DEVICE AND METHOD FOR CONTROLLING THE EXPOSURE OF A SAMPLE TO LIGHT

Abstract

The invention concerns, amongst others, a device (1) for specific illumination of at least one biological sample, the device (1) comprising a multitude of cavities (2), each cavity (2) representing an internal space (3) being capable of holding the biological sample. The internal spaces (3) are each partially surrounded by a wall element (4) comprising windows (5) for observing and/or illuminating the internal spaces (3). In order to protect the internal spaces (3) from the ingress of light, the wall element (4) comprises a light-proof material. Each window (5) comprises at least one switchable element (8) being of switchable color and/or light transmittance. By the switchable elements (8), light exposure of the biological sample in the internal space (3) of each cavity (2) can be controlled so that unintended light exposure can be effectively avoided when illumination of the sample does not occur and/or the device (1) is stored or transported.

Claims

1. Device for specific illumination of a biological sample, comprising: at least one internal space which is designed to hold at least one biological sample or which is designed to comprise at least one container designed to hold at least one biological sample, and further comprising at least one illumination means which is designed to emit at least one specific biologically active wavelength, wherein the internal space is at least partially surrounded by: at least one wall element and, except for at least one window for observing and/or illuminating the internal space, protected from the ingress of light by at least one light-proof material, wherein the at least one window comprises at least one switchable element being of switchable color and/or light transmittance.

2. The device according to claim 1, wherein the switchable element comprises at least one electrochromic material.

3. The device according to claim 2, wherein the switchable element comprises at least two different electrochromic materials.

4. The device according to claim 1, wherein the switchable element is a liquid crystal display (LCD) or an independently controlled segment of an LCD.

5. The device according to claim 1, wherein the switchable element comprises at least one light shutter.

6. The device according to claim 1, wherein the switchable element comprises at least two polarization filters, one of which being fixed and the other one being turnable in its plane.

7. The device according to claim 1, further comprising two or more internal spaces and two or more windows, wherein at least two of the internal spaces are each provided with at least one window, and wherein the at least one switchable element of each window is switchable independently.

8. The device according to claim 1 comprising the at least one container, wherein the container comprises two or more cavities designed to hold the at least one biological sample, each cavity being provided with at least one window, and wherein the at least one switchable element of each window is switchable independently.

9. The device according to claim 1, wherein the illumination means is disposed and/or aligned such that each illumination means is targeted at at least one selected biological sample, container, cavity and/or window.

10. The device according to claim 8, wherein the illumination means, the window and the cavity are disposed in an aligned arrangement.

11. The device according to claim 1, wherein the switchable element comprises or is coupled with at least one control element for controlling the illumination means and/or illumination of the biological sample in the internal space.

12. The device according to claim 1, wherein the wall element comprises at least two parts that are attached to each other by at least one interlockable connecting structure comprising a light-tight but gas-permeable opening.

13. The device according to claim 12, wherein the opening is a meander-shaped channel.

14. The device according to claim 12, wherein the opening comprises at least one gas-permeable filter element.

15. Method for specifically illuminating at least one biological sample comprising: illuminating the biological sample with at least one specific biologically active wavelength, wherein the sample is protected from light by at least one light-proof material and can be observed and/or illuminated through at least one window, wherein an exposure of the biological sample to light is controlled by changing a color and/or light transmittance of the window via at least one control unit, wherein said color, light transmittance and/or transparency can be switched between at least two states, a first state preventing light exposure of the sample and at least one second state allowing the exposure of the sample to light.

16. The device according to claim 2, further comprising two or more internal spaces and two or more windows, wherein at least two of the internal spaces are each provided with at least one window, and wherein the at least one switchable element of each window is switchable independently.

17. The device according to claim 2 comprising the at least one container, wherein the container comprises two or more cavities designed to hold the at least one biological sample, each cavity being provided with at least one window, and wherein the at least one switchable element of each window is switchable independently.

18. The device according to claim 3, further comprising two or more internal spaces and two or more windows, wherein at least two of the internal spaces are each provided with at least one window, and wherein the at least one switchable element of each window is switchable independently.

19. The device according to claim 3 comprising the at least one container, wherein the container comprises two or more cavities designed to hold the at least one biological sample, each cavity being provided with at least one window, and wherein the at least one switchable element of each window is switchable independently.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] FIG. 1 shows a schematic representation (longitudinal section) of an exemplary embodiment of a device according to the invention, wherein the device is a multi-well plate.

[0037] FIG. 2 shows a schematic representation (longitudinal section) of another exemplary embodiment of a device according to the invention, wherein a multi-well plate is disposed within the device.

[0038] FIG. 3 shows a schematic representation (longitudinal section) of a further exemplary embodiment of a device according to the invention comprising illumination means, wherein a cell culture flask is disposed within the device.

[0039] FIG. 4 shows a schematic representation (longitudinal section) of another exemplary embodiment of a device according to the invention, wherein the device is a bioreactor.

[0040] FIG. 5 shows a schematic representation (longitudinal section) of a further exemplary embodiment of a device according to the invention comprising illumination and ventilation means, wherein a multi-well plate is disposed within the device.

DESCRIPTION OF EXEMPLARY AND PREFERRED EMBODIMENTS OF THE INVENTION

[0041] FIG. 1 shows an exemplary embodiment of a device 1 according to the invention. The device 1 comprises a multitude of cavities 2 (“wells”), each cavity 2 representing an internal space 3 being capable of holding a biological sample. The cavities 2/internal spaces 3 are each partially surrounded by a wall element 4 which is open at the top of each internal space 3. At the bottom of each internal space 3, the wall element 4 comprises windows 5 for observing and/or illuminating the internal spaces 3. The biological sample can be introduced into the internal space(s) 3 through opening(s) 6. The openings 6 are covered by a lid 7 extending to all cavities 2. In order to protect the internal spaces 3 from the ingress of light, the wall elements 4 and the lid 7 comprise a light-proof material. Each window 5 comprises at least one switchable element 8 being of switchable color and/or light transmittance. Each switchable element 8 can be switched between a first state (“closed state”) and one or more second state(s) (“active state”). In the closed state light is blocked off from the internal space 3, while in the active state light can pass through the window 5 into and out of the internal space 3 in a controlled manner. By the switchable elements 8, light exposure of the biological sample in the internal space 3 of each cavity 2 can thus be controlled so that unintended light exposure can be effectively avoided when illumination of the sample does not occur and/or the device 1 is stored or transported. Moreover, light exposure of the biological sample in the internal space 3 can be tuned by the switchable element 8 when the sample is illuminated. In an advantageous embodiment of the invention, it may also be possible to observe the biological sample in the internal space 3 through an “open” window 5 by switching the corresponding switchable element 8 from the closed to the active state. Illumination of the internal spaces 3 is employed by means of an external light bar or array 9 comprising a multitude of illumination means 10 (e.g. LEDs), each of which being disposed underneath a window 5.

[0042] FIG. 2 shows another exemplary embodiment of a device 15 according to the invention. The device 15 comprises an internal space 16 which is surrounded by a wall element 17 comprising a light-proof material that protects the internal space 16 from the ingress of light. At the bottom of the device 15, the wall element 17 further comprises a windows 18 for observing and/or illuminating the internal space 16. The window 18 comprises a switchable element 19 being of switchable color and/or light transmittance. For example, the switchable element 19 may be a LCD panel or the like. The switchable element 19 can be switched between a first state (“closed state”) and one or more second state(s) (“active state”). In the closed state light is blocked off from the internal space 16, while in the active state light can pass through the window 18 into and out of the internal space 16 in a controlled manner.

[0043] A container 20 is placed within the internal space 16 of the device 15. The container 20 is designed to hold at least one biological sample, for example, a suspension including living cells. The container 20 may be a standard cell culture vessel comprising a plurality of cavities 21 (“wells”), for example, a 6-, 12-, 24- or 96-well plate. The cavities 21 of the container 20 are covered by a lid 22. By the switchable element 19, light exposure of the biological samples (cells) in the cavities 21 of the container 20 can be controlled so that unintended light exposure can be effectively avoided when illumination of the inner space 16 does not occur and/or the device 15 is stored or transported. Moreover, light exposure of the biological samples in the container 20 can be tuned by the switchable element 19 when the inner space 16 is illuminated from the outside. In an advantageous embodiment of the invention, it may also be possible to observe the cells in the container 20 through the window 18 by switching the switchable element 19 from the closed to the active state. Illumination of the internal space 16 is employed by means of an external light source, bar or array 23 comprising at least one of illumination means 24 (e.g. LEDs) that are disposed underneath the switchable element 19. The switchable element 19 is coupled to an electronic control unit (not shown) via contact elements 25 so that it can be easily switched between the closed and the active state. If the switchable element 19 comprises an electrochromic material, electrical currents can be applied to the material via the contact elements 25 to induce the desired state transitions.

[0044] FIG. 3 shows a further exemplary embodiment of a device 30 according to the invention. The device 30 comprises an internal space 31 which is surrounded by a wall element 32 comprising a light-proof material that protects the internal space 31 from the ingress of light. In this advantageous embodiment, the wall element 32 includes two parts 33, 34 that are attached to each other by at least one interlockable connecting structure 35 comprising a light-tight but gas-permeable opening 36 permitting ventilation of the internal space 31 without allowing light from the outside to enter the internal space 31. In this embodiment, the opening 36 is a meander-shaped channel. At the bottom of the device 30, the wall element 32 further comprises a window 37 for observing and/or illuminating the internal space 31. The window 37 comprises a switchable element 38 being of switchable color and/or light transmittance. For example, the switchable element 38 may be a LCD panel or the like. The switchable element 38 can be switched between a first state (“closed state”) and one or more second state(s) (“active state”). In the closed state light is blocked off from the internal space 31, while in the active state light can pass through the window 37 into and out of the internal space 31 in a controlled manner.

[0045] A container 39 is placed within the internal space 31 of the device 30. The container 39 is designed to hold at least one biological sample, for example, a suspension including living cells. The container 39 may be a standard cell culture flask. By the switchable element 38, light exposure of the biological sample (cells) in the container 39 can be controlled so that unintended light exposure can be effectively avoided when illumination of the inner space 31 does not occur and/or the device 30 is stored or transported. Moreover, light exposure of the biological sample in the container 39 can be tuned by the switchable element 38 when the inner space 31 is illuminated from the outside. In an advantageous embodiment of the invention, it may also be possible to observe the cells in the container 39 through the window 37 by switching the switchable element 38 from the closed to the active state. The device 30 is coupled to an external illumination unit 40 comprising a light source, bar or array 41, a control element 42, and a power source 43. The light bar 41 comprises a plurality of illumination means 44 (e.g. LEDs) that are disposed underneath the switchable element 38 for illuminating the internal space 31.

[0046] FIG. 4 shows another exemplary embodiment of a device 50 according to the invention. The device 50 is a stirred bioreactor comprising an internal space 51 which is surrounded by a wall element 52 comprising a light-proof material that protects the internal space 51 from the ingress of light. The device 50 is designed to hold in its internal space 51 a biological sample, for example, a suspension including living cells. On at least one side of the device 50, the wall element 52 comprises a window 53 for observing and/or illuminating the internal space 51. The window 53 is covered at the outside by a switchable element 54 being of switchable color and/or light transmittance. For example, the switchable element 54 may be a LCD panel or the like. The switchable element 54 can be switched between a first state (“closed state”) and one or more second state(s) (“active state”). In the closed state light is blocked off from the internal space 51, while in the active state light can pass through the window 53 into and out of the internal space 51 in a controlled manner. By the switchable element 54, light exposure of the biological sample (cells) in the internal space 51 can be controlled so that unintended light exposure can be effectively avoided when illumination of the inner space 51 does not occur and/or the device 50 is stored or transported. Moreover, light exposure of the biological sample in the in the internal space 51 can be tuned by the switchable element 54 when the inner space 51 is illuminated. In an advantageous embodiment of the invention, it may also be possible to observe or otherwise optically measure properties of the cells or the cell culture medium in the internal space 51 through the window 53 by switching the switchable element 53 from the closed to the active state. The internal space 51 of the device 50 can be illuminated by an external illumination unit 55 comprising a light source, bar or array 56 being equipped with illumination means 57. The illumination means can for example emit light of different spectral characteristics or wavelengths.

[0047] FIG. 5 shows a further exemplary embodiment of a device 60 according to the invention. The device 60 comprises an internal space 61 which is surrounded by a wall element 62 comprising a light-proof material that protects the internal space 61 from the ingress of light. In this advantageous embodiment, the wall element 62 includes two parts 63, 64 that are attached to each other by at least one interlockable connecting structure 65 comprising a light-tight but gas-permeable opening 66 permitting passive ventilation of the internal space 61 without allowing light from the outside to enter the internal space 61. In this embodiment, the opening 66 is a meander-shaped channel. A separating plate 67 is disposed within the internal space 61, dividing the internal space 61 into a lower internal space 68 and an upper internal space 69. The separating plate 67 is made of a light-proof material and comprises (at least one) or several windows 70 for observing and/or illuminating the upper internal space 69. The windows 70 each comprise a switchable element 71 being of switchable color and/or light transmittance, which is disposed underneath or in openings in the separating plate 67 in the lower internal space 68. For example, each switchable element 71 may comprise an optics layer comprising an electrochromic material (e.g. tungsten trioxide) wherein redox reactions convert non-absorbing molecules into light absorbing states and vice versa. Electrical currents can be applied to the material to induce these transitions, but are not required to maintain the status of the material. They thus have a memory effect. Accordingly, each switchable element 71 is equipped with an electrochromic optics layer that can be independently switched between an opaque and a clear state by applying a lower voltage. In the opaque state light is blocked off from the upper internal space 69, while in the clear state light can pass through the windows 70 into and out of the upper internal space 69 in a controlled manner.

[0048] A container 72 is placed on the separating plate 67 within the upper internal space 69 of the device 60. The container 72 is designed to hold at least one biological sample, for example, a suspension including living cells. The container 72 may be a standard cell culture vessel comprising a plurality of cavities 74 (“wells”), for example, a 24- or 96-well plate. The cavities 74 of the container 72 are covered by a lid 75. Illumination of the upper internal space 69 is employed by means of an internal light source, bar or array 76 comprising a plurality of illumination means 77 (e.g. LEDs). The internal light bar 76 is disposed underneath the switchable elements 71 within the lower internal space 68, wherein the illumination means 77 are aligned underneath the windows 70. Light exposure of the biological samples (cells) in each cavity 74 of the container 72 can be tuned independently by the corresponding switchable element 71 when the upper inner space 69 is illuminated by the illumination means 77. In an advantageous embodiment of the invention, it may also be possible to observe the cells in the container 72 through the windows 70 via at least one camera (not shown) by switching the switchable elements 71 from the opaque to the clear state.

[0049] The device 60 further comprises cooling fins 78 for passive cooling of the inner space 61 and a fan 80 for active ventilation of the upper internal space 69. The cooling fins 78 are disposed on the top of the upper part 63 of the wall element 62 at the outside of the device 60. The fan 79 is arranged in a first ventilation opening 80 which is covered within the upper internal space 69 by a gas-permeable first filter element 81 being designed to avoid contamination of the internal space 61. At least one of the fan 79 and the filter element 81 is light-tight so as to protect the internal space 61 from the ingress of light. For pressure compensation, a second ventilation opening 82 is disposed opposite to the first ventilation opening 80. The second ventilation opening 82 is equipped with a light-tight but gas-permeable second filter element 83 being designed to avoid contamination of the internal space 61 as well. The active ventilation system allows for maintaining optimal conditions for, e.g., cultivating living cells, within the upper internal space 69, e.g. when the device 60 is positioned in a cell culture incubator providing an atmospheric environment controlled for its gas composition, temperature and humidity.

REFERENCES

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