Arrangement for operating a biosensor and arrangement for determining glucose content in blood - Patents.com

Abstract

The present invention relates to an arrangement for operating a biosensor (01) that emits a beam. The arrangement includes an excitation light source (03) that generates at least one excitation beam for the biosensor, a coupling fiber (04) into whose entrance face the excitation beam is coupled, an optical Y coupler (12) having an excitation arm (11) connected to the exit face of the coupling fiber (04), a detector arm (13) connected to an optical detector (21), and a sensor base (14) that is connectable to the biosensor (01). The excitation arm (11) has a conical shape. The optical axis of the excitation arm (11) surrounds the main optical axis of the detector arm (13) at an angle ranging from 5° to 70°. The diameter of the excitation arm (11) at the connection point (16) with the detector arm is less than two-thirds the diameter of the detector arm (13). The present invention also relates to an arrangement for determining glucose content, particularly in blood.

Description

[Technical Field]

[0001] The present invention relates to an optical fiber arrangement for operating a biosensor, which is particularly, but not exclusively, suitable for determining the glucose content in blood. The invention therefore also relates to an arrangement for determining the glucose content in blood. [Background technology]

[0002] Optical sensors are used, inter alia, to evaluate fluorescent light beams. In many cases, excitation radiation is provided by an optical arrangement, and the emitted beam is evaluated by a suitable fluorophore. The intensity of the emitted fluorescent light beam can then be a measure for the variable to be monitored.

[0003] For example, Patent Document 1 describes an arrangement for investigating an excitable sample using an electromagnetic beam. To separate the excitation beam from the emitted measurement beam, the arrangement includes a first dichroic beam splitter, which includes first and second prisms connected to each other at their base surfaces and a dichroic layer disposed between the base surfaces of the two prisms. A light source provides an electromagnetic beam suitable for exciting the sample, which is coupled into the entrance surface of the first prism. A portion of the radiation is reflected by the dichroic layer toward the sample, which is disposed behind the exit surface of the first prism. A detector is used to detect the electromagnetic measurement beam emitted by the sample, guided through the beam splitter, and exiting from there at the measurement surface. A disadvantage of such an arrangement is its high sensitivity and relatively large structure, which makes it impossible to use, for example, in everyday situations and by untrained personnel.

[0004] Non-Patent Document 1 describes an arrangement with a glucose-sensitive sensor, which is formed as a biosensor at the end of an optical fiber. To this end, one or more fluorescent substances are arranged in the fiber, which are excited by an excitation beam. The excitation beam is provided by an LED and coupled to the fiber via a lens. The intensity of the emitted fluorescent beam depends on the glucose content of the blood in the tissue in which the fiber can be implanted in the specific application. The emitted fluorescent beam is guided within the fiber to a detector and evaluated thereby. In principle, such a biosensor is suitable for quasi-continuous measurement of blood glucose content, so that a supply value can be provided, for example, to an insulin dosing unit in order to administer insulin to the patient as needed. However, providing the excitation beam and evaluating the fluorescent beam provided by the biosensor are technically difficult to implement in the smallest units, which would force the patient to carry a larger arrangement.

[0005] Patent Document 2 describes a glucose monitor that includes a light source, a sensor, and a processor. The light source emits excitation light that is directed toward a sample to induce fluorescence of glucose in the sample. The excitation light causes the sample to generate return light containing fluorescence generated by any glucose in the sample. The sensor monitors the return light and generates two signals representing the intensity of the light within two spectral wavelength bands. The first signal indicates the intensity of the return light having a wavelength within the first wavelength band. The second signal indicates the intensity of the light within the second wavelength band. The processor processes both electrical signals to determine the glucose concentration in the sample. Optical components include a fiber or waveguide for optical transmission, a dichroic filter for separating the excitation light from the return light, an aperture with a slit, and a prism.

[0006] Patent document 3 discloses a solution for in vivo measurement of the concentration of low-molecular-weight plasma constituents. A fluorescence-based glucose sensor is shown with a catheter measuring chamber, and the detector and light source devices are in optical communication with the chamber via optical fibers. The excitation light from the light source passes through a filter onto a mirror glass and is then focused toward the end of the optical fiber. In one embodiment, these components can be miniaturized by using an LED as the light source and a photodiode as the light detector, and by implanting the entire device inside the body.

[0007] Patent Document 4 shows an optical system for detecting fluorescence from a biological sample, in which the optical coupler used includes a fiber for communication with a fluorophore, a light-emitting diode, a number of filters, and a photodiode.

[0008] Patent Document 5 shows an optical fiber glucose sensor including an element having proximal and distal end regions, the proximal end region designed to couple with an optical device including an excitation light source and a detector, the distal end region being capable of being positioned within a blood vessel and including a hollow space and a reflective surface, the hollow space including an indicator system.

[0009] Patent Documents 6 and 7 disclose an optical Y coupler that is composed of perpendicular optical waveguides with polymer jackets and laterally merging optical waveguides with polymer jackets. The perpendicular optical waveguides extend linearly at the merging portion, and the laterally merging optical waveguides extend at an angle α that is smaller than the critical angle for total reflection in the perpendicular optical waveguides. The perpendicular optical waveguides have a diameter of 50 to 6000 μm.

[0010] US Pat. No. 5,699,239 shows a waveguide-based Y-coupler consisting of four individual subelements.

[0011] Patent Document 9 describes a coupling arrangement between a multimode light source and an optical fiber using an intermediate fiber formed as an optical multimode intermediate fiber. The intermediate fiber has a partial region with a cross section and a tapered partial region. A Y coupler is formed using the tapered intermediate fiber.

[0012] Patent Document 10 describes a glucose detection arrangement that includes a sensor, a light source, and a photodetector, which are connected to each other by an optical fiber, and further uses a Y coupler formed by splitting the optical fiber into two strands. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] German Patent No. 10 2015 101 847 B4 Specification [Patent Document 2] German Patent Application Publication No. 694 08 976 T2 [Patent Document 3] U.S. Patent No. 4,344,438 [Patent Document 4] International Publication No. 2014 / 116597 A1 [Patent Document 5] European Patent Application Publication No. 2 989 975 A1 [Patent Document 6] DE 43 22 734 A1 [Patent Document 7] DE 43 41 086 A1 [Patent Document 8] U.S. Patent No. 6,553,164 [Patent Document 9] German Patent Application Publication No. 694 14 139 T2 [Patent Document 10] US Patent Application Publication No. 2004 / 0072358 A1 [Non-patent literature]

[0014] [Non-Patent Document 1] Mueller AJ, Knuth M, Nikolaus KS, Krivanek R, Kuester F, Hasslacher C, “First clinical evaluation of a new percutaneous optical fiber glucose sensor for continuous glucose monitoring in diabetes” Journal of Diabetes Science and Technology 2013, 7(1):13-23. January 1, 2013 Summary of the Invention [Problem to be solved by the invention]

[0015] Derived from US Pat. No. 5,999,239, the problem of the present invention is to provide an improved arrangement for operating a biosensor. This arrangement should be capable of providing an excitation beam and of detecting the measurement signal generated by the sensor with high sensitivity. A compact, installable design, a more reliable mechanical connection to the biosensor, and high optical reliability should be achieved. Furthermore, it is also considered a problem to provide an improved arrangement for determining the glucose content, in particular in blood, which allows for mobile and quasi-continuous measurement of the glucose content. [Means for solving the problem]

[0016] This and other problems are solved by an arrangement for operating a biosensor according to the attached claim 1 or by an arrangement for determining glucose content according to claim 17.

[0017] The arrangement according to the invention for operating a biosensor comprises an excitation light source generating at least one excitation beam for the biosensor. The arrangement further comprises a coupling fiber, the excitation beam being coupled to an input face of the coupling fiber. An optical Y coupler is further provided, the Y coupler having an excitation arm connected to an output face of the coupling fiber, a detector arm connected to an optical detector, and a sensor base connectable to the biosensor. The detector arm and the sensor base preferably have a common main optical axis. The optical axis of the excitation arm extends at an angle of 5° to 70°, particularly 5° to 30°, relative to the main optical axis of the detector arm. The excitation arm has an elongated conical shape, and the diameter of the excitation arm at its point of entry into the detector arm is less than two-thirds, particularly less than half, and particularly preferably less than one-third of the diameter of the detector arm at its connection.

[0018] In particular, the excitation light source is formed by an LED chip, which emits an excitation beam of, for example, 595 nm. The excitation beam is adapted to the biosensor in terms of wavelength and optical power and can, for example, contain two wavelengths if these are desired for the respective excitation purpose. Preferably, the light-emitting surface of the LED chip is arranged at a distance of 0.1 to 10 times the diameter of the coupling fiber from the entrance surface of the coupling fiber.

[0019] According to a preferred embodiment, the excitation light source is a planar, diffusely emitting emitter. In particular, the emission occurs from a thin layer, as occurs in thin-film LEDs. Particularly preferably, the excitation light source is therefore formed by a thin-film LED.

[0020] The coupling fiber is preferably a PMMA fiber or a sapphire fiber, which has, for example, a spherical, aspherical, or planar entrance surface facing away from the pump light source. The coupling fiber has a diameter, which is constant over its length and is preferably in the range of 0.1 to 2 mm, more preferably 0.3 to 0.7 mm, and particularly preferably 0.5 mm, and a length that is preferably 7 to 13 times the distance between the pump light source and the entrance surface of the coupling fiber, for example 5 to 15 mm, and particularly preferably 10 mm. The entrance surface of the coupling fiber is separated from the pump light source by a distance of, in particular, about 0.8 to 1.2 mm, particularly preferably about 1 mm; within this distance, the pump beam travels, in particular, through air. This distance results in only "flat beams," i.e., beams that only have a small angle with respect to the central axis of the coupling fiber, being coupled into the coupling fiber. The exit surface of the pump light source corresponds, in particular, to 10 to 60% of the cross-sectional area of ​​the coupling fiber.

[0021] An advantageous embodiment is characterized in that the coupling fiber has no curvature in the axial longitudinal direction, i.e. its longitudinal axis extends linearly, for example the coupling fiber may be made of a rigid material or may be guided in a non-curved sleeve.

[0022] According to a preferred embodiment, the exit face of the coupling fiber is coupled to the excitation arm of the optical Y coupler via a cutoff filter. This filter can filter out wavelengths corresponding to the fluorescence wavelengths emitted by the biosensor from the excitation beam, so that these wavelengths can be more easily detected as measurement signals by the detector. The cutoff filter is formed, for example, as a carrier glass with an applied filter layer. The exit face of the coupling fiber can be glued to this carrier glass, or it can be glued directly to the filter layer.

[0023] A particularly preferred embodiment is characterized by a specially adapted beam guide that allows optimized use of the existing optical power. For this purpose, the aforementioned "flat beam" is coupled into the mentioned coupling fiber. By "flat beam" is meant a beam with a small angular deviation in the propagation direction. The use of such a beam, inter alia, also allows for the efficient use of cutoff filters, which cut out specific wavelengths from the excitation beam, which therefore no longer reduce the quality of the measurement result. It is required that the excitation beam impinges on the surface of the cutoff filter as perpendicularly as possible, which is achieved when the excitation beam propagates in this coupling fiber with the smallest possible angular deviation from the longitudinal axis of the coupling fiber and thus impinges on the surface normal of the cutoff filter with the smallest possible angular deviation from this surface normal. Preferably, the excitation beam propagates in the coupling fiber at an angle of less than 40°, particularly preferably less than 30°, and in particular less than 25°, relative to the surface normal of the cutoff filter or the core axis of the coupling fiber.

[0024] An advantageous embodiment of the arrangement is characterized in that the diameter of the excitation arm continuously decreases from its entrance face, which is optically coupled to the exit face of the coupling fiber, to the connection point with the detector arm (a so-called tapered fiber). The excitation arm thus has the shape of an elongated truncated cone. At the connection point, i.e., at the location where the excitation arm, detector arm, and sensor base of the Y coupler converge, the diameter of the coupling arm is therefore significantly smaller than at its entrance face. In particular, the diameter of the excitation arm decreases by more than half along its longitudinal extension. In particular, the excitation arm has a diameter in the range of 0.1 to 0.2 mm at the junction with the detector arm. The tapering of the excitation arm serves, inter alia, to form an optical valve that allows the excitation beam to be coupled to the sensor base while simultaneously minimizing unwanted leakage of the fluorescence beam returned by the biosensor into the excitation arm.

[0025] According to a preferred embodiment, a colored glass piece is located between the coated carrier glass connected to the output face of the coupling fiber and the input face of the pump arm, which supports the filtering effect of the cutoff filter. The colored glass piece is formed in the form of a waveguide and may also have a conical shape. The colored glass piece is a colored optical filter glass, for example, provided by Schott AG.

[0026] In particular, the Y coupler is manufactured from plastic, in particular PMMA or PC. For example, a 3D printing process or an injection molding process is suitable for this. The diameter of the detector arm and the sensor base is in particular constant, for example in the range of 0.4 to 0.6 mm, in particular 0.5 mm. The sensor base can advantageously have a longitudinal bend with an angle of approximately 90°, in order to allow the biosensor to be easily connected at the output surface of the sensor base when the biosensor is implanted in tissue essentially perpendicular to the patient's skin surface.

[0027] A practical embodiment has a further piece of coloured glass in the form of a waveguide, which is arranged between the detector and the exit face of the detector arm, and which on the other hand serves to support the filter. Furthermore, it is advantageous if a lens and a filter are arranged in front of the detector to collimate the fluorescence beam coming from the detector arm and to filter out any excitation beam that may still be present.

[0028] The detector may in particular be formed as a photodiode or a similar component. If several fluorescence wavelengths are to be detected, it is advantageous to combine the beam splitter with several photodetectors of different sensitivities.

[0029] According to the invention, the sensor base serves not only for the mechanical coupling to the sensor fiber but also for the beam deflection, in particular for this purpose the sensor base is provided with a toric surface.

[0030] An arrangement according to the invention for determining the glucose content, in particular in blood, comprises a biosensor as well as an arrangement for its operation according to one of the embodiments described herein.

[0031] Further advantages and details of the invention emerge from the following description of preferred embodiments with reference to the drawings. [Brief explanation of the drawings]

[0032] [Figure 1] FIG. 1 shows a schematic diagram of a first embodiment of an arrangement according to the invention for operating a biosensor. [Figure 2] FIG. 2 shows a schematic diagram of a second embodiment of an arrangement for operating a biosensor. [Figure 3] Figure 3 shows the optical beam paths within the sensor base for beam deflection and for coupling into and out of the sensor fiber with low optical loss. DETAILED DESCRIPTION OF THE INVENTION

[0033] 1 shows, in a simplified side view, an arrangement for operating a biosensor. The biosensor is here formed as a sensor fiber 01, which comprises glucose-sensitive fluorophores 02 immobilized at its free end. When excited with an excitation beam, these fluorophores emit fluorescence radiation, the intensity of which depends on the glucose concentration in the medium in which the end of the biosensor is located. The medium may in particular be blood.

[0034] The arrangement for operating the biosensor includes an LED chip 03, preferably a thin-film LED, as an excitation light source. The LED chip 03 emits an excitation beam that is introduced into the coupling fiber 04 at a flat angle. The angle between the excitation beam and the core of the coupling fiber is preferably less than 30°. To this end, in the illustrated embodiment, the LED 03 is positioned approximately 1 mm away from the input face of the coupling fiber 04. The input face of the coupling fiber can be designed as a freeform, spherical, aspherical, or flat surface. The coupling fiber 04 has, for example, a diameter of 0.5 mm and a length of 10 mm. The output face of the coupling fiber 04 is fixed to a carrier glass 07 using adhesive 06. The carrier glass 07 is provided with one or more filter layers 08 that act as cutoff filters to filter out the wavelengths of the fluorescence radiation emitted by the fluorescent material 02 from the excitation radiation. In the propagation direction of the pump beam, the carrier glass 07 is followed by a first piece of colored glass 09, which supports the effect of a cut-off filter. The first piece of colored glass 09 is designed in the form of a waveguide and is connected on the other side to a pump arm 11 of an optical Y coupler 12. The pump arm 11 and the first piece of colored glass 09 have a cross section that tapers in the radial direction. The diameter of the pump arm 11 at its end facing away from the coupling fiber 04 is therefore, for example, only 0.1-0.2 mm.

[0035] The Y coupler 12 also includes a detector arm 13 and a sensor base 14. At the connection section 16, the excitation arm 11 enters the material passing from the remaining detector arm 13 to the sensor base 14. At the connection section 16, the detector arm 13 and the excitation arm 11 enclose an angle ranging from 5° to 70°, preferably from 5° to 30°, and particularly preferably about 15°. The main optical axes of the detector arm 13 and the sensor base 14 extend coaxially in the illustrated embodiment. In modified implementations, the main optical axes of the detector arm and the sensor base may also extend at an angle relative to each other, for example, with an angular variation of 10° to 40°. At its end facing away from the connection section 16, the sensor base 14 is flexible or curved to allow connection to the sensor fiber 01. The detector arm 13 and the sensor base 14 have a diameter of, for example, 0.5 mm.

[0036] The excitation beam is guided from the LED chip 03 via the coupling fiber 04, the excitation arm 11 and the sensor base 14 into the sensor fiber 01, where it excites the fluorescent material 02. The fluorescence beam emitted thereby returns through the sensor fiber 01 to the sensor base 14 of the Y coupler 12 and then travels largely into the detector arm 13. A second piece of colored glass 17 is connected to the end of the detector arm 13 facing away from the connection part 16, said second piece of colored glass 17 being in the form of a waveguide. An optical lens 18 is provided to collimate the fluorescence radiation emerging from the exit surface of the second piece of colored glass 17, followed by a further filter 19 to pass the fluorescence beam to the subsequent detector 21.

[0037] 2 shows a modified embodiment of the arrangement for operating the biosensor, which for the time being largely corresponds to the configuration according to FIG. 1. One difference is that the detector is divided into two partial detectors 21a and 21b, which are used to detect different wavelengths of the fluorescence beam. For this purpose, after the filter 19 in the beam direction there is a beam splitter 22, which divides the fluorescence beam into two partial beams according to wavelength. The partial beams are then sent to the respective partial detectors 21a, 21b. A second piece of colored glass 17 supports the effect of the filter 19.

[0038] FIG. 3 exemplarily shows the optical beam paths in the excitation arm 11, the detector arm 13, the region of the connection part 16, and also in the sensor base 14. The sensor base 14 is used for beam deflection and coupling to and decoupling from the sensor fiber, while at the same time creating the possibility of a separation of several hundred micrometers between the sensor base and the sensor fiber, which greatly facilitates positioning. As can already be seen from FIGS. 1 and 2, the sensor base 14 is preferably designed curved or bent to allow easy connection to the sensor fiber 01 and to perform beam deflection. The entrance surface in the excitation arm 11 and the exit surface in the sensor base 14 thereby form an angle with each other of greater than 45°, preferably about 90°. The connection part 16 is particularly preferably designed optically funnel-shaped, as shown by the beam paths in FIG. 3.

[0039] The funnel-shaped configuration of the connecting part 16 also offers significant advantages for the optical return path, i.e., for the path of the fluorescence light guided from the sensor fiber 01 back to the detector 21. With the illustrated beam guide, light losses can be minimized up to the point where the excitation arm merges into the detector arm. The relatively low emission from the fluorescent material 02 can thereby be evaluated particularly well in the detector. Thus, a distance of several hundred μm can be achieved between the sensor base and the sensor fiber, which is a significant advantage for the implementation-related structure.

[0040] A lens 23 is preferably formed on the side of the sensor base 14 facing the sensor fiber 01, in particular integrated into the material of the sensor base. The lens 23 is arranged behind the toric surface in the direction of the excitation beam in order to focus the excitation beam onto the entrance surface of the sensor fiber 01. The lens may be formed as a spherical or aspherical lens and may optionally be anti-reflection treated.

[0041] Particularly preferably, the numerical aperture also provided behind the lens 23 of the sensor base 14 in the direction of the sensor fiber 01 is adapted so that it essentially corresponds to the numerical aperture of the sensor fiber.

[0042] According to a preferred embodiment, the excitation arm 11 widens in diameter in the region of the connecting portion 16, as clearly shown in the beam path in Fig. 1. This widening is preferably effected by a linear or non-linear increase in diameter in the direction towards the sensor base 14. The circumferential line of the resulting widening cone in the longitudinal cross section may therefore be formed arbitrarily.

[0043] In the region of the curvature of the sensor base, the deflection of the beam is preferably: This is done with a toric surface 24 which can be mathematically described as: JPEG0007741072000001.jpg15166. where: The first radius of the toric surface is related to the X axis (radius around the axis in the X direction) (R_around_X; C=1 / R_around_X), KK = conic constant, The Y coordinate is entered as y in the formula, yielding the Z coordinate if the toric surface had its origin at Y=0 and Z=0 and was not rotated 45° counterclockwise. The second radius of the toric surface is related to the Y axis when the toric surface is not rotated 45° counterclockwise (the radius around the axis in the Y direction).

[0044] The reflection is preferably performed as total internal reflection at the toric surface. For example, an additional reflective layer can also be provided in this area. This is useful if the refractive index of the material at the sensor base is too low to allow for total internal reflection. In this case, an additional reflective layer can be provided at the toric surface.

[0045] This configuration ensures that the excitation beam extends from the excitation arm 11 via the connecting part 16 and the expansion in the region of the toric surface 24 to the lens 23 in the material of the excitation arm. Only at the lens 23 does the transition to air or gas take place and then enters the sensor fiber 01. [Explanation of symbols]

[0046] 01 Sensor fiber 02 Fluorescent materials 03 LED chip / LED 04 Connective Fiber 05 -- 06 Adhesive 07 Carrier Glass 08 Filter layer 09 The first piece of colored glass 10 -- 11 Excitation arm 12 Y coupler 13 Detector arm 14 Sensor-based 15 -- 16 Connection part 17 Second Colored Glass Piece 18 Lenses 19 Filters 20 -- 21 Detector 22 Beam Splitter 23 Aspherical Lens 24 Toric Surface

Claims

1. 1. An arrangement for operating a biosensor (01) that emits a beam, comprising: an excitation light source (03) for generating at least one excitation beam for said biosensor; a coupling fiber (04) into whose entrance face said excitation beam is coupled; an optical detector (21); an optical Y coupler (12) having an excitation arm (11) connected to the output face of the coupling fiber (04), a detector arm (13) connected to the optical detector (21), and a sensor base (14) connectable to the biosensor (01); Including, The excitation arm (11) has a conical shape, the optical axis of the excitation arm (11) and the main optical axis of the detector arm (13) form an angle in the range of 5° to 70°, including a connection (16) between the detector arm (13) and the excitation arm (11); the diameter of the excitation arm (11) at the connection (16) with the detector arm (13) is less than two-thirds the diameter of the detector arm (13); The excitation arm (11) has a cross section tapering in the radial direction, the diameter of the excitation arm (11) continuously decreases from the entrance surface of the excitation arm (11) optically coupled to the exit surface of the coupling fiber (04) in the direction of the connection portion with the detector arm (13), and the excitation arm (11) has the shape of an elongated truncated cone; The coupling fiber (04) is formed with a linearly extending longitudinal axis. arrangement.

2. 2. The arrangement according to claim 1, wherein the diameter of the pump arm (11) at the connection portion (16) is less than half the size of its entrance face.

3. 3. The arrangement according to claim 1 or 2, characterized in that the detector arm (13) and the sensor base (14) have a common main optical axis.

4. 4. The arrangement according to claim 1, wherein the excitation light source is an LED chip (03) having an emitting surface spaced apart from the entrance surface of the coupling fiber (04), the space being 0.1 to 10 times the diameter of the coupling fiber (04).

5. 5. The arrangement of claim 4, wherein the coupling fiber (04) has a length that is 7 to 13 times the distance between the excitation light source (03) and the entrance face of the coupling fiber (04).

6. 5. The arrangement according to claim 4, wherein the entrance surface of the coupling fiber (04) is designed as a plane, a spherical, an aspherical or a free-form surface.

7. 7. The arrangement according to claim 1, wherein a cut-off filter (07, 08) is arranged between the exit surface of the coupling fiber (04) and the entrance surface of the excitation arm (11), the cut-off filter (07, 08) filtering out wavelengths of the beam that can be emitted from the biosensor (01) from the excitation beam.

8. 8. The arrangement of claim 7, wherein the cut-off filter is made of a carrier glass (07) having an optical filter layer (08) disposed thereon, and the exit face of the coupling fiber (04) is glued to the filter layer (08).

9. a lens (18) for collimating the beam emitted by the biosensor (01) is arranged between the exit surface of the detector arm (13) and the detector (21); an optical filter (19) is disposed between the lens (18) and the detector (21), the filter (19) blocking the incident component of the excitation beam; 9. The arrangement according to any one of claims 1 to 8, characterized in that

10. 10. The arrangement according to claim 1, wherein a piece of colored glass (17) in the form of a waveguide is arranged at the exit end of the detector arm (13).

11. 11. The arrangement of claim 1, wherein the sensor base (14) includes a curved section, in which the beam deflection occurs at an angle greater than 45°.

12. 12. The arrangement of claim 11, wherein the sensor base (14) is formed with a toric surface (24) for deflecting a beam.

13. 13. The arrangement according to any one of claims 1 to 12, configured to determine glucose content, comprising a biosensor (01, 02) implantable in tissue and emitting a beam when excited.

14. 14. The arrangement of claim 13, wherein the biosensor is formed as an optical fiber (01), the optical fiber (01) having a glucose-sensitive fluorescent substance (02) on its exit surface, the fluorescent substance (02) emitting a fluorescent beam having a fluorescent wavelength when excited by the excitation beam.

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