the arrangement of the light-emitting semiconductor components (31) is arranged, and / or a connection of the light-emitting semiconductor components (31) to a connection element (39') on the housing (33) by a detachable plug connection (39.4) is provided between the cassette (32) and the housing (33).
13. Device (1) according to at least one of claims 9 to 12, characterized in that the cassette (32) has a cassette housing (32.1) and a cassette cover (32.2) closing the cassette housing (32.1), in which passage openings (32.3) are formed corresponding to the arrangement of the light-emitting semiconductor components (31).
14. Device (1) according to claim 13, characterized in that - the optical elements (31 31", 3T") are arranged in the passage openings (32.3), and / or - a transparent pane (32.4) rests on a side of the cassette cover (32.2) facing the light-emitting semiconductor components (31), and a spacer plate (32.5) with through-openings in which the light-emitting semiconductor components (31) are accommodated is arranged in the cassette (32), wherein the through-openings of the spacer plate (32.5) are designed to limit the radiation angle of the emitted radiation.
15. Device (1) according to at least one of claims 1 to 14, characterized in that the receiving container (20) and the light module (30) each have at least one temperature sensor (61, 62) which is operatively coupled to the control unit (10) which is connected to the first temperature control device of the receiving container (20).
16. Device (1) according to at least one of claims 1 to 15, characterized in that the device (1) has a vibrating plate (51) on which the receiving container (20) and the light module (30) are arranged, wherein the vibrating plate (51) can be actuated by means of the control unit (10).
17. Device (1) according to at least one of claims 1 to 16, characterized in that the receiving container (20) has a lid (23) which is at least partially closed or which has through openings (23') for taking samples from the cuvettes (4).
18. A method for operating a device (1) for determining optimal reaction parameters of a photochemical reaction in photoreactive substance samples using a device (1) according to at least one of claims 1 to 17, wherein the device (1): - a receiving container (20) with a holder device having an arrangement of receiving openings (21, 2T) for cuvettes (4), and with a first temperature control device designed to control the temperature of the cuvettes (4) that can be arranged in the receiving openings (21, 2T) of the receiving container (20) to a predetermined first temperature, - a light module (30) with an arrangement of light-emitting semiconductor components (31) which are designed to irradiate the cuvettes (4) which can be arranged in the receiving openings (21, 2T) of the receiving container (20), and with a second temperature control device for tempering the light-emitting semiconductor components (31) to a predetermined second temperature, and - a control unit (10) of the light-emitting semiconductor components (31), which is connected at least to the second temperature control device, comprising the steps - Inserting cuvettes (4) into the receiving openings (21, 2T) of the holder device of the receiving container (20), before or after filling the cuvettes (4) with samples of photoreactive substances, - tempering the cuvettes (4) by means of the first tempering device to the predetermined first temperature, - irradiating the cuvettes (4) and thus the samples of photoreactive substances by means of the light-emitting semiconductor elements (31) of the light module (30), - depending on the predetermined first temperature, tempering the light-emitting semiconductor elements (31) with the second tempering device to the predetermined second temperature.
19. The method according to claim 18, wherein the control unit (10) controls the light-emitting semiconductor components (31) which emit radiation of different wavelengths in the range from 250 nm to 650 nm in such a way that an equal irradiation intensity is set by adjusting the absorption power of the light-emitting semiconductor components (31) as a function of a wavelength-dependent efficiency.