Optical analysis device for point-of-care diagnostics, and method for operating same
The optical analysis device uses multibandpass filters to enhance multiplex detection in point-of-care diagnostics by creating multiple optical channels for simultaneous pathogen analysis, addressing the limitation of conventional devices.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- ROBERT BOSCH GMBH
- Filing Date
- 2025-12-12
- Publication Date
- 2026-06-18
Smart Images
Figure EP2025086838_18062026_PF_FP_ABST
Abstract
Description
[0001] R. 415710
[0002] - 1 -
[0003] Description
[0004] title
[0005] Optical analysis device for point-of-care diagnostics and methods for its operation
[0006] The present invention relates to an optical analysis device. Furthermore, the present invention relates to a method for operating the optical analysis device.
[0007] State of the art
[0008] In devices for decentralized point-of-care diagnostics, particularly using PCR tests, multiplex tests can simultaneously detect a large number of different pathogens. These multiplex tests typically employ different fluorophores with specific excitation and emission spectra. To prevent cross-referencing of fluorophore emissions, however, such devices can only have a limited number of optical channels. An optical channel is defined as a combination of optical filters with a defined excitation and emission spectrum. The transmission spectrum of each excitation filter is typically assigned to only one transmission spectrum of an emission filter, with the transmission spectra being shifted relative to each other by the Stokes shift of the fluorophore being analyzed by the optical channel.Such optical channels are called diagonal or conventional channels. R. 415710.
[0009] - 2 -
[0010] Disclosure of the invention
[0011] The optical analysis device comprises a light source, in particular a white light source, a sample carrier, and an optical sensor, in particular a camera. A first filter carrier with f first optical multibandpass filters is arranged in a beam path between the light source and the sample carrier. The first optical multibandpass filters are in particular double bandpass filters. A second filter carrier with f second optical multibandpass filters is arranged in a beam path between the sample carrier and the optical sensor. The second optical multibandpass filters are in particular double bandpass filters. Here, f is a natural number and at least 2, preferably at least 3. Each multibandpass filter allows the transmission of light in several different wavelength bands; when using double bandpass filters, this applies to two wavelength bands.Each wavelength band of a first multibandpass filter and each wavelength band of a second multibandpass filter form an optical channel. In particular, there are no overlaps between the wavelength bands of the first multibandpass filter and, in particular, there are no overlaps between the wavelength bands of the second multibandpass filter.
[0012] This optical analysis device enables the realization of many optical channels, especially for multiplex detection of several pathogens, through the use of various fluorophores tailored to the optical channels.
[0013] It is preferred that the optical analysis device comprises m*f, i.e., a number m times f, of fluorophores, which may be positioned upstream of the optical analysis device, particularly in chambers and / or reagent bars, where m corresponds to the number of bands that the multibandpass filters allow to pass through. If the multibandpass filters are double bandpass filters, then preferably 2*f fluorophores are present. These are configured to be brought into contact with a sample positioned on the sample carrier. If the sample is a nucleic acid sample, such as DNA or RNA, in particular, then the fluorophores may be attached to molecular beacons to prevent coupling of the sample. R. 415710
[0014] - 3 -
[0015] To enable the use of fluorophores on target nucleic acids, the target nucleic acids can be labeled with fluorophores, thus allowing for fluorescence spectrometric detection of the nucleic acid. In this context, the nucleic acids can serve as indicators for the presence of pathogens. A Stokes shift of a fluorophore corresponds to a wavelength difference between a wavelength band that passes through the first multibandpass filter of an optical channel and a wavelength band that passes through the second multibandpass filter of the same optical channel. This wavelength difference is determined by the distance between the respective centers of the two wavelength bands. Therefore, in fluorescence analysis of the sample, light emitted from the light source and passing through the first double bandpass filter of an optical channel can excite a fluorophore to fluoresce.The wavelength of the fluorescence light is then shifted relative to the wavelength of the excitation light so that the fluorescence light can pass through the second multibandpass filter of this optical channel and reach the optical sensor, while the excitation light cannot pass through the second multibandpass filter of the optical channel.
[0016] Furthermore, the optical analysis device is preferably configured to perform sample amplification, particularly by means of qPCR. For this purpose, amplification reagents are placed in the optical analysis device, and the optical analysis device includes at least one heat source to heat the sample in the presence of the amplification reagents. Amplification has the advantage that even a small amount of nucleic acid in the sample can be increased through several amplification cycles to such an extent that reliable detection of the nucleic acid, and thus, for example, of a pathogen, becomes possible.
[0017] The multibandpass filters and the fluorophores used are preferably matched such that no two optical channels include both the same first optical multibandpass filter and the same second multibandpass filter. In other words, any two channels can share at most one optical multibandpass filter. This advantageously prevents the beam paths of two channels from sharing both R. 415710
[0018] - 4 - pass through the same multibandpass filter of the first filter carrier as well as through the same multibandpass filter of the second filter carrier. This advantageously prevents fluorescence radiation from two different fluorophores from reaching the sensor simultaneously, or in other words, ensures that only the fluorescence radiation of one fluorophore reaches the sensor at any given time.
[0019] If all multibandpass filters are double bandpass filters, namely 2*f for the first double bandpass filter and 2*f for the second double bandpass filter, then the wavelength bands that pass through the first double bandpass filter and the wavelength bands assigned to them in an optical channel that pass through the second double bandpass filter can be numbered from 1 to 2*f, where these numbers correspond to the numbers of the optical channels. The numbering of the wavelength bands for the first double bandpass filter and for the second double bandpass filter proceeds from 1 to 2*f in ascending or decreasing wavelength ranges, respectively.In other words, the wavelength bands for which the first double bandpass filters are transparent are arranged in ascending or descending order according to their wavelength ranges and numbered from 1 to 2*f, while the wavelength bands for which the second double bandpass filters are transparent are arranged in ascending or descending order according to their wavelength ranges and numbered from 1 to 2*f. It is preferred that the first filter carrier has a first double bandpass filter for the wavelength bands or optical channels 1 and 2f and further first double bandpass filters for the pairings of wavelength bands or optical channels n and n+f-1, where 2 < n < f. The second filter carrier has second double bandpass filters that allow the pairings of wavelength bands or optical channels n and n+f to pass, where 1 < n < f.This choice of the two wavelength bands for each first double bandpass filter and each second double bandpass filter minimizes any possible crosstalk between the optical channels.
[0020] To capture the fluorescence light from the sample as effectively as possible, the beam path runs between the sample holder and the optical sensor R. 415710
[0021] - 5 - preferably orthogonal to a plane of the sample carrier. The beam path between the light source and the sample carrier is then angled relative to the sample carrier. In order to enable a compact design of the optical analysis device in view of these structural constraints, it is preferred that the first filter carrier is a filter wheel and the second filter carrier is a filter slider.
[0022] The optical analysis device is preferably designed as a microfluidic device. In such a microfluidic device, the sample carrier and reagents intended to come into contact with a biological sample, such as amplification reagents and fluorophores, can be placed in a replaceable disposable cartridge, while the light source, the optical sensor, and the two filter carriers do not come into contact with the sample and can therefore be reused.
[0023] In the method for operating the optical analysis device, a sample is placed on the sample holder and excited to fluorescence by means of the light source. The light emitted by the sample is detected by the optical sensor, and a fluorescence analysis of the sample is performed in m*f optical channels. If all multibandpass filters are double bandpass filters, a fluorescence analysis of the sample is performed in 2*f optical channels. The optical channels can be selected by adjusting the filter holders, so that with each change of optical channel, a different first double bandpass filter is placed in the beam path between the light source and the sample holder and / or a different second double bandpass filter is placed in the beam path between the sample holder and the optical sensor.
[0024] Before performing the fluorescence analysis, the sample is preferably brought into contact with m*f fluorophores so that a fluorescence response to the emission of excitation light can be expected in each optical channel.
[0025] Brief description of the drawings R. 415710
[0026] - 6 -
[0027] Exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description.
[0028] Figure 1 schematically shows elements of an optical analysis device according to an embodiment of the invention.
[0029] Figure 2 shows in two diagrams wavelength bands which optical double bandpass filters of an optical analysis device according to an embodiment of the invention can pass through.
[0030] Figure 3 shows in a diagram excitation spectra and emission spectra of fluorophores used in an optical analysis device and in a method according to embodiments of the invention.
[0031] Exemplary embodiments of the invention
[0032] Elements of an optical analysis device according to an embodiment of the invention are shown in Figure 1. This device includes a light source 11, for example a white LED, which is configured to shine light at an angle of 45° onto a sample carrier 12. An optical sensor 13, for example a camera, is arranged above the sample carrier 12. A first filter carrier 20 in the form of a filter wheel is arranged between the light source 11 and the sample carrier 12. This filter carrier has three optical double bandpass filters 21-23. A second filter carrier 30 in the form of a filter slider is arranged between the sample carrier 12 and the optical sensor 12. This filter carrier has three second optical double bandpass filters 31-33.The illustration of two differently hatched, adjacent areas in the double bandpass filters 21, 22, 23, 31, 32, 33 of the two filter carriers 20, 30 is intended only to show that each double bandpass filter allows two wavelength bands to pass through and does not imply any spatial separation of the transmittance of the two wavelength bands. The sample carrier 12 is designed as a microarray arranged in a disposable microfluidic cartridge (not shown). This cartridge contains amplification reagents and, for example, six different fluorophores coupled to molecular beacons. (R. 415710.)
[0033] - 7 - The biological sample to be examined for pathogens is first digested in the microfluidic disposable cartridge to release the nucleic acids it contains. These are then amplified, and the target nucleic acids to be detected are coupled to the fluorophores. Each fluorophore serves as a probe for a target nucleic acid to be detected. A first beam path 51 runs from the light source through the first filter carrier 20 and a window of the microfluidic cartridge onto the sample carrier 12 and the sample 40 placed on it. A second beam path 52 runs from the sample carrier 12 through the window and onward through the second filter carrier 30 to the optical sensor 13.
[0034] The optical analysis device allows the amplified sample 40 to be examined in six optical channels. Each fluorophore is assigned one optical channel. Figure 2 shows in two diagrams the wavelengths X at which the double bandpass filters 21-23 and 31-33 each allow a transmission T of light. The upper diagram shows the wavelength bands 61-66 of the first double bandpass filter 21-23. The lower diagram shows the wavelength bands 71-76 of the second double bandpass filter 31-33. Since each of the double bandpass filters 21-23, 31-33 allows two wavelength bands 61-66, 71-76 to pass through, a total of six double bandpass filters 21-23, 31-33 result in twelve wavelength bands 61-66, 71-76. Each wavelength band 61-66 of a first double bandpass filter 21-23 correlates via the Stokes shift of its associated fluorophore with a wavelength band 71-76 of a second double bandpass filter 31-33.This is illustrated in Figure 2 by connecting lines between the wavelength bands. As shown in Table 1 below, this results in six optical channels.
[0035] R. 415710
[0036] - 8 -
[0037] Table 1
[0038] In the configuration of the first filter carrier 20 shown in Figure 1, its double bandpass filter 22 is located in the first beam path 51. The second filter carrier 30 is configured such that its double bandpass filter 31 is located in the second beam path 52. As shown in Figure 2, the first double bandpass filter 22 allows two wavelength bands 62, 64 to pass through, and the second double bandpass filter 31 allows two wavelength bands 71, 74 to pass through. Since a fluorophore in a wavelength band 64 of the first double bandpass filter 22 is excited to emit light whose wavelength lies in a wavelength range 74 of the second double bandpass filter 31, this configuration of the two filter carriers 20, 30 enables a fluorescence analysis of the sample 40 in the optical channel 4.
[0039] Figure 3 shows side-by-side the excitation light spectra of the six fluorophores (dashed lines) and their emission light spectra (solid lines). Figure 3 also shows which first double bandpass filters 21–23 allow which excitation wavelengths to pass and which second double bandpass filters 31–33 allow which emission wavelengths to pass. The resulting relationship between the double bandpass filters 21–23 and 31–33 and the optical channels is shown in Table 2. R. 415710
[0040] - 9 -
[0041] Table 2
[0042] Since the two filter carriers each have a number of f = 3 double bandpass filters 21 - 23, 31 - 33, the first filter 21 fulfills the condition that it filters light of the
[0043] Channels 1 and 2*f = 2*3 = 6 pass through. The first two optical filters 22, 23 each allow light from one channel n and another channel n+f-1 = n+3-1 = n+2 to pass through. The double bandpass filters 31 - 33 each allow light from one channel n and another channel n+f = n+3 to pass through.
[0044] As can be seen further from Table 2, the double bandpass filters 21-23, 31-33 and the fluorophores are matched such that no two optical channels include both the same first optical double bandpass filter 21, 22, 23 and the same second double bandpass filter 31, 32, 33. Any two of the six optical channels will include at most one common optical double bandpass filter 21-23, 31-33.
Claims
R. 415710 - 10 - Claims 1. Optical analysis device, in particular for point-of-care diagnostics, comprising a light source (11), a sample carrier (12) and an optical sensor (13), wherein a first filter carrier (20) with f first optical multibandpass filters (21-23) is arranged in a beam path (51) between the light source (11) and the sample carrier (12), and a second filter carrier (30) with f second optical multibandpass filters (31-33) is arranged in a beam path (52) between the sample carrier (12) and the optical sensor (13), wherein f is at least 2, and wherein a wavelength band (61-66) of a first multibandpass filter (21-23) and a wavelength band (71-76) of a second multibandpass filter (31-33) each form an optical channel.
2. Optical analysis device according to claim 1, characterized in that the first filter carrier (20) is a filter wheel and the second filter carrier (30) is a filter slide.
3. Optical analysis device according to claim 1 or 2, characterized in that it is a microfluidic device.
4. Optical analysis device according to one of claims 1 to 3, characterized in that it has m*f fluorophores for contacting a sample (40) to be positioned on the sample carrier (12), wherein m corresponds to the number of bands that the multibandpass filters (21-23, 31-33) allow to pass through, wherein the multibandpass filters (21-23, 31-33) and the fluorophores are matched to each other such that no two optical channels comprise both the same first optical multibandpass filter (21-23) and the same second multibandpass filter (31-33).
5. Optical analysis device according to one of claims 1 to 4, characterized in that a Stokes shift of a fluorophore of a wavelength difference between a wavelength band (61-66), the R. 415710 - 11 - the first multibandpass filter (21 -23) of an optical channel allows to pass through and corresponds to a wavelength band (71 -76) that the second multibandpass filter (31 - 33) of the same optical channel allows to pass through.
6. Optical analysis device according to one of claims 1 to 5, characterized in that it is configured to perform an amplification of the sample (40).
7. Optical analysis device according to one of claims 1 to 6, characterized in that the multibandpass filters (21-23, 31-33) are double bandpass filters.
8. Optical analysis device according to claim 7, characterized in that the wavelength bands (61-66) which pass through the first double bandpass filters (21-23) and the wavelength bands (71-76) assigned to them in an optical channel, which pass through the second double bandpass filters (31-33), are each numbered 1 to 2*f in ascending or decreasing wavelength ranges, wherein the first filter carrier (20) has a first double bandpass filter (21) for the wavelength bands (61, 66) 1 and 2*f and further first double bandpass filters (22, 23) for the wavelength bands (62-65) n and n+f-1, wherein 2 < n < f, and the second filter carrier (30) has second double bandpass filters (31-33) for the wavelength bands (71-76) n and n+f, wherein 1 < n < f is.
9. Method for operating an optical analysis device according to one of claims 1 to 8, wherein a sample (40) is arranged on the sample carrier (12), is excited to fluorescence by means of the light source (11) and light emitted by the sample (40) is detected by the optical sensor (13), wherein a fluorescence analysis of the sample is carried out in m*f optical channels.
10. Method according to claim 9, characterized in that the sample (40) is brought into contact with mf fluorophores.