Measuring method for determining a protection factor, and protection factor evaluation system
Patent Information
- Application Number
- EP2023809510
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-11-21
- Filing Date
- 2023-11-16
- Publication Date
- 2025-10-01
AI Technical Summary
Current methods for determining the Sun Protection Factor (SPF) are harmful to test subjects, as they induce erythema through UV radiation, and lack reliable in vitro methods that replace human skin with synthetic substrates, leading to high costs and complex, interferable equipment.
A method using spectroscopic measurements with a beam source emitting radiation between 280 nm and 2000 nm, detecting remitted radiation, and evaluating the SPF using in silico transmission spectrum data, which reduces skin stress and provides high-quality analysis results at lower costs, utilizing a compact SPF evaluation system with a beam source, detector unit, and control unit.
This method effectively determines the SPF with reduced radiation burden on human skin, providing accurate and cost-effective analysis, and is more compact and less expensive than existing systems, minimizing interference and improving measurement precision.
Smart Images
Figure 1.1
Abstract
Description
[0001] MEASURING METHOD FOR DETERMINING A PROTECTION FACTOR AND PROTECTION FACTOR EVALUATION SYSTEM
[0002] The invention relates to a method for determining a protection factor with the method steps of emitting radiation from a radiation source, wherein the emitted radiation comprises light with an irradiation wavelength between 280 nm and 2000 nm, irradiating a measuring body with the emitted radiation, detecting the radiation remitted by the irradiated measuring body with a detection wavelength, evaluating the protection factor of a protective agent with an evaluation wavelength from the remitted radiation and a transmission spectrum, wherein the data of a transmission spectrum are used for evaluating the protection factor of the protective agent, wherein the evaluation wavelength is different from the wavelength range of the irradiation wavelength and / or the detection wavelength, and wherein the data of the transmission spectrum are in silico data.Furthermore, the invention relates to an SPF evaluation system for investigating the protection factor of protective devices, which system has the following components: a measuring device with a radiation source device, wherein the radiation source device has a radiation source, a detector unit, a control unit for controlling the measuring device and an evaluation unit.
[0003] State of the art
[0004] Protection: The methods currently approved by the European Union (EU) and the American Food and Drug Administration (FDA) for determining SPF (Sun Protect Factor) are all harmful to the test subjects by causing erythema, a light-induced inflammatory reaction of the skin (COLI PA -15 European Cosmetic, Toiletry and Perfumery Association: Colipa SPF Test Method 94 / 289, 1994; ISO Standards 24442, 24443, 24444). Therefore, both the FDA and the EU have repeatedly pointed out that future research activities must focus on new methods for characterizing the protective efficacy of sunscreen products to avoid long-term effects for the test subjects (European Commission, 20 Standardization Mandate Assigned To CEN Concerning Methods For Testing Efficacy Of Sunscreen Products, M / 389 EN, Brussels, 12 July 2006).
[0005] This invention is intended to accomplish this task. Existing methods are defined in various sources:
[0006] Procedures defined in standards and regulations: a. ISO 24444 defines a method for the in vivo determination of SPF. The method is based on the induction of erythema on the skin of volunteers by radiation in the UVB range. Therefore, the method is harmful to the volunteer. b. ISO 24443 defines an in vitro method for the determination of the UVA protection factor (IIVAPF). The protectant is applied to a plastic plate so that a transmission spectrum of the protectant can be measured. Due to uncontrollable fluctuations in the procedure, the transmission spectrum is adjusted to the result of the erythema test according to ISO 24444 by scaling and is therefore dependent on the way the test is carried out. The plastic plate used has a roughened surface and is an unrealistic skin model. c.ISO 24442 defines an in vivo method in which the UVA protection factor is determined using the minimum UVA dose required to produce irreversible pigmentation (suntan) of the skin. This method also requires a change in the subject's skin.
[0007] Patented processes:
[0008] DE 198 28 497 A1 describes a method in which, as in ISO 24444, erythema is induced in volunteers by UV irradiation of the skin. Unlike ISO 24444, these erythemas are detected by reflectance spectroscopy. This method is therefore also harmful. The optical effect (protection) of the protective agent is not determined by direct optical measurements, but rather by a biological reaction of the body.
[0009] DE 10 2004 020 644 A1 describes a method in which the generation of radicals by UV exposure is quantitatively measured in vivo using electron paramagnetic resonance (ESR). Here, too, the optical effect of the protective agent is only indirectly measured. Furthermore, measuring ESR is technically complex and requires relatively large, stationary devices (tabletop devices). They are also sensitive to interference from high-frequency radiation or rapid, temporary magnetic field changes, such as those caused by electrical switching processes.
[0010] To determine the label SPF of topically applied protective products in vivo, test methods such as ISO 24444, the FDA Guideline, or the Australian Standard are used worldwide. All of these methods are based on inducing an erythemal skin reaction by irradiating the skin with UV light. This is necessary to determine the minimum erythemal dose of untreated (MEDu) and product-treated skin (MEDp). Reliable in vitro methods that replace human skin with synthetic substrates are not available for SPF determination.
[0011] Monochromatic devices are known, which use conventional xenon lamps and are therefore expensive to purchase and operate. Built-in monochromators measure different wavelengths one after the other, which is disadvantageous when the subjects are moving. Polychromatic devices also use xenon lamps. The in vivo measured value is weighted using a filter so that it matches the in vivo UVA PF. Multi-LED devices for testing institutes represent another option, but these are significantly larger and more expensive due to the spectroscopic detection.
[0012] It is therefore an object of the invention to provide a method for determining a protection factor that reduces the exposure to radiation on human skin, provides high-quality analytical results, and is quick and easy to perform. It is also an object of the invention to provide an SPF evaluation system for investigating the protection factor of protective agents that provides high-quality analytical results, reduces the exposure to radiation on human skin, and is cost-effective to manufacture and operate.
[0013] This object is achieved by means of the inventive method for determining a protection factor. Advantageous embodiments of the invention are set forth in the following subclaims.
[0014] The method according to the invention for determining a protection factor comprising a spectroscopic measurement has four method steps: In the first method step, radiation is emitted from a radiation source, wherein the emitted radiation comprises light with an irradiation wavelength between 280 nm and 2000 nm, preferably 280 to 800 nm, particularly preferably the range from 280 to 500 nm. In the context of this document, a radiation source is a technical device for generating electromagnetic radiation. A radiation source is therefore not an optical element for guiding, deflecting, or changing the intensity and / or wavelength of the electromagnetic radiation. A radiation source is therefore not, for example, a light guide, grating, prism, or filter. The radiation source generates electromagnetic radiation with an irradiation wavelength between the blue spectral range (from approximately 400 nm to 500 nm wavelength) and the UV range (280 nm to 400 nm).
[0015] The wavelength ranges are defined as follows:
[0016] - < 320 nm (UVB) with < 0.1% of the total UV intensity,
[0017] - 320 nm to 340 nm (UVA II) 8% to 20% of the total UVA intensity
[0018] - 340 nm to 400 nm (UVA I) 80% to 92% of the total UVA intensity
[0019] - 400 nm to 500 nm, blue light
[0020] The irradiation wavelength preferably covers a wavelength range between 280 nm and 500 nm. In the second method step, a measuring body is irradiated with the emitted radiation. In the case of an in vivo measurement, the measuring body is human skin covered with the protective agent to be tested; in the case of an in vitro measurement, it is a standardized test body covered with the protective agent to be tested.
[0021] In the third process step, the remitted radiation from the irradiated measuring body is detected at a detection wavelength. The ratio of the intensities of the remitted radiation to the radiation coupled into the measuring body is a measure of the protective capability of the protective agent. Like the irradiation wavelength, the detection wavelength preferably covers a wavelength range, with the wavelength range of the detection wavelength preferably lying within the range of the irradiation wavelength or encompassing the entire range of the irradiation wavelength. The spectroscopic measurement therefore includes, in particular, the acquisition of the remitted spectrum l(A) (diffuse backscattering).
[0022] In the fourth step, the protection factor of a protective agent is evaluated using an evaluation wavelength from the remitted radiation and a transmission spectrum. The data from a transmission spectrum is used to evaluate the protection factor of the protective agent. A transmission spectrum is determined based on the UV transmittance of protective films in vitro. The substrates to which the protective films are applied only approximately replicate the inhomogeneous surface structure of human skin, such as polymethyl methacrylate (PMMA) sheets with a rough surface according to ISO 24443. The transmission spectrum data includes intensity versus wavelength, preferably in a digitized format.
[0023] The evaluation wavelength is the wavelength for which the protection factor is determined. The evaluation wavelength is different from the wavelength range of the irradiation wavelength and / or the detection wavelength. The evaluation wavelength, like the irradiation wavelength and the detection wavelength, is preferably a wavelength range, wherein the wavelength range of the evaluation wavelength comprises at least the wavelength range of the irradiation wavelength and / or the detection wavelength.
[0024] Advantageously, the transmission spectrum data are in silico data. The transmission spectrum data are therefore neither determined in vivo on a test subject nor in vitro according to ISO 24443, but rather estimated or determined mathematically. If the properties of the filter substances of a protective agent are known, the transmission can be calculated and simulated. Based on the simulated transmission, the sun protection factor and all parameters that characterize the protection factor can be calculated.
[0025] The protection factor (SPF) is a scientific measure that indicates how much lower the risk of skin damage is due to the use of a protectant. This factor focuses on the time it takes for UVB rays to penetrate a protectant and cause the skin to redden (minimal erythema, MED) compared to the time it takes to do so in the absence of a protectant. The dose of solar radiation required to cause skin reddening is divided by the dose required to cause reddening without a protectant. This calculation is based on the application of 2 milligrams of protectant per square centimeter of skin surface. Currently, the SPF of protectants is determined via in vivo irradiation using a sun simulator (ISO 24444:2010 "Cosmetics - Sun protection test methods - In vivo determination of the sun protection factor (SPF)"), which represents the current state of the art.The basis for current testing of protective agents is that subjects are irradiated before and after the application of protective agents.
[0026] The advantage of the method according to the invention lies in the fact that the in silico data do not represent a standard and can currently only be used for estimation. However, the deviation of the estimate from the actual data is significantly improved with the inventive approach.
[0027] In a further development of the invention, the wavelength range of the transmission spectrum comprises the evaluation wavelength. The evaluation of the protection factor of the protection agent is carried out from the in vivo remitted radiation and the in silico transmission spectrum. Due to its high absorption properties, human skin does not emit sufficient UVB radiation to measure the absorption spectrum of the applied product in the UVB range. It is therefore necessary to separately record the absorption spectrum of the test material in the UVB part of the spectrum (280-320 nm) using a different technique. The approach applied in this document uses the in vivo evaluation of the absolute UVA absorption spectrum, as measured with an in vivo measurement, with the use of a calculated in silico transmission spectrum to determine the protection factor of the protection agent for a user.The evaluation and hybridization of an in vivo remission spectrum with an in silico transmission spectrum is carried out to obtain a complete UV spectrum, so that the protection factors are calculated according to the formulas of the applicable standard (ISO 24443). For this purpose, the wavelength range of the transmission spectrum includes the evaluation wavelength, which preferably covers the range from 280 nm to 500 nm.
[0028] In a further embodiment of the invention, the evaluation wavelength comprises the wavelength range from 280 nm to 2000 nm, preferably the wavelength range from 280 nm to 800 nm, or particularly preferably the wavelength range from 280 nm to 500 nm. In a further development, the evaluation wavelength comprises a wavelength range from 400 nm to 500 nm, and preferably from 400 nm to 450 nm. Preferably, the wavelength range of blue light bordering the UVA range (up to 400 nm) is evaluated. To determine the protective ability of the protection agent in the UVB wavelength range (< 320 nm), this wavelength range can also optionally be evaluated.
[0029] In a further embodiment of the invention, the evaluation of the protective ability of the protective agent for light in a wavelength range from 400 nm to 500 nm is carried out in a separate process from the evaluation of the protective ability of the protective agent for light in a wavelength range from 280 nm to 400 nm. Due to its high absorption properties, human skin does not emit sufficient UVB radiation to measure the absorption spectrum of the applied product in the UVB range. It is therefore necessary to separately measure the absorption spectrum of the test material in the UVB part of the spectrum (280-320 nm) using a different technique. For this purpose, the in vivo reflectance spectrum in the wavelength range from 320 nm to 400 nm is recorded, the wavelength range from 280 nm to 320 nm, and the wavelength range from 400 nm to 500 nm are recorded using an in silico transmission spectrum.
[0030] In a further embodiment of the invention, the evaluation of the protective ability of the protective agent for light in a wavelength range from 400 nm to 500 nm is carried out using a different method than the evaluation of the protective ability of the protective agent for light in a wavelength range from 280 nm to 400 nm. Due to its high absorption properties, human skin does not emit sufficient UVB radiation to measure the absorption spectrum of the applied product in the UVB range. It is therefore necessary to separately record the absorption spectrum of the test material in the UVB part of the spectrum (280-320 nm) using a different technique. For this purpose, the in vivo reflectance spectrum in the wavelength range from 320 nm to 400 nm is recorded, the wavelength range from 280 nm to 320 nm, and the wavelength range from 400 nm to 500 nm are recorded using an in silico transmission spectrum.
[0031] In a further embodiment of the invention, the wavelength range of the irradiation wavelength or the wavelength range of the detection wavelength is smaller than the wavelength range of the evaluation wavelength. The wavelength ranges of the irradiation wavelength and the detection wavelength are preferably identical within a wavelength range of a maximum of 320 nm to 400 nm. The wavelength range of the evaluation wavelength covers a maximum range of 280 nm to 500 nm.
[0032] In a further embodiment of the invention, the wavelength range of the irradiation wavelength or the wavelength range of the detection wavelength in the wavelength range of the evaluation wavelength is smaller than the wavelength range of the evaluation wavelength. The wavelength ranges of the irradiation wavelength and the detection wavelength are preferably equal in a wavelength range from 320 nm to 400 nm, with the wavelength ranges of the irradiation wavelength and the detection wavelength being smaller than the aforementioned wavelength range of 320 nm to 400 nm. In the wavelength range of the evaluation wavelength (maximum 280 nm to 500 nm), the wavelength range of the irradiation wavelength or the wavelength range of the detection wavelength in the wavelength range of the evaluation wavelength is then smaller than the wavelength range of the evaluation wavelength.
[0033] In a further development of the invention, the wavelength range of the irradiation wavelength and / or the wavelength range of the detection wavelength is less than 100 nm, preferably less than 50 nm, and particularly preferably less than 25 nm. Therefore, only one beam source is required to emit electromagnetic radiation, which has a narrow wavelength range of the irradiation wavelength. Similarly, a detector capable of capturing the narrow wavelength range of the detection wavelength is required to record the remission spectrum. The beam source and detector can therefore be designed to be cost-effective in both manufacture and operation.
[0034] In a further embodiment of the invention, the irradiation wavelength and / or the detection wavelength only includes light with wavelengths outside the wavelength range of 400 nm to 450 nm. For in vivo measurement, the UVA wavelength range (320 nm - 400 nm) is coupled into the measuring body.
[0035] In a further development of the invention, the irradiation wavelength and / or the detection wavelength only includes light with wavelengths outside the wavelength range of 400 nm to 500 nm. In particular, the UVA and UVB wavelength range is irradiated. The greatest risk to human skin lies in this wavelength range, so determining the protective ability of a protective agent is particularly important.
[0036] In a further embodiment of the invention, the evaluation wavelength includes wavelengths outside the wavelength range of 400 nm to 500 nm. In particular, the UVA and UVB wavelength range is evaluated. This wavelength range poses the greatest risk to human skin, so determining the protective ability of a protective agent is particularly important. In a further embodiment of the invention, the evaluation wavelength includes wavelengths A with A < 400 nm. To capture an in vivo measurement, the UVA wavelength range (320 nm - 400 nm) is evaluated in particular.
[0037] In a further embodiment of the invention, the evaluation wavelength comprises wavelengths A with 320 nm < A < 400 nm. To capture an in vivo measurement to determine the protective ability of the protective agent, the UVA wavelength range (320 nm - 400 nm) is evaluated in particular. To determine the protective ability of the protective agent in the UVB wavelength range (< 320 nm), this wavelength range can also be optionally evaluated.
[0038] In a further embodiment, radiation is emitted from a single beam source, with the emitted radiation from the single beam source comprising light in a wavelength range between 280 nm and 500 nm. A beam source, in the context of this document, is a technical device for generating electromagnetic radiation. A beam source is therefore not an optical element for guiding, deflecting, or modifying the intensity and / or wavelength of the electromagnetic radiation. A beam source is therefore not, for example, a light guide, grating, prism, or filter. The beam source generates electromagnetic radiation in a wavelength range within the blue spectral range (from approximately 400 nm to 500 nm wavelength) and the UV range (280 nm to 400 nm).In a further development of the invention, the emitted radiation of the one beam source comprises only a partial range of the wavelength range between 280 nm and 500 nm, in a preferred embodiment the wavelength range of the radiation emitted by the one beam source is less than 50 nm wide and in a particularly preferred embodiment the one beam source is a single LED.
[0039] In a further development of the invention, the individual beam sources can be controlled. This enables targeted control of the beam source and targeted adaptation of the overall spectrum to different applications. By appropriately selecting the intensity of the beam source, a radiation dose can also be achieved, either in the form of an individual dose (e.g., 0.1 MED) or an adjustable limit value. This minimizes the radiation dose for a test subject. In a further aspect of the invention, the beam source is controlled by a beam source control. The beam source control specifically controls the beam source and enables targeted adaptation of the spectrum generated by the beam source, e.g., by controlling the wavelength range and the intensity of the electromagnetic radiation generated by the beam source.
[0040] In a further embodiment of the invention, the wavelength, exposure time, and / or intensity of the individual beam sources are controlled by controlling the beam source. This enables targeted control of the beam source for in vivo measurements on the one hand and in vitro measurements on the other. By appropriately selecting the intensity of the beam source and the exposure time of the measuring body, a radiation dose is also selected, either in the form of an individual dose (e.g., 0.1 MED) or an adjustable limit. This minimizes the radiation dose for a subject.
[0041] In a further aspect of the invention, the transmission spectrum is adjusted using the detected remitted radiation. The adjustment is carried out in such a way that a hybrid transmission spectrum T hyb is determined according to: with Ti n ViVo as transmission spectrum determined from the spectrum of the detected remitted radiation determined by in vivo measurement and T in S iiico the calculated transmission spectrum
[0042] In a further embodiment of the invention, the radiation is emitted in vivo on human skin according to ISO 24442. ISO 24442 defines an in vivo method in which the UVA protection factor is determined using the minimum UVA dose required to produce irreversible pigmentation (suntan) of the skin. In a further advantageous embodiment of the invention, the protective ability of the protective agent is evaluated using two measurements. The protective ability of the protective agent is determined by the time it takes for UVB rays to penetrate a protective agent and cause the skin to redden (minimal erythema, MED) in a second measurement, compared to the time this takes when no protective agent is present. In a first measurement, the dose of solar radiation required to cause skin reddening is divided by the dose required to cause reddening without a protective agent.
[0043] In a further development of the invention, a first measurement is taken before the protective agent is applied to the measuring body. This first measurement records the time at which minimal erythema (MED) appears on the subject's untreated skin.
[0044] In a further aspect of the invention, a second measurement is taken after the protective agent has been applied to the measuring body. This second measurement records the time at which minimal erythema (MED) appears on the subject's skin treated with the protective agent.
[0045] In a further embodiment of the invention, the beam source generates polychromatic radiation, whereby the generated polychromatic radiation is radiated unfiltered onto the measuring body. The beam source generates radiation in a maximum wavelength range of 280 nm to 500 nm (UVB to blue light). The generated polychromatic radiation is not altered by optical elements (filters, monochromators) in the generated wavelength range from the generation of the polychromatic radiation until it impinges on a measuring body. This achieves a maximum intensity of the generated radiation, a likewise maximum intensity of the remitted or transmitted radiation, and consequently a high signal-to-noise ratio.
[0046] In a further development of the invention, the measurement of the remission spectrum and / or remission value is carried out exclusively in vivo. In a first measurement, the remission spectrum and / or the remission value of human skin without protective agents is recorded, and in a second measurement, the remission spectrum and / or the remission value of human skin without protective agents is recorded.
[0047] The object is further achieved with the SPF evaluation system for examining the protection factor of protective agents according to claim 25. Further advantageous embodiments of the invention are also set out in the subclaims.
[0048] The SPF evaluation system according to the invention for examining the protection factor of protective devices comprises a measuring device, wherein the measuring device comprises a radiation source device. The radiation source device comprises a radiation source, a detector unit, a control unit for controlling the measuring device, and an evaluation unit.
[0049] The measuring device is designed to introduce electromagnetic radiation into a measuring body, preferably human skin, using a radiation source. A radiation source is a technical device for generating electromagnetic radiation.
[0050] Furthermore, the measuring device is suitable for detecting the remitted electromagnetic radiation. The measuring device can be controlled by the control unit, and the radiation detected by the detector unit can be processed by the control unit. The detection window and the resolution of the spectrometer are determined by the control unit, and the detected signals are stored, processed (e.g., amplified), and displayed and evaluated by the evaluation unit.
[0051] In one development of the invention, the SPF evaluation system is suitable for examining the protective ability of protective agents for protection against light in an evaluation wavelength range. The evaluation wavelength range is the wavelength range for which the protection factor is determined. The evaluation wavelength range is different from the wavelength range of the irradiation wavelength and / or the detection wavelength, wherein the wavelength range of the evaluation wavelength range comprises at least the wavelength range of the irradiation wavelength and the detection wavelength. In one advantageous embodiment of the invention, the SPF evaluation system has precisely one measuring device. In one development of the invention, the precisely one measuring device has precisely one beam source device. In a further aspect of the invention, the precisely one beam source device has precisely one beam source.According to the invention, the measurement and detection of electromagnetic radiation is not carried out using a combined spectrum generated by different radiation sources, but rather with just one measuring device, one radiation source device, and one radiation source, with the radiation source preferably being an LED. This makes the SPF evaluation system according to the invention significantly more compact and cost-effective than known systems.
[0052] In a further embodiment of the invention, the precisely one beam source device can be controlled by precisely one control unit for controlling the measuring device. The control unit can control the range of the irradiation wavelength and the intensity of the radiation emitted by the beam source device.
[0053] In a further embodiment of the invention, the precisely one measuring device has precisely one detector unit. In a further development of the invention, the precisely one detector unit has precisely one detector. In a further embodiment of the invention, the precisely one detector unit can be controlled by precisely one control unit for controlling the measuring device. The detector unit comprises, for example, a monochromator, filter, photomultiplier, spectrometer and / or a photodiode. All of these devices are suitable for detecting electromagnetic radiation and recording its intensity as a function of the wavelength. The detection of an in vivo measurement is preferably carried out using a photodiode. As a result, the SPF evaluation system according to the invention is significantly more compact and cost-effective than known systems.The detection window and the resolution of the spectrometer are determined by the control unit, and the detected signals are stored, processed (e.g., amplified), and displayed by the control unit. In a further embodiment of the invention, the precisely one beam source device is suitable for emitting light with an irradiation wavelength, wherein the wavelength range of the irradiation wavelength is smaller than the wavelength range of the evaluation wavelength. The precisely one beam source device generates electromagnetic radiation with an irradiation wavelength between the blue spectral range (from approximately 400 nm to 500 nm wavelength) and the UV range (280 nm to 400 nm). The evaluation wavelength is the wavelength for which the protection factor is determined. The evaluation wavelength is different from the wavelength range of the irradiation wavelength.The evaluation wavelength is like the irradiation wavelength and preferably a wavelength range, wherein the wavelength range of the evaluation wavelength comprises at least the wavelength range of the irradiation wavelength.
[0054] In a further embodiment of the invention, the precisely one detector unit is suitable for detecting light with a detection wavelength, wherein the wavelength range of the detection wavelength is smaller than the wavelength range of the evaluation wavelength. The detection wavelength, like the irradiation wavelength, preferably comprises a wavelength range, wherein the wavelength range of the detection wavelength preferably lies within the range of the irradiation wavelength or comprises the range of the irradiation wavelength.
[0055] In a further aspect of the invention, the wavelength range of the irradiation wavelength or the wavelength range of the detection wavelength in the wavelength range of the evaluation wavelength is smaller than the wavelength range of the evaluation wavelength. For recording an in vivo measurement, the wavelength range of the irradiation wavelength includes, in particular, the UVA wavelength range (320 nm - 400 nm) that is irradiated into the measuring body. The wavelength range of the detection wavelength includes, at most, the wavelength range of the irradiation wavelength (320 nm - 400 nm).
[0056] The wavelength range of the evaluation wavelength covers a larger range; in particular, the wavelength range from 280 nm to 500 nm (UVB to blue light) is evaluated. In a further development of the invention, the wavelength range of the irradiation wavelength and / or the wavelength range of the detection wavelength is less than 100 nm, preferably less than 50 nm, and particularly preferably less than 25 nm. Therefore, only one beam source is required to emit electromagnetic radiation, which has a narrow wavelength range of the irradiation wavelength. Similarly, a detector capable of capturing the narrow wavelength range of the detection wavelength is required to record the remission spectrum. The beam source and detector can therefore be designed to be cost-effective in both manufacture and operation.
[0057] In a further embodiment of the invention, the SPF evaluation system has exactly one control unit. The control unit is typically a PC or notebook computer with a suitable computer program. The SPF evaluation system can be controlled by means of the control unit, and the radiation detected by the detector unit can also be processed by the control unit. The wavelength range of the detection wavelength and the resolution of the detector unit are determined by the control device, and the detected signals are stored, processed (e.g., amplified), and displayed. This enables targeted control of the radiation source and targeted adaptation of the overall spectrum to different applications. By appropriately selecting the intensity of the radiation source, a radiation dose is also achieved, either in the form of an individual dose (e.g., 0.1 MED) or an adjustable limit value. This minimizes the radiation dose for a test subject.
[0058] In an advantageous embodiment of the invention, the SPF evaluation system is suitable for investigating the protective ability of protective agents for light protection and / or evaluating the protection factor of a protective agent using measurement data exclusively from the measurement data device. The evaluation is carried out using the inventive method for determining a protection factor according to claims 1 to 24. The SPF evaluation system detects the remitted radiation of the irradiated measuring body (human skin with and without a protective agent). The evaluation of the protective agent is carried out using the data of the remission spectrum and incorporating the data of a transmission spectrum, wherein, according to the invention, the data of the transmission spectrum are in silico data.
[0059] Embodiments of the method according to the invention for determining a protection factor comprising a spectroscopic measurement and of the SPF evaluation system according to the invention for examining the protection factor of protective agents are shown in a simplified schematic form in the drawings and are explained in more detail in the following description.
[0060] They show:
[0061] Fig. 1 : SPF evaluation system, evaluation unit arranged outside the measuring device
[0062] Fig. 2: SPF evaluation system, control unit and evaluation unit arranged in one device
[0063] Fig. 3: SPF evaluation system, beam source control unit controlled by control unit
[0064] Fig. 4: SPF evaluation system, control unit and evaluation unit arranged separately in one device
[0065] Fig. 5: SPF evaluation system, control unit, beam source control unit and
[0066] Evaluation unit arranged in one device
[0067] Fig. 6: Procedure for performing a spectroscopic measurement (in vivo) for
[0068] Recording a reflection spectrum
[0069] Fig. 7: Combined method for determining a protection factor with a
[0070] Measurement to acquire a reflection spectrum and in silico data in the form of a transmission spectrum
[0071] Fig. 1 schematically shows an embodiment of the SPF evaluation system 1 according to the invention for performing an in vivo measurement. The SPF evaluation system 1 comprises the measuring device 6 with a radiation source device 12. The radiation source device 12 comprises a radiation source 12.1 and optical elements intended and / or suitable for conditioning and / or redirecting the radiation generated by the radiation source 12.1, e.g., optical fibers, filters, monochromators, mirrors, and / or other optical elements.
[0072] By means of a light guide 4.1, the light emitted by the beam source device 12, with an irradiation wavelength between 280 nm and 500 nm, is introduced into the measuring body 3 via the probe head 5. The light reflected by the measuring body 3 reaches the detector unit 13 via another light guide 4.2. The detector unit 13 has a monochromator, filter, photomultiplier, spectrometer, and / or a photodiode. In this and all subsequent embodiments, the detector unit 13 has a photodiode. The detector unit 13 and the beam source device 12 are connected via data lines 23, 24 to a control unit 2, which in turn is connected to the evaluation unit 10 via another data line 25. The control unit 2 is typically a PC or notebook computer with a suitable computer program. The control unit 2 and the detector unit 13 are also connected to each other via a data line 22.
[0073] A further embodiment of the SPF evaluation system 1 according to the invention is shown in Fig. 2. The SPF evaluation system 1 also has the measuring device 6 with a beam source device 12. By means of the optical fiber 4.1, the light emitted by the beam source device 12 is introduced via the probe head 5 into the measuring body 3, and the light reflected by the measuring body 3 reaches the detector unit 13 via a further optical fiber 4.2. The detector unit 13 and the beam source device 12 are connected via data lines 23, 24 to the control unit 2, which in this embodiment forms a structural unit with the evaluation unit 10.
[0074] A further embodiment of the SPF evaluation system 1 according to the invention, also for carrying out an in vivo measurement, is shown in Fig. 3. The SPF evaluation system 1 has the measuring device 6 with a beam source device 12. By means of the light guide 4.1, the light emitted by the beam source device 12 is introduced via the probe head 5 into the measuring body 3, and the light reflected by the measuring body 3 reaches the detector unit 13 via a further light guide 4.2. The detector unit 13 and the beam source device 12 are connected to a beam source controller 11 via data lines 23, 24. The beam source controller 11 and the detector unit 13 are each connected to the control unit 2 via the data line 21, the evaluation unit 10 is arranged separately and is also connected to the control unit 2 and the beam source controller 11 via the data line 21.
[0075] A further embodiment of the SPF evaluation system 1 according to the invention is shown in Fig. 4. The SPF evaluation system 1 also has the beam source device 12. By means of the optical fiber 4.1, the light emitted by the beam source device 12 is introduced via the probe head 5 into the measuring body 3, and the light reflected by the measuring body 3 reaches the detector unit 13 via a further optical fiber 4.2. The detector unit 13 and the beam source device 12 are connected to a beam source control 11 via data lines 23, 24. In this exemplary embodiment, the control unit 2 is arranged as a structural unit with the evaluation unit, remote from the SPF evaluation system 1 and connected to it via the interface 16. The connection can be wired or wireless, e.g., via an IP connection, Bluetooth, etc.Interface 16 and detector unit 13 on the one hand and interface 16 and beam source control 11 are connected to each other via the data lines 21, 22.
[0076] A preferred embodiment of the SPF evaluation system 1 according to the invention, also for performing an in vivo measurement, is shown in Fig. 5. The SPF evaluation system 1 corresponds to the SPF evaluation system 1 presented in the first embodiment (see Fig. 1), except that the control unit 2 is arranged in the measuring device 6 as a unit with the beam source controller 11 and the evaluation unit 10. The SPF evaluation system 1 has precisely one measuring device 6 with precisely one beam source 12.1 and precisely one detector unit 13. The beam source 12.1 is an LED, and the detector unit 13 is a photodiode. The precisely one control unit 2, as a unit with precisely one evaluation unit 10 and precisely one beam source controller 11, controls precisely one beam source 12.1 via the data line 23 and receives data from precisely one detector unit 13 via the data line 24.This SPF evaluation system 1 presented here has a particularly compact design, requires only a small number of components, and is therefore inexpensive to manufacture and use. Fig. 6 shows an exemplary embodiment of an implementation of the method 100 of an in vivo measurement for detecting the remission spectrum using the SPF evaluation system 1 according to the invention from the preceding exemplary embodiments (see Figs. 1 to 5). The measurement is carried out in vivo according to ISO 24442 or 24444. The method 100 of a measurement requires the recording of a remission spectrum of the skin of subject 3 untreated with a protective agent and of the skin treated with a protective agent.
[0077] For this purpose, the probe head 5 is applied to the untreated skin of the test subject 3, i.e., the protective agent to be tested is not applied to the skin of the test subject 3. For this purpose, a location on the inside of the forearm or the back of a test subject 3 is typically selected. The first measurement 110 is then performed by the beam source control 11 controlling the LED 12.1 such that the light generated by the LED 12.1 (see Fig. 4) is directed through the light guide 4.1 onto the skin of the test subject 3.
[0078] The generated electromagnetic radiation has an irradiation wavelength range with a FWHM of up to 20 nm, wherein the generated electromagnetic radiation lies in the wavelength range from 330 nm to 350 nm. The wavelength range of the detection wavelength, in which the detector unit 13 detects the remitted radiation by means of the optical fiber 4.2, also has a range of, for example, 20 nm in the range from 330 nm to 350 nm. Furthermore, the irradiation wavelength range and / or the detection wavelength range is less than 100 nm, preferably less than 50 nm, and particularly preferably less than 25 nm.
[0079] For some applications, FWHM can be up to 30 nm, with the generated electromagnetic radiation being in the wavelength range from 400 nm to 800 nm. For other applications, FWHM can be up to 100 nm or more and / or reduced by filters if necessary, with the generated electromagnetic radiation being in the wavelength range from 800 nm to 2000 nm. The light generated by LED 12.1 is irradiated unfiltered onto measuring body 3 to ensure a high S / N ratio. In particular, the light generated by LED 12.1 is polychromatic with an intensity maximum at a wavelength in the UVA range of 340 nm. Alternatively, an LED can be used that generates light with an intensity maximum in the UVA range of 365 nm. The irradiation occurs at an intensity that does not cause acute damage to the skin, which is below the simple MED or below the MZB values.is significantly below the values caused by solar radiation. The light remitted by the skin of the subject 3 is guided through the light guide 4.2 to the photodiode of the detector unit 13, detected by the photodiode, and converted into measured values. The measured values are sent to the control unit 2 and stored in the control unit 2.
[0080] Control unit 2 then asks at 120 whether the second measurement of the skin of test subject 3 treated with protective agent has already been performed. If this is not the case, control unit 2 indicates this. To perform the second measurement 110 with applied protective agent, the protective agent is applied to the skin of test subject 3 130, e.g., according to ISO 24442 or 24444 in the amount of 2.0 mg / cm 2on the skin surface to be tested. The application 130 of the protective agent and the subsequent second measurement 110 are carried out at the same location on the measurement sample 3, in particular on the same location on the skin of a test subject, in order to ensure the reproducibility of the first and second measurements 110. Also to ensure reproducibility, the control unit 2 controls the beam source control 11 such that the beam source control 11 controls the LED 12.1 such that the light generated by the LED 12.1 is guided through the light guide 4.1 onto the skin of the test subject 3, wherein the intensity and / or exposure time of the first and second measurements 110 are coordinated with one another.
[0081] The light reflected by the skin of the test subject 3 is also detected by the photodiode of the detector unit 13 and converted into measured values. The measured values are sent to the control unit 2 and stored in the control unit 2. If the query 120 indicates that the second measurement 110 has already been performed, an evaluation 140 of the protective device is carried out. For this purpose, the control unit 2 executes a program for calculating the reflection spectrum T in viv o according to equation 1:
[0082] Equation 1 with T in ViV o as a function of wavelength A, SPF in VjV o the protection factor determined by the in vivo method 100, R o reflected intensity of the untreated skin of subject 3 as a function of wavelength A, R reflected intensity of the skin of subject 3 treated with protective agent as a function of wavelength A. The method 100 presented here requires a time expenditure of a few seconds to a few tens of seconds.
[0083] As an alternative to the method shown in Fig. 6 with one LED, this method can also be carried out in the same way with a multi-LED radiation source.
[0084] Fig. 7 shows an embodiment of the method 400 according to the invention for carrying out a combined in vivo reflection measurement 100 (see Fig. 5) taking into account the data of a transmission spectrum 200. According to the invention, the values of the transmission spectrum 200 are calculated (in silico).
[0085] If the amounts and properties of a protective agent's UV filter substances are known, the UV transmittance can be calculated, taking into account the film's irregularity and photodegradation. Based on the simulated UV transmittance, the SPF and all parameters that characterize UVA and / or UVB protection can be calculated in silico.
[0086] The in silico determination of the data of a transmission spectrum 200 is carried out according to ISO 24443. A plot of 2.0 g / cm is assumed. 2 Protective agent. The emitted radiation is assumed to be in the wavelength range from 280 nm to 500 nm (UVB to blue light), thus encompassing the wavelength range of the evaluation wavelength from a maximum of 280 nm to 500 nm.
[0087] The results of the evaluations of the in vivo remission spectrum 140 and the in silico transmission spectrum 200 are evaluated together 300. For this purpose, the hybrid transmission spectrum T hyb , calculated, where the in silico transmission spectrum T in S iiico using the reflection spectrum T in viv o is scaled:
[0088] The two results of the individual evaluations 140, 230 are combined and evaluated 300. For this purpose, the hybrid transmission spectrum T hyb, where the in vitro transmission spectrum T in S iiico using the reflection spectrum T in viv o is scaled:
[0089] The protective ability of the protective agent for the spectral range from UVA (320nm) to the HEV spectral range (450nm) SF is then calculated according to equation 4 (here E = IPD(Ä) is the
[0090] IPD spectrum; S = l(Ä) is the solar spectrum):
[0091] Eq. 4
[0092] The protectability of the protective agent in the area of interest for the present invention
[0093] Spectral range of blue light (400nm to 500nm) is determined according to equation 5 (here E = IPD(Ä) is the IPD spectrum; S = l(Ä) is the solar spectrum)
[0094] Eq.5 The protective ability of the protective agent from 400nm to 450nm SF (400nm-450nm) is determined according to equation 6 (here E = IPD(Ä) is the IPD spectrum; S = I(Ä) is the solar spectrum):
[0095] Eq.6
[0096] The protective ability of the protection agent for the spectral range of UVA (320-400nm) UVA- SF is then calculated according to equation 4 (here E = PPD(Ä) is the PPD spectrum; S = l(Ä) is the solar spectrum or UVA source for PPD-test.):
[0097] Eq. 7
[0098] The protective ability of the protective agent for the spectral range from UVB to UVA (280-400nm) UV-SF is then calculated according to equation 4
[0099] Eq. 8
[0100] In all equations for SF or UVA-SR, an optional correction function F (SF) = SF_corr or F (UVA-SF) = UVA-PF_corr is used, which describes, for example, skin-type-dependent differences. A correction function makes values of different skin types comparable and returns a corrected value SF korr or UVA-PF korr out of.
[0101] For example, F can be a linear factor (ie F(SF)=SF*C) or an exponential function (ie F(SF)=SF C ). C can depend, for example, on the skin type or the ITA° value. As shown in Eq. 4, the formulas in Eqs. 2 to 8 can be written as follows: Eq. 9
[0102] Since the in vivo value is measured without photodegradation, photodegradation should be appropriately taken into account. This can be done by setting T_in silico with (T insaico irr (X) and without photodegradation and a spectral quotient is calculated from it
[0103] Eq. 10
[0104] This will then
[0105] Eq.10 calculated
[0106] The method can be calibrated using suitable reference methods such as electron spin resonance spectroscopy.
[0107] B EZ UG S CHARACTERS LIST
[0108] 1 SPF evaluation system
[0109] 2 Control device
[0110] 3 Sample / measuring body
[0111] 4.1 , 4.2 Optical fiber / fiber bundle
[0112] 5 Probe head
[0113] 6 Measuring device
[0114] 10 Evaluation device
[0115] 11 Beam source control
[0116] 12 Beam source device
[0117] 12.1 Beam source
[0118] 13 Detection unit
[0119] 21 Connection beam source control - control device
[0120] 22 Connection detector / spectrometer - control device
[0121] 23 Connection beam source control - beam source device
[0122] 24 Connection beam source control - detection unit
[0123] 25 Connection control device - evaluation device
[0124] 100 Methods for taking a spectroscopic measurement (in vivo)
[0125] 110 Performing a Reflectance Spectrum Measurement
[0126] 120 queries
[0127] 130 orders of the protective agent
[0128] 140 Evaluation of the reflection spectrum
[0129] 200 Procedures for determining the data of a
[0130] T ransmission spectrum
[0131] 300 Determination of a protection factor
[0132] 400 methods for determining a protection factor
Claims
PATENT CLAIMS 1. Method (400) for determining a protection factor comprising the steps of: • Emitting radiation from a radiation source (12.1), wherein the emitted radiation comprises light with an irradiation wavelength between 280 nm and 2000 nm, preferably 280 to 800 nm, particularly preferably the range from 280 to 500 nm, • Irradiating a measuring body (3) with the emitted radiation, • Detection of the radiation remitted by the irradiated measuring body (3) with a detection wavelength, • Evaluation of the protection factor of a protective agent with an evaluation wavelength from the remitted radiation and a transmission spectrum, wherein the data of a transmission spectrum are used for the evaluation of the protection factor of the protective agent, wherein the evaluation wavelength is different from the wavelength range of the irradiation wavelength and / or the detection wavelength, and wherein the data of the transmission spectrum are in silico data.
2. Method (400) for determining a protection factor according to claim 1, characterized in that the wavelength range of the transmission spectrum includes the evaluation wavelength.
3. Method (400) for determining a protection factor according to claim 1 or 2, characterized in that the evaluation wavelength is the wavelength range from 280 nm to 2000 nm, preferably the wavelength range from 280 nm to 800 nm or particularly preferably the wavelength range from 280 nm to 500 nm and / or the Wavelength range from 400 nm to 500 nm and / or the wavelength range from 400 nm to 450 nm.
4. Method (400) for determining a protection factor according to claim 3, characterized in that the evaluation of the protective ability of the protective agent for light in a Wavelength range from 400nm to 500nm in a range determined by the evaluation of the Protection ability of the protective agent for light in a wavelength range of 280nm to 400nm separate process.
5. Method (400) for determining a protection factor according to claim 4, characterized in that the evaluation of the protective ability of the protective agent for light in a Wavelength range from 400nm to 500nm in a range determined by the evaluation of the Protection ability of the protective agent for light in a wavelength range of 280nm to 400nm different processes.
6. Method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the wavelength range of the irradiation wavelength or the Wavelength range of the detection wavelength is smaller than the Wavelength range of the evaluation wavelength.
7. Method (400) for determining a protection factor according to claim 6, characterized in that the wavelength range of the irradiation wavelength or the wavelength range of the detection wavelength in the wavelength range of the evaluation wavelength is smaller than the wavelength range of the evaluation wavelength.
8. Method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the range of the irradiation wavelength and / or the wavelength range of the detection wavelength is less than 100 nm, preferably less than 50 nm and particularly preferably less than 25 nm.
9. Method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the irradiation wavelength and / or the detection wavelength comprises only light with wavelengths outside the wavelength range from 400 nm to 450 nm.
10. Method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the irradiation wavelength and / or the detection wavelength comprises only light with wavelengths outside the wavelength range from 400 nm to 500 nm.
11. Method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the evaluation wavelength comprises wavelengths outside the wavelength range from 400nm to 500nm.
12. Method (400) for determining a protection factor according to claim 11, characterized in that the evaluation wavelength comprises wavelengths A with A < 400nm.
13. Method (400) for determining a protection factor according to claim 12, characterized in that the evaluation wavelength comprises wavelengths A with 320nm < A < 400nm.
14. Method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the emission of radiation occurs from a single beam source (12.1), wherein the irradiation wavelength of the one beam source (12.1) comprises light in a wavelength range between 280nm and 500nm.
15. Method (400) for determining a protection factor according to claim 14, characterized in that the individual radiation source (12.1) is controllable.
16. Method (400) for determining a protection factor according to claim 14 or 15, characterized in that the control of the radiation source (12.1) is carried out by a radiation source control (11).
17. Method (400) for determining a protection factor according to claim 16, characterized in that the wavelength, the exposure time and / or the intensity of the individual beam sources (12.1) are controlled by controlling the beam source (12.1).
18. Method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the transmission spectrum is adapted using the detected remitted radiation.
19. Method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the radiation is emitted in vivo onto human skin.
20. Method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the evaluation of the protective ability of the protective agent is carried out from two measurements.
21. Method (400) for determining a protection factor according to claim 20, characterized in that a first measurement is carried out before the protective agent is applied to the measuring body (3).
22. Method (400) for determining a protection factor according to claim 20 or 21, characterized in that a second measurement is carried out after the application (130) of the protective agent on the measuring body (3).
23. Method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the radiation source (12.1) generates polychromatic radiation, wherein the generated polychromatic radiation is radiated unfiltered onto the measuring body (3).
24. Method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the spectroscopic measurement (100) is carried out exclusively in vivo.
25. SPF evaluation system (1) for the investigation of the protection factor of Protective agents containing the following components: • a measuring device (6) with a beam source device (12), wherein the beam source device (12) has a beam source (12.1), a detector unit (13), • a control unit (2) for controlling the measuring device (6), • an evaluation unit (10).
26. SPF evaluation system (1) for investigating the protection factor of protective agents according to claim 25, characterized in that the SPF evaluation system (1) is suitable for evaluating the protective ability of To investigate protective agents for protection against light in an evaluation wavelength range.
27. SPF evaluation system (1) for examining the protection factor of protective agents according to claim 25 or 26, characterized in that the SPF evaluation system (1) has exactly one measuring device (6).
28. SPF evaluation system (1) for examining the protection factor of protective means according to claim 27, characterized in that the precisely one measuring device (6) has precisely one radiation source device (12).
29. SPF evaluation system (1) for investigating the protection factor of protective means according to claim 28, characterized in that the precisely one radiation source device (12) has precisely one radiation source (12.1).
30. SPF evaluation system (1) for examining the protection factor of protective means according to claim 28 or 29, characterized in that the precisely one radiation source device (12) is controlled by precisely one control unit (2) for Control of the measuring device (6) can be controlled.
31. SPF evaluation system (1) for examining the protection factor of protective agents according to one or more of claims 27 to 30, characterized in that the precisely one measuring device (6) has precisely one detection unit (13).
32. SPF evaluation system (1) for examining the protection factor of protective agents according to claim 31, characterized in that the exactly one detection unit (13) has exactly one detector.
33. SPF evaluation system (1) for investigating the protection factor of protective agents according to claim 31 or 32, characterized in that the precisely one detection unit (13) can be controlled by precisely one control unit (2) for controlling the measuring device (6).
34. SPF evaluation system (1) for examining the protection factor of protective agents according to one or more of claims 26 to 33, characterized in that the precisely one beam source device (12) is suitable for emitting light with an irradiation wavelength, wherein the wavelength range of the irradiation wavelength is smaller than the wavelength range of the evaluation wavelength.
35. SPF evaluation system (1) for examining the protection factor of protective agents according to one or more of claims 26 to 34, characterized in that the precisely one detection unit (13) is suitable for detecting light with a detection wavelength, wherein the wavelength range of the detection wavelength is smaller than the wavelength range of the evaluation wavelength.
36. SPF evaluation system (1) for investigating the protection factor of protective agents according to claim 34 or 35, characterized in that the wavelength range of the irradiation wavelength or the Wavelength range of the detection wavelength in the wavelength range of the evaluation wavelength is smaller than the wavelength range of the evaluation wavelength.
37. SPF evaluation system (1) for investigating the protection factor of protective agents according to one or more of claims 34 to 36, characterized in that the range of the irradiation wavelength and / or the wavelength range of the detection wavelength is less than 100 nm, preferably less than 50 nm, and particularly preferably less than 25 nm.
38. SPF evaluation system (1) for investigating the protection factor of protective agents according to one or more of claims 25 to 37, characterized in that the SPF evaluation system (1) has precisely one control unit (2).
39. SPF evaluation system (1) for examining the protection factor of protective agents according to one or more of claims 25 to 38, characterized in that the SPF evaluation system (1) is suitable for examining the protective ability of protective agents for protection against light and / or for evaluating the protection factor of a protective agent using measurement data exclusively from a measurement data device (6).