Test chamber for photostability testing

Abstract

The present disclosure provides ultraviolet filters for use in photostability test chambers, particularly filters designed to allow for air ventilation and maintenance of a desired temperature at the sample level during light exposure testing.

Description

[Technical Field]

[0001] This disclosure provides a filter for limiting the amount of transmitted ultraviolet light for use in a photostability test chamber. The filter enables more consistent application of visible light and ultraviolet light during stability testing of pharmaceutical products. [Background technology]

[0002] US2008 / 169428(A1) discloses a device comprising a chamber in which a UV irradiation source and a housing are arranged, the housing comprising a bottom wall for mounting a specimen, a UV irradiation filter facing the bottom wall, and a plurality of side walls interconnecting the bottom wall and the UV irradiation filter.

[0003] During the handling, transportation, management, and storage of biological materials and pharmaceutical agents, physical and environmental conditions such as light, temperature, and humidity can degrade the composition of the materials. Therefore, to ensure the safety and efficacy of pharmaceutical products under these conditions, it is necessary to perform photostability tests on pharmaceutical products.

[0004] The requirements for photostability testing are determined by the ICH Harmonized Tripartite Guidelines for Stability Testing of New Drug Substances and Products Q1B. The ICH guidelines provide guidance for photostability testing studies of new pharmaceutical substances and products, and are mandatory for the entry of these new drugs into the global market.

[0005] Current minimum ICH requirements result in nearly three times the normal exposure in the ultraviolet (UV) range during photostability testing. This excessive UV exposure can cause significant degradation of the drug's composition, creating a need for photostability testing methods that reduce unnecessary excessive exposure in the UV range. Methods or structures to prevent excessive UV exposure are needed to ensure that light exposure does not lead to unacceptable changes in commercially available drug substances and drug products. [Overview of the Initiative]

[0006] In some embodiments, provided herein are filters for use in a photostability test chamber, the filter comprising: a first planar structure configured to extend across a horizontal cross-section of the photostability chamber; a first baffle spaced apart from a first edge of the first planar structure and extending from the lower surface of the first planar structure; a second baffle spaced apart from a second edge of the first planar structure and extending from the lower surface of the first planar structure, wherein the first and second edges are opposing edges of the first planar structure; a first through-opening in the first planar structure located between the first edge and the first baffle; and a second through-opening in the first planar structure located between the second edge and the second baffle, wherein the filter is configured to be suspended within the photostability chamber, and the first planar structure comprises a polymer that limits the transmittance of ultraviolet light to at least 30%.

[0007] In additional embodiments, provided herein are photostability test chambers comprising: an internal chamber having a top surface, a bottom surface, and two opposing side walls; a light source located on the top surface; a sample platform positioned above the bottom surface; and a filter as described herein, positioned at least 6 cm above the sample platform and below the light source, the filter being supported by internal screws on the two opposing side walls; an air inlet vent on a first side wall; and an air outlet vent on a second side wall, wherein the first baffle of the filter is configured to direct the airflow from the air inlet vent, through a first through-opening, across a first planar structure, and through a second through-opening, and also into the sample area below the filter and out of the air outlet vent.

[0008] This disclosure also relates to a method for exposing a compound to ultraviolet and visible light, comprising positioning the compound on a sample platform of the photostability test chamber of the present invention, and exposing the compound to ultraviolet and visible light from a single light source, wherein the ultraviolet and visible light pass through a filter described herein, and the ultraviolet light is filtered before reaching the compound. Additional samples may also be placed on the filter itself to compare samples below and above the filter simultaneously. [Brief explanation of the drawing]

[0009] [Figure 1] This specification shows filters for use in a photostable chamber. [Figure 2] This document outlines the photostability test chamber described herein. [Figure 3-1] Figures 3A to 3C show internal diagrams of the photostability test chamber described herein. [Figure 3-2] Continuation of Figure 3-1. [Figure 4] The temperatures at the sample and filter levels for the photostable chamber designs are shown. 1) No filter, 2) Design II: Flat acrylamide UV filter, and 3) Design III: Through-holes and baffles added to the photostable chamber for temperature control. [Figure 5] This shows the experimental setup for a light exposure test of a sample in a photostability test chamber. The sample vial S and the coated vial (dark control (DC)) are placed on the sample rack. External temperature and UV exposure are measured, respectively, by a meter ETUM positioned at the sample level. The external temperature probe is not shown in Figure 5. [Figure 6A] The effects of light exposure on the concentration of model molecules, measured by UV-vis (ultraviolet-visible) spectroscopy, are shown. Figure 6A shows the loss of content in insoluble aggregates for albumin and mAb IV after the most severe UV exposure conditions (3x ICH minimum requirement for UV light, or 3.6 million lux hours of 1200 Wh / m2 UV exposure and visible light exposure). [Figure 6B] The effect of light exposure on the concentration of model molecules, as measured by UV-vis (ultraviolet-visible) spectroscopy, is shown. Figure 6B shows that no loss of protein content was observed for all molecules tested in a photostable chamber with an additional UV filter (exposure of 3.6 million lux of visible and negligible UV light). [Figure 7A] Size exclusion—shows the effect of light exposure on model molecules measured by high-performance liquid chromatography (SE-HPLC). Figure 7A shows the loss in the main peak for selected molecules when exposed to UV and visible light conditions up to 3x ICH minimum requirements for UV light (1200 Wh / m2 UV irradiation and 3.6 million lux hours of visible light exposure), indicating a decrease in sample purity. [Figure 7B] Size exclusion—shows the effect of light exposure on model molecules measured by high-performance liquid chromatography (SE-HPLC). Figure 7B shows the effect of visible light exposure (3.6 million lux exposure time in visible light, with negligible UV light due to the presence of a UV filter) on the sample purity of model molecules measured by SE-HPLC. The relevant change in purity is not observed with visible light exposure alone. [Figure 8A] The effects of the UV filter on different experimental parameters are shown. Figure 8A shows the effect of the UV filter on the irradiation level measured at the sample level. When using the filter, a reduction of more than 98% was observed in UV irradiation. [Figure 8B] The effects of the UV filter on different experimental parameters are shown. Figure 8B shows the significant effect of the UV filter on the temperature measured at the sample level on the sample platform. As shown, there was no difference in the temperature measured in the chamber with or without the filter. [Modes for carrying out the invention]

[0010] The manufacture and distribution of high-quality, uncompromising pharmaceutical products require photostability testing procedures that effectively measure the significant impact of light exposure on product integrity. For minimum exposure, the current ICH Q1B guidelines specify a minimum exposure exceeding 1.2 million lux-hours (visible range 400-800 nm) and 200 W*-hours / m². 2 This requires exceeding the UV range of 320-400 nm. These photostability test requirements have been particularly challenging because, when using a single light source for both wavelength ranges, excessive exposure to ultraviolet light would exceed 200% when following the ICH Q1B guidelines for minimum exposure requirements in the visible region. Under conditions of excessive UV light exposure, proteins absorb ultraviolet light, and the energy is transferred along photochemical pathways that lead to the potential degradation of protein structures, resulting in compromised safety and efficacy of the drug product.

[0011] Currently, no single light source can provide the combination of simultaneous UV and visible light exposure levels required by regulatory requirements without causing excessive exposure in the UV range. Due to this limitation, Option 2 of the ICH guidelines is often used, requiring two separate experimental setups, each with a different light source, one emitting only UV light and the other only visible light. This setup is not ideal due to the potential limitations on representative materials, time, and resources required. Therefore, there is a great need for a photostability test method and apparatus that allows simultaneous exposure to UV and visible light while meeting the requirements of ICH Q1B.

[0012] Adding an anti-UV filter to a test chamber raises potential issues related to chamber temperature, as well as potential aging of the filter material and a decrease in transmittance in the visible range. Due to the temperature rise caused by the increased heat generated by the UV light source, photostability equipment typically includes an air cooling system to control the temperature within a specific range. This disclosure provides a filter and method for filtering UV light while allowing visible light to pass through a photostability test chamber, in order to enable regulatory requirements for photostress testing in a controlled temperature environment.

[0013] In embodiments, provided herein are filters for use in a photostable chamber. Figure 1 shows an exemplary filter 100, which includes a first planar structure 102 configured to spread across the horizontal cross-section of a photostable chamber. Figure 2 shows the arrangement of the filter 100 within a photostable chamber 200, illustrating how the filter spreads across the horizontal cross-section (i.e., the width of the chamber). Figure 3A shows an additional view of the inside of the photostable chamber 200 with the filter 100 spread across the cross-section inside the chamber.

[0014] As shown in Figure 1, in an embodiment, the filter 100 includes a first baffle 104 spaced apart from the first edge of the first planar structure 102 and extending from the lower surface of the first planar structure 102. As used herein, “baffle” refers to a suitable solid structure made of the same material as the filter 100, extending below the first planar structure 102. The baffle can be formed from the same material as the filter 100, particularly the first planar structure 102 (i.e., in a molding process), or it can be structurally attached to the planar structure 102 via adhesives, tacks, welds, screws, various tongue mechanisms and groove mechanisms, etc. Figure 3A provides another view of the first baffle 104 inside the photostable chamber 200. As used herein, “planar structure” refers to a filter element that is substantially flat, rectangular, or square in shape (other shapes may also be used), preferably having a thickness of about 1 mm to about 5 cm, more preferably about 10 mm to about 1 cm, or about 10 mm to about 0.5 cm.

[0015] As shown in FIG. 1, in an embodiment, the filter 100 includes a second baffle 106 spaced from a second edge of the first planar structure 102 and extending from the lower surface of the first planar structure 102, and the first edge (150) and the second edge (152) are parallel and are opposite edges of the first planar structure. The second baffle 106 can also be seen inside the light stability chamber 200 in FIG. 3A.

[0016] As shown in FIG. 1, in an embodiment, the filter 100 includes a first through opening 108 in the first planar structure 102 located between the first edge and the first baffle 104. As used herein, a "through opening" refers to a hole cut completely through the first planar structure 102. The through opening can be cut as a single hole or multiple holes, or as a continuous or broken slit, in the first planar structure 102 including holes of different shapes, lengths, and widths between the first edge and the first baffle 104. An additional view of the first through opening 108 is shown in FIG. 3A inside the light stability chamber 200.

[0017] As shown in FIG. 1, in an embodiment, the filter 100 includes a second through opening 110 in the first planar structure 102 located between the second edge and the second baffle 106. The second through opening 110 is shown inside the light stability chamber in FIG. 3A.

[0018] As shown in FIG. 3A, in an embodiment, the first edge of the filter 100 further includes a support ledge 316 extending below the first planar structure 102. As used herein, a "support ledge" refers to a solid extension from the lower surface of the first planar structure 102 at the first edge of the filter 100. The support ledge can be formed from the same material as the filter 100 or can be structurally attached to the planar structure 102 via adhesives, glues, welding, screws, various tongue mechanisms, and groove mechanisms.

[0019] In an embodiment, the first planar structure 102 preferably has a length of about 20 cm to about 50 cm and a width of about 25 cm to about 50 cm and contains a polymer that limits the ultraviolet transmittance to at least 30%. In an additional embodiment, the length of the first planar structure 102 may be about 25 cm to about 40 cm or about 30 cm, and the width may be about 35 cm to about 45 cm or about 30 cm. In an additional embodiment, the length of the first planar structure 102 may be about 30 cm to about 45 cm or about 35 cm, and the width may be about 40 cm to about 50 cm or about 35 cm. In an additional embodiment, the length of the first planar structure 102 may be about 35 cm to about 50 cm or about 40 cm, and the width may be about 45 cm to about 55 cm or about 40 cm. In an additional embodiment, the length of the first planar structure 102 can be about 40 cm to about 55 cm, or about 45 cm, and the width can be about 50 cm to about 60 cm, or about 45 cm. In an additional embodiment, the length of the first planar structure 102 can be about 45 cm to about 60 cm, or about 50 cm, and the width can be about 55 cm to about 65 cm, or about 50 cm. In an additional embodiment, the length of the first planar structure 102 can be about 50 cm to about 65 cm, or about 55 cm, and the width can be about 60 cm to about 70 cm, or about 65 cm. In an additional embodiment, the length of the first planar structure 102 can be about 55 cm to about 70 cm, or about 60 cm, and the width can be about 65 cm to about 75 cm, or about 70 cm. In an additional embodiment, the length of the first planar structure 102 may be about 60 cm to about 75 cm, or about 65 cm, and the width may be about 70 cm to about 80 cm, or about 75 cm. In an additional embodiment, the length of the first planar structure 102 may be about 65 cm to about 80 cm, or about 70 cm, and the width may be about 75 cm to about 85 cm, or about 70 cm. In an additional embodiment, the length of the first planar structure 102 may be about 70 cm to about 85 cm, or about 75 cm, and the width may be about 80 cm to about 90 cm, or about 85 cm.In additional embodiments, the length of the first planar structure 102 can be about 75 cm to about 90 cm, or about 80 cm, and the width can be about 85 cm to about 95 cm, or about 90 cm.

[0020] In embodiments, the first planar structure 102 provided herein has width and length dimensions, including the dimensions provided herein, that are appropriately spread within a photostable chamber configured to be positioned.

[0021] In an embodiment, provided herein is a filter 100 in which the polymer limits the ultraviolet transmittance to at least 50%. In a further embodiment, the polymer of the filter 100 limits the ultraviolet transmittance to at least about 20%, at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or the ultraviolet transmittance to about 50% to about 95%, about 60% to about 95%, about 70% to about 95%, or about 80% to about 95%. Limiting the ultraviolet transmittance to a desired percentage (%) is equivalent to limiting the UV transmittance (e.g., W*hours / m²). 2 This indicates that the measured value decreases by that percentage amount.

[0022] Exemplary materials for use in filter 100, which provides desired UV light filtration, include various glasses and polymers, preferably including acrylamide. Additional materials that can be used in filter 100 include acetates and various acrylics. Glass materials containing UV filtering material dispersed therein can also be used.

[0023] In further embodiments, provided herein are photostability chambers for use in UV and visible light testing of pharmaceutical products. Figure 2 shows an exemplary photostability chamber 200 having a top surface 206, a bottom surface 302, and an inner chamber having a first chamber sidewall 308 and a second chamber sidewall 310 (see Figure 3). As used herein, “top surface” refers to a solid structure extending into the horizontal uppermost section of the photostability test chamber 200. As used herein, “bottom surface” refers to a solid structure extending into the horizontal base of the photostability test chamber 200. As used herein, “chamber sidewall” refers to a housing extending vertically between the top surface and the bottom surface of the photostability chamber 200 (i.e., the height of the chamber).

[0024] As shown in Figure 2, in this embodiment, the photostable chamber 200 includes a light source 202 located on the top surface 206. As used herein, “light source” refers to a device that emits both UV and visible light into the photostable chamber 200 from the top surface 206.

[0025] As shown in Figure 2, in this embodiment, the photostability chamber 200 includes a sample platform 204 positioned above the bottom surface. As used herein, “sample platform” refers to an additional surface raised above the bottom surface of the photostability chamber 200 on which a sample can be placed for testing. The sample platform may be a solid surface, a metal rack, or a grid.

[0026] As shown in Figure 3A, in this embodiment, the filter 100 is configured to be suspended on an internal screw 314 within the photostabilizing chamber 200. As used herein, “internal screw” refers to a fastener inserted into or located within the first chamber sidewall 308 or the second chamber sidewall 310. The internal screw 314 can be attached to the chamber sidewall or laterally by drilling, adhesive, and other adhesives. Other supports within the photostabilizing chamber 200 can also be used to support the filter 100, which extends to the dimensions of the chamber.

[0027] In this embodiment, the photostable chamber 200 includes a filter 100 positioned at least 6 cm above the sample platform 204 and 20 cm below the light source 202, the filter 100 being supported by internal screws 314 on the first chamber sidewall 308 and the second chamber sidewall 310. Additional spatial relationships can also be used to position the filter 3 cm to 20 cm above the sample platform, or 5 cm to 10 cm above the sample platform, while maintaining a distance of approximately 15 cm to 30 cm below the light source.

[0028] As shown in Figure 3A, in this embodiment, the photostability chamber 200 includes an air inlet vent 304 in the first sidewall chamber 308. As used herein, “air inlet vent” refers to an opening in the first sidewall chamber 308 through which air or gas passes into the photostability chamber 200. A closer look at the air inlet 304 can be seen in Figure 3B, which shows the ventilation of the photostability chamber 200 through the air inlet 304, including the direction (in) of the airflow. The air inlet is used to provide air to maintain the temperature of the photostability chamber within a desired range and allows the temperature to be raised or lowered as desired to test various conditions on a sample.

[0029] As shown in Figure 3A, in this embodiment, the photostability chamber 200 includes an air outlet vent 306 in the second side wall 310. As used herein, “air outlet vent” refers to an opening in the second side wall chamber 310 through which air or gaseous liquid circulating within the photostability chamber 200 passes out of the chamber. An additional diagram of the air outlet 306 is shown in Figure 3C, where the airflow is discharged from the photostability chamber 200.

[0030] As shown in Figure 3A, in this embodiment, the photostable chamber 200 includes an irradiation intensity sensor 312. As used herein, “irradiation intensity sensor” refers to a device that measures the radiant flux (radiant force) received by a surface per unit area.

[0031] As shown in Figures 3B and 3C, in this embodiment, the first baffle 104 of the filter 100 is configured to direct the airflow from the air inlet vent 304, through the first through-opening 108, across the first planar structure 102, and into the sample area below the filter 100, and then through the second through-opening 110 or the sample area, and out of the air outlet vent 306. This air circulation is determined to be important for maintaining the temperature of the sample and chamber at a desired value or range, and also allows for testing of the sample above the filter 100, if so desired.

[0032] Filter 100 can also be inserted into the photostability test chamber at a position rotated 180° around the vertical axis from the position shown in Figures 3A to 3C. In this case, the first edge, the first through-opening, and the first baffle function as the second edge, the second through-opening, and the second baffle, respectively, and vice versa.

[0033] In additional embodiments, provided herein are compounds that are administered at a concentration of at least about 200 W*h / m². 2 A method of exposure to ultraviolet light and visible light of at least about 1.2 million Lux*h comprises positioning a compound on a sample platform 204 of a photostability test chamber 200 and exposing the compound to ultraviolet and visible light from a single light source 202, wherein the ultraviolet and visible light pass through a filter 100, and the ultraviolet light is filtered through the filter 100 before reaching the compound. Figure 5 depicts the experimental setup of this method inside the photostability chamber 200, with the sample placed on the sample platform 204 to test its sensitivity to light exposure.

[0034] In embodiments of the method described herein, the compound is exposed to visible light at least about 1.2 million Lux*h, but at about 500 W*h / m 2 The compound is exposed to ultraviolet light not exceeding a certain level. Preferably, in this method, the compound is exposed to visible light of at least about 1.2 million Lux*h, but about 400 W*h / m 2Ultraviolet rays not exceeding, more preferably about 350 W*h / m 2 Ultraviolet rays not exceeding, about 300 W*h / m 2 Ultraviolet rays not exceeding, about 250 W*h / m 2 Ultraviolet rays not exceeding, or about 200 W*h / m 2 Results are brought about by being exposed to ultraviolet rays not exceeding. The temperature above the filter 100 is maintained at about 30°C to about 40°C, and the temperature of the sample is maintained at about 20°C to about 40°C.

Example

[0035] Design and test of the photostability chamber As described herein, the provided method enables control of UV light exposure and temperature in a photostability test chamber. The addition of a filter that limits overexposure of UV light enables Option 1 of the ICH Q1B test, where one lamp that combines UV and visible light is utilized and the UV and visible light are separated within the photostability test chamber. FIG. 2 depicts this experimental setup with one lamp source 202 that emits both UV and visible light.

[0036] To maintain air circulation in the photostability chamber, the filter described herein employs passage (i.e., holes or slits) on the side of the filter so that air ventilation is possible throughout the light chamber, as illustrated in FIGS. 3A - 3C. The sample is preferably fixed on a sample platform, enabling placement in a horizontal orientation (see FIG. 5). If necessary, the sample can also be placed on the filter for testing. The filter is designed to be easily inserted or removed from the chamber by simply placing the filter on the existing screws within the photostability chamber without the need to fixedly attach to the opposing sidewalls (see FIGS. 3A - 3C). In addition, the filter is designed to be large enough to allow for maximum sample testing and uniform exposure of the sample to the filter. FIGS. 3A - 3C depict the experimental setup of the sample and filter placement, as well as the air flow within the test chamber.

[0037] To test the effectiveness of the filters described herein, samples were exposed to UV light in a photostability test chamber without a filter, a photostability test chamber with a flat acrylamide UV filter (Design II), and a photostability test chamber with an air-through opening and baffle added for temperature control within the light chamber (Design III). Photodegradation and temperature-dependent changes were compared in the three different experimental setups. Figure 4 shows the sample-level and filter-level temperatures in the three different photostability test experimental setups. As illustrated, in Design III (filter with through opening and baffle), temperatures were maintained at approximately 20–40°C both above and below the filter.

[0038] Table 1 below highlights the experimental setup of the method used to test the significant effects of UV and visible light versus visible light only when a UV filter is added during light exposure in the chamber. Samples were exposed with and without the UV filter under the following settings, as shown in Figure 5. UV irradiation below the filter was 1 W / m² at a chamber temperature of 25+5°C. 2 It was measured to be below that. The lamp irradiation was set to 300-800 nm on the equipment, at 650 W / m². 2 (30W / m 2 Four sampling points were used (T0-T3), including UV irradiation. [Table 1]

[0039] The samples were examined for changes that may occur after light exposure, according to ICH Q1B. These test methods can demonstrate the relevant changes due to photodegradation of the samples.

[0040] Figures 6A and 6B show the results of UV-Vis spectroscopic analysis performed after photoexposure tests in a photostability test chamber with and without a UV filter for 1) albumin, 2) insulin, 3) mAb I, 4) mAb III, 5) mAb IV, and 6) mAb II (mAb represents an exemplary monoclonal antibody), both with and without a UV filter (Figure 6A). Figure 6A shows that without a UV filter, the most severe light exposure conditions (3x ICH) result in a loss of content for albumin and mAb IV in insoluble aggregates formed in the sample under test. Figure 6B shows that exposure of the sample to the most severe light conditions (3x ICH) with a UV filter did not result in a loss of protein content for any of the molecules under test. These results demonstrate the significant impact of excessive UV light exposure on the content of the drug product under test. These results also provide support for the efficiency of UV filters in limiting the exposure of samples to UV light and thus preventing the degradation of the drug samples being tested, when following the ICH Q1B guidelines.

[0041] Figures 7A and 7B show the results of size exclusion chromatography (SE-HPLC) experiments performed after light exposure tests in a photostability test chamber with and without a UV filter (Figure 7A) for 1) albumin, 2) insulin, 3) mAb I, 4) mAb III, 5) mAb IV, and 6) mAb II molecules, and with and without a UV filter (Figure 7B). Figure 7A shows that the sample purity of albumin, insulin, mAb I, mAb III, and mAb IV decreases after exposure to light (3x ICH) without a UV filter, as evidenced by the loss of the main peak (percent area) of the molecule being tested. No change in purity is observed for mAb II under these light exposure conditions, as this molecule is very stable to various stresses, as confirmed by previous experiments. Figure 7B shows that the addition of a UV filter in the photostability test chamber did not result in a significant decrease in the major peaks (area percentage) of albumin, insulin, mAb I, mAb III, and mAb IV between T0 (no light exposure) and exposure to the most severe light conditions (3x ICH). These results demonstrate the significant impact of excessive UV light exposure on the purity of the drug product being tested. These results also provide support for the usefulness of UV filters in maintaining the quality of drug samples during photostability testing with light exposure.

[0042] Figures 8A and 8B show the effects of adding a UV filter in the photostability test chamber on UV irradiation at the sample level (8A) and temperature at the sample level (8B). Figure 8A shows that in the photostability test chamber without a UV filter, UV irradiation at the sample level is 30-35 W / m² over 40 hours of light exposure. 2This indicates that the results were within the specified range. The use of a UV filter in the chamber resulted in a 98% reduction in the level of UV irradiation observed at the sample level, which was detected below 1 W / m2 over 40 hours of light exposure. With or without the UV filter, the temperature at the sample level was not affected by the addition of the UV filter, as shown in Figure 8B. Furthermore, there was no significant difference in temperature at the sample level with or without the filter. These results demonstrate that using a UV filter design in a photostability test chamber reduces the UV irradiation exposed to the sample and maintains an appropriate temperature of approximately 5°C to 40°C at the sample level.

[0043] In addition to meeting UV, visible light, and temperature requirements, the present invention is long-lasting. Made from acrylic material, it has a slow decomposition rate without changes in material and optical properties over time. Furthermore, this material is heat-resistant, easily cut into various shapes, and adaptable to various equipment setups. Transmittance in the visible light and longer wavelength ranges remains unchanged.

[0044] Additional exemplary embodiments Embodiment 1 is a filter for use in a photostability test chamber, the filter comprising: a first planar structure configured to extend across the horizontal cross-section of the photostability chamber; a first baffle spaced apart from a first edge of the first planar structure and extending from the lower surface of the first planar structure; a second baffle spaced apart from a second edge of the first planar structure and extending from the lower surface of the first planar structure, wherein the first and second edges are opposing edges of the first planar structure; a first through-opening in the first planar structure located between the first edge and the first baffle; and a second through-opening in the first planar structure located between the second edge and the second baffle, wherein the filter is configured to be suspended within the photostability chamber, and the first planar structure comprises a polymer that limits the transmittance of ultraviolet light to at least 30%, the filter for use in a photostability chamber according to Embodiment 7.

[0045] Embodiment 2 includes the filter of Embodiment 1, wherein the first edge and the second edge are parallel.

[0046] Embodiment 3 includes the filter of Embodiment 1, wherein the polymer limits the transmittance of ultraviolet light to at least 50%.

[0047] Embodiment 4 includes the filter of Embodiment 1, wherein the first baffle extends below the second baffle.

[0048] Embodiment 5 includes the filter of Embodiment 1, wherein the first edge further comprises a support ledge extending below the first planar structure.

[0049] Embodiment 6 includes the filter of Embodiment 1, wherein the first planar structure has a length of about 30 cm to about 50 cm and a width of about 25 cm to about 40 cm.

[0050] Embodiment 7 is a photostability test chamber comprising an internal chamber having a top surface, a bottom surface, and two opposing side walls; a light source located on the top surface; a sample platform positioned above the bottom surface; and a filter of Embodiment 1, positioned at least 6 cm above the sample platform and below the light source, the filter being supported by internal screws on two opposing side walls, an air inlet vent on the first side wall, and an air outlet vent on the second side wall, wherein the first baffle of the filter is configured to direct the airflow from the air inlet vent, through a first through-opening, across a first planar structure, through a second through-opening, and below the filter into the sample area and outside the air outlet vent.

[0051] Embodiment 8 includes a photostable chamber of Embodiment 7, in which the filter is not fixedly attached to the opposing side walls.

[0052] Embodiment 9 includes a photostable chamber from Embodiment 7, in which a first baffle and a second baffle help distribute the airflow above and below the filter.

[0053] Embodiment 10 includes a light source that includes a photostable chamber from Embodiment 7, which emits ultraviolet and visible light.

[0054] Embodiment 11 includes a photostable chamber of Embodiment 7, wherein the sample platform is a metal rack or a metal plate.

[0055] Embodiment 12 includes a photostable chamber from Embodiment 7, in which a filter limits the transmittance of ultraviolet light from the light source to at least 50% as it reaches the sample platform.

[0056] Embodiment 13 includes a photostable chamber from Embodiment 7, further comprising an irradiation intensity sensor.

[0057] Embodiment 14 includes a photostable chamber from Embodiment 7, in which the filter is positioned 20 cm below the light source.

[0058] Embodiment 15 includes a photostable chamber from Embodiment 7, in which the filter is positioned approximately 9 cm to 12 cm above the sample platform.

[0059] Embodiment 16 is a method for exposing a compound to ultraviolet and visible light, comprising positioning the compound on a sample platform of a photostability test chamber according to Embodiment 7, and exposing the compound to ultraviolet and visible light from a single light source, wherein the ultraviolet and visible light pass through the filter of Embodiment 1, and the ultraviolet light is filtered before reaching the compound.

[0060] Embodiment 17 includes the method of Embodiment 16, wherein the temperature above the filter is maintained at approximately 5°C to approximately 40°C.

[0061] Embodiment 18 includes the method of Embodiment 16, wherein the compound is exposed to ultraviolet light at least about 200 W*h / m2.

[0062] Embodiment 19 includes the method of Embodiment 16, wherein the compound is exposed to visible light at least about 1.2 million Lux*h.

[0063] Embodiment 20 includes the method of Embodiment 16, wherein the compound is exposed to visible light at least about 1.2 million Lux*h, but not exceeding about 500 W*h / m2 of ultraviolet light.

[0064] Reference number list 100 filters 102 First Planar Structure 104 First baffle 106 Second baffle 108 First through-opening 110 Second through-opening 150 First edge 152 Second edge 200 Lightstable Chamber 202 Light source 204 Sample Platform 206 Top surface 302 Bottom 304 Air Inlet Vent 306 Air outlet vent 308 First chamber side wall 310 Second chamber side wall 312 Irradiation Intensity Sensor 314 Internal thread 316 Support Ledge ETUM External Temperature and UV Meter DC dark contrast S sample

Claims

1. A photostability test chamber (200), a. An internal chamber having a top surface (206), a bottom surface (302), and two opposing side walls (308, 310), b. A light source (202) located on the top surface (206), c. A sample platform (204) positioned above the bottom surface (302), d. A filter (100), i. A first planar structure (102) configured to extend across the horizontal cross-section of the photostable chamber (200), ii. A first baffle (104) spaced apart from the first edge (150) of the first planar structure (102) and extending from the lower surface of the first planar structure (102), iii. A second baffle (106) spaced apart from the second edge (152) of the first planar structure (102) and extending from the lower surface of the first planar structure (102), The first edge (150) and the second edge (152) are opposite edges of the first planar structure (102), and the second baffle (106) is iv. The first through-opening (108) in the first planar structure (102) located between the first edge (150) and the first baffle (104), v. comprising a second through-opening (110) in the first planar structure (102) located between the second edge (152) and the second baffle (106), The filter (100) is configured to be suspended within the photostable chamber (200), and the first planar structure (102) comprises a polymer that limits the transmittance of ultraviolet light to at least 30%. e. The filter (100) is positioned at least 6 cm above the sample platform (204) and below the light source (202), and the filter (100) is supported by internal screws (314) on the two opposing side walls (308, 310), f. Air inlet vent (304) in the first side wall (308), g. comprising an air outlet vent (306) in the second side wall (310), The first baffle (104) of the filter (100) directs the airflow from the air inlet vent (304) Passing through the first through-opening (108), crossing the first planar structure (102), and passing through the second through-opening (110), Furthermore, a photostability test chamber (200) is configured to be located below the filter (100) and directed within the sample area, and out of the air outlet vent (306).

2. The photostability test chamber according to claim 1, wherein the filter (100) is not fixedly attached to the opposing side walls (308, 310).

3. The photostability test chamber according to claim 1, wherein the first baffle (104) and the second baffle (106) help to distribute the airflow above and below the filter (100).

4. The light source (202) emits ultraviolet light and visible light, as described in claim 1, for the photostability test chamber.

5. The photostability test chamber according to claim 1, wherein the sample platform (204) is a metal rack or a metal plate.

6. The photostability test chamber according to claim 1, wherein the filter (100) reaches the sample platform (204) and limits the transmittance of ultraviolet light from the light source to at least 50%.

7. The photostability test chamber according to claim 1, further comprising an irradiation intensity sensor (312).

8. The photostability test chamber according to claim 1, wherein the filter (100) is positioned 20 cm below the light source.

9. The photostability test chamber according to claim 1, wherein the filter (100) is positioned 9 cm to 12 cm above the sample platform (204).

10. A filter for use in a photostability test chamber according to any one of claims 1 to 9, a. A first planar structure (102) configured to extend across the horizontal cross-section of the photostable chamber (200), b. A first baffle (104) spaced apart from the first edge (150) of the first planar structure (102) and extending from the lower surface of the first planar structure (102), c. A second baffle (106) spaced apart from the second edge (152) of the first planar structure (102) and extending from the lower surface of the first planar structure (120), The first edge (150) and the second edge (152) are opposing edges (150, 152) of the first planar structure (102), and the second baffle (106) d. The first through-opening (108) in the first planar structure (102) located between the first edge (150) and the first baffle (104), e. comprising a second through-opening (110) in the first planar structure (102) located between the second edge (152) and the second baffle (106), The filter is configured to be suspended within the photostable chamber (200), and the first planar structure (102) comprises a polymer that limits the transmittance of ultraviolet light to at least 30%.

11. The filter according to claim 10, wherein the first edge (150) and the second edge (152) are parallel.

12. The filter according to claim 10, wherein the polymer limits the transmittance of ultraviolet light to at least 50%.

13. The filter according to claim 10, wherein the first edge (150) further comprises a support ledge (316) extending downward from the first planar structure (102).

14. The filter according to claim 10, wherein the first planar structure (102) has a length of 30 cm to 50 cm and a width of 25 cm to 40 cm.

15. A method of exposing a compound to ultraviolet light and visible light, a. Positioning the compound on the sample platform (204) of the photostability test chamber (200) described in claim 1, b. Exposing the compound to ultraviolet and visible light from a single light source, A method wherein the ultraviolet light and visible light pass through the filter (100) described in claim 10, and the ultraviolet light is filtered out before reaching the compound.

16. The method according to claim 15, wherein the temperature above the filter is maintained at 5°C to 40°C.

17. The compound is at least 200 W*h / m 2 The method according to claim 15, wherein the person is exposed to ultraviolet light.

18. The method according to claim 15, wherein the compound is exposed to visible light at least 1.2 million Lux*h.

19. The compound is exposed to visible light at a rate of at least 1.2 million Lux*h, but at 500 W*h / m². 2 The method according to claim 15, wherein the person is exposed to ultraviolet light not exceeding a certain threshold.

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