Sterilization indicator reading device and method

Abstract

The invention provides a sterilization indicator reading device. The reading device includes a housing including a top portion defining an aperture therethrough. The aperture is sized to at least partially receive a sterilisation indicator therethrough such that the sterilisation indicator is at least partially received within the housing. The reading device further comprises a heating coil, and the heating coil is arranged in the shell. The heating coil is spaced apart from the sterilisation indicator when the sterilisation indicator is inserted into the housing through the aperture. The heating coil is configured to radiatively heat the sterilization indicator. The reading device also includes an air supply unit disposed within the housing and configured to selectively supply air to the heating coil.

Description

Technical Field

[0001] The present disclosure generally relates to a sterilization indicator reading device and a method for incubating a sterilization indicator. Background Art

[0002] In various industries such as the healthcare industry and other industrial applications, it may be necessary to monitor the effectiveness of the process used to sterilize equipment such as medical devices, instruments, and other disposable and non-disposable products. A sterilization cycle is generally defined as a process that completely destroys all viable sources of biological activity such as microorganisms, including structures such as viruses and spores. As a standard practice, hospitals or other institutions will add sterilization indicators to a batch of products to test the lethality of the sterilization cycle / process. Both biological sterilization indicators and chemical sterilization indicators can be used.

[0003] A biological sterilization indicator may include a known amount of a test microorganism, such as Geobacillus stearothermophilus (formerly known as Bacillus stearothermophilus) or Bacillus atrophaeus (formerly known as Bacillus subtilis) spores, which may be many times more resistant to a particular sterilization process than other contaminating organisms. After the indicator is exposed to the sterilization process, the source of biological activity (e.g., spores) may be incubated in a liquid nutrient medium to determine the effectiveness of the sterilization process, e.g., whether any source survived the sterilization process, source metabolism and / or growth indicating that the sterilization process may not be sufficient to destroy all sources of biological activity.

[0004] Reading devices can be used to read the biological sterilization indicator after the biological sterilization indicator has been subjected to a sterilization process to determine the effectiveness of the sterilization process, that is, whether the sterilization process is able to effectively destroy the test microorganisms of the biological sterilization indicator. However, conventional reading devices may be slow to read the biological sterilization indicator, resulting in a delay in obtaining results indicating the effectiveness of the sterilization process. Summary of the invention

[0005] In a first aspect, the present disclosure provides a sterilization indicator reading device for use with a sterilization indicator having spores and a substance that has a fluorescent response to the concentration of the spores. The sterilization indicator reading device includes a housing, the housing including a top portion and a bottom portion opposite to the top portion. The top portion defines a hole passing therethrough. The size of the hole is designed to at least partially receive the sterilization indicator passing therethrough, so that the sterilization indicator is at least partially received in the housing. The sterilization indicator reading device also includes a heating coil, which is arranged in the housing between the top portion and the bottom portion. The heating coil is at least partially aligned with the hole and defines an internal volume in the heating coil. When the sterilization indicator is inserted into the housing through the hole, the sterilization indicator is at least partially received in the internal volume of the heating coil. The size of the heating coil is designed so that when the sterilization indicator is at least partially received in the internal volume of the heating coil, the heating coil is spaced apart from the sterilization indicator, and the heating coil is configured to radiantly heat the sterilization indicator. The heating coil is configured to switch between an on state and an off state. In the on state, the heating coil is heated. In the off state, the heating coil is not heated. The sterilization indicator reading device also includes an air supply unit, which is arranged in the housing and is configured to selectively supply air to the heating coil. The air supply unit is configured to switch between an activated state and an inactivated state. In the activated state, the air supply unit supplies air to the heating coil. In the inactivated state, the air supply unit does not supply air to the heating coil.

[0006] In a second aspect, the present disclosure provides a sterilization indicator reading device for use with a sterilization indicator having spores and a substance that has a fluorescent response to the concentration of the spores. The sterilization indicator reading device includes a housing, the housing including a top portion and a bottom portion opposite to the top portion. The top portion defines a hole passing therethrough. The size of the hole is designed to at least partially receive the sterilization indicator passing therethrough, so that the sterilization indicator is at least partially received in the housing. The sterilization indicator reading device also includes a heating coil, which is arranged in the housing between the top portion and the bottom portion. When the sterilization indicator is inserted into the housing through the hole, the sterilization indicator is arranged on the proximal side of the heating coil and is spaced apart from the heating coil, so that the heating coil is configured to radiantly heat the sterilization indicator. The heating coil is configured to switch between an on state and an off state. In the on state, the heating coil is heated. In the off state, the heating coil is not heated. The sterilization indicator reading device also includes an air supply unit, which is arranged in the housing and is configured to selectively supply air to the heating coil. The air supply unit is configured to switch between an activated state and an inactivated state. In the activated state, the air supply unit supplies air to the heating coil. In the inactivated state, the air supply unit does not supply air to the heating coil. The sterilization indicator reading device also includes a processor, which is communicatively coupled to the heating coil and the air supply unit. The processor is configured to control the heating coil and the air supply unit so that during a first time period, the heating coil is in an on state and the temperature of the heating coil rises to a first temperature. During the first time period, the air supply unit is maintained in an inactivated state. The processor is further configured to control the heating coil and the air supply unit so that during a second time period immediately following the first time period, the heating coil is in an on state and the temperature of the heating coil is maintained between a second temperature and a third temperature. During the second time period, the air supply unit is maintained in an activated state so as to maintain the temperature of the heating coil between the second temperature and the third temperature. The processor is further configured to control the heating coil and the air supply unit so that during a third time period immediately following the second time period, the heating coil is maintained in an off state. During the third time period, the air supply unit is maintained in an activated state so as to cool the heating coil.

[0007] In a third aspect, the present disclosure provides a method for incubating a sterilization indicator having spores and a substance that has a fluorescent response to the concentration of the spores. The method includes: inserting the sterilization indicator at least partially through a hole of a housing so that the sterilization indicator is disposed proximal to a heating coil disposed in the housing and spaced apart from the heating coil. The heating coil is configured to radiatively heat the sterilization indicator. The method also includes: during a first time period, by controlling the power supply to the heating coil and the air supply unit via a processor, so that during the first time period, the heating coil is in an on state and the air supply unit is in an inactive state, so as to raise the temperature of the heating coil to a first temperature within the first time period. In the on state, the heating coil is heated. In the inactive state, the air supply unit does not supply air to the heating coil. The method also includes: during a second time period immediately following the first time period, by controlling the power supply to the heating coil and the air supply unit via a processor, so that during the second time period, the heating coil is maintained in an on state and the air supply unit is maintained in an activated state, so as to maintain the temperature of the heating coil between a second temperature and a third temperature during the second time period. In the activated state, the air supply unit supplies air to the sterilization indicator. The method further includes: during a third time period immediately following the second time period, by controlling the power supply to the heating coil and the air supply unit via a processor, so that during the third time period, the heating coil is maintained in a disconnected state and the air supply unit is maintained in an activated state to reduce the temperature of the heating coil. In the disconnected state, the heating coil is not heated.

[0008] The details of one or more examples of the present disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the present disclosure will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The exemplary embodiments disclosed herein may be more completely understood by considering the following detailed description in conjunction with the following drawings. The drawings are not necessarily drawn to scale. The same numerals used in the drawings represent similar components. However, it should be understood that the use of numbers to refer to components in a given figure is not intended to limit the components marked with the same number in another figure.

[0010] Figure 1 is a schematic front perspective view of an exemplary sterilization indicator;

[0011] Figure 2 is a schematic front perspective view of a system including a sterilization indicator reading device having a sterilization indicator received therein according to an embodiment of the present disclosure;

[0012] Figure 3 is a schematic cross-sectional view of a sterilization indicator reading device according to an embodiment of the present disclosure;

[0013] Figure 4 is a graph depicting changes in temperature of a heating coil of a sterilization indicator reading device according to an embodiment of the present disclosure with respect to time;

[0014] Figure 5A is a schematic cross-sectional view of a portion of a sterilization indicator reading device according to another embodiment of the present disclosure;

[0015] Figure 5B is a schematic cross-sectional view of a portion of a sterilization indicator reading device according to another embodiment of the present disclosure;

[0016] Figure 6 is a flow chart depicting various steps of a method according to an embodiment of the present disclosure;

[0017] Figure 7 is an exemplary graph depicting changes in the temperature of the heater coil with respect to time and changes in the temperature of the substance of the sterilization indicator due to the changes in the temperature of the heater coil with respect to time; and

[0018] Figure 8 is an exemplary graph depicting changes in the temperature of a heater coil with respect to time and changes in the temperature of a substance of a sterilization indicator due to changes in the temperature of the heater coil with respect to time. DETAILED DESCRIPTION

[0019] In the following description, reference is made to the accompanying drawings which form a part thereof, and in which various embodiments are shown by way of illustration. It should be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present disclosure. Therefore, the following detailed description should not be construed in a limiting sense.

[0020] In the following disclosure, the following definitions apply.

[0021] As used herein, all numbers should be considered to be modified by the term “about.” As used herein, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably.

[0022] As used herein as a modifier of a property or attribute, unless otherwise specifically defined, the term "substantially" means that the property or attribute would be readily recognized by a skilled artisan but does not require absolute precision or a perfect match (e.g., within + / - 20% for a quantifiable property).

[0023] Unless specifically defined otherwise, the term "substantially" means a high degree of approximation (eg, within + / - 10% for a quantifiable property), but likewise does not require absolute precision or a perfect match.

[0024] Unless specifically defined otherwise, the term "about" means a close approximation (eg, within + / - 5% for a quantifiable property), but again does not require absolute precision or a perfect match.

[0025] Terms such as same, equal, consistent, constant, exact, etc. are to be understood as within the usual tolerances or measurement errors applicable to the particular situation, without requiring absolute precision or a perfect match.

[0026] As used herein, the terms "first" and "second" are used as identifiers. Therefore, such terms should not be interpreted as limiting the present disclosure. The terms "first" and "second" are interchangeable in embodiments of the present disclosure when used in conjunction with features or elements.

[0027] As used herein, when a first material is referred to as being "similar" to a second material, at least 90 weight percent of the first and second materials are identical, and any variation between the first and second materials comprises less than about 10 weight percent of each of the first and second materials.

[0028] As used herein, “at least one of A and B” should be understood to mean “only A, only B, or both A and B”.

[0029] As used herein, the term "processor" refers to a computing device that is coupled to one or more other devices / circuits (e.g., switching circuits, etc.) and can be configured to communicate with such devices / circuits (e.g., to control such devices / circuits). A processor may include any device that performs logical operations. A processor may include a general-purpose processor, a central processing unit, an application-specific integrated circuit (ASIC), a digital signal processor, a field-programmable gate array (FPGA), a digital circuit, an analog circuit, a microcontroller, any other type of controller, or any combination thereof.

[0030] As used herein, the term "communicatively coupled" refers to direct coupling between components and / or indirect coupling between components via one or more intermediate components. Such components and intermediate components may include, but are not limited to, joints, communication paths, components, circuit elements, circuits, functional blocks, and / or devices. As an example of indirect coupling, a signal transmitted from a first component to a second component may be modified by one or more intermediate components by modifying the form, nature, or format of the information in the signal, while one or more elements of the information in the signal are still transmitted in a manner that can be recognized by the second component.

[0031] As used herein, the term "sterilization" generally refers to the process of eliminating all bacteria and other living organisms from the surfaces of instruments, medical devices, implants, and other articles used in sterile surgical procedures. Conventional thermal sterilization processes use pressurized steam. Low-temperature chemical sterilization processes use ethylene oxide, hydrogen peroxide, hydrogen peroxide / plasma, or peracetic acid in liquid or vapor form as sterilizing agents, as well as gamma radiation and electron beam sterilization.

[0032] As used herein, the term "sterilizer" refers to a system or device that can perform a sterilization cycle, ie, a process that completely destroys all viable sources of biological activity, such as microorganisms, including structures such as viruses and spores.

[0033] As used herein, the term "result" refers to a result indicating the effectiveness of a sterilization cycle, which can be determined by a sterilization indicator reading device by reading a sterilization indicator that has undergone a sterilization cycle. The result can be positive or negative. A positive result refers to an unsuccessful sterilization of the sterilization indicator after undergoing a sterilization process. After undergoing a sterilization process, when biological activity is detected in the sterilization indicator (e.g., by detecting unsterilized microorganisms), a positive result can be determined by a sterilization indicator reading device. A negative result refers to a successful sterilization of the sterilization indicator after undergoing a sterilization process. When the presence of biological activity is not detected in the sterilization indicator after undergoing a sterilization process, a negative result can be determined by a sterilization indicator reading device. A negative result indicates effective sterilization. In other words, a negative result indicates that the microorganisms in the sterilization indicator are effectively killed during the sterilization process.

[0034] Various sterilization indicators can be used for different sterilization processes using steam, hydrogen peroxide gas, ethylene oxide, etc. Sterilization indicators can carry biological agents. Sterilization indicators are usually placed in a test package within a load containing the article to be sterilized. The sterilization indicator can indicate that the sterilization was successful when the biological agent has been killed. The biological agent carried by the sterilization indicator is usually a test organism that is many times more resistant to the sterilization process than most organisms that exist due to natural contamination. The biological agent can include microorganisms, such as endospores, bacterial spores, etc.

[0035] Reading devices can be used to read a biological sterilization indicator after the biological sterilization indicator has been subjected to a sterilization process to determine the effectiveness of the sterilization process, i.e., whether the sterilization process was able to effectively destroy the test microorganisms of the biological sterilization indicator. However, conventional reading devices can be slow to read the biological sterilization indicator, resulting in a delay in obtaining results that indicate the effectiveness of the sterilization process. Conventional reading devices can utilize a large heater block that requires a large amount of warm-up time and additional energy when heated.

[0036] The present disclosure provides a sterilization indicator reading device for use with a sterilization indicator, the sterilization indicator having spores and a substance that has a fluorescent response to the concentration of the spores. The sterilization indicator reading device includes a housing, the housing including a top portion and a bottom portion opposite to the top portion. The top portion defines a hole passing therethrough. The size of the hole is designed to at least partially receive the sterilization indicator passing therethrough, so that the sterilization indicator is at least partially received in the housing. The sterilization indicator reading device also includes a heating coil, which is arranged in the housing between the top portion and the bottom portion. The heating coil is at least partially aligned with the hole and defines an internal volume in the heating coil. When the sterilization indicator is inserted into the housing through the hole, the sterilization indicator is at least partially received in the internal volume of the heating coil. The size of the heating coil is designed so that when the sterilization indicator is at least partially received in the internal volume of the heating coil, the heating coil is spaced apart from the sterilization indicator, and the heating coil is configured to radiantly heat the sterilization indicator. The heating coil is configured to switch between an on state and an off state. In the on state, the heating coil is heated. In the disconnected state, the heating coil is not heated. The sterilization indicator reading device also includes an air supply unit, which is arranged in the housing and is configured to selectively supply air to the heating coil. The air supply unit is configured to switch between an activated state and an inactivated state. In the activated state, the air supply unit supplies air to the heating coil. In the inactivated state, the air supply unit does not supply air to the heating coil.

[0037] The sterilization indicator reading device of the present disclosure can be used to quickly and accurately read a sterilization indicator that has undergone a sterilization process to determine the efficacy / effectiveness of the sterilization process. In other words, the sterilization indicator reading device of the present disclosure can reduce the time it takes to obtain a result indicating the effectiveness of the sterilization process (also known as TTR (result time)).

[0038] The heating coils can be heated quickly in an "on-demand" mode, compared to conventional readers that may utilize large heater blocks that require a lot of preheating time and their additional heating energy. The result time of the sterilization indicator reader can be shortened by using a servo control to control the heating coils and / or air supply unit to quickly heat the sterilization indicator from room temperature to its optimal temperature, and maintain the optimal temperature throughout the incubation process.

[0039] Now referring to the accompanying drawings, Figure 1A schematic front perspective view of a sterilization indicator 10 is illustrated. The sterilization indicator 10 is preferably a biological sterilization indicator (e.g., a self-contained biological sterilization indicator). Examples of biological sterilization indicators are known and manufactured by companies such as 3M under the trade name ATTEST, by Steris (Mentor, OH) under the trade name Verify, and by Terragene (Argentina).

[0040] Figure 1 The illustrated sterilization indicator 10 includes a cap 12 , an outer vial 14 , and a growth chamber 16 . Figure 1 The illustrated sterilization indicator 10 also includes a process indicator label 18 and an information label 20 disposed on (eg, adhered to) the cover 12 .

[0041] The process indicator label 18 can indicate whether the sterilization indicator 10 has been exposed to a sterilization process. For example, the process indicator label 18 can be configured to undergo a color change when exposed to a sterilization process. Thus, exposure of the sterilization indicator 10 to the sterilization process can be confirmed by observing the color change in the process indicator label 18. In some examples, a color change of the process indicator label 18 from light pink to brown can indicate that the sterilization indicator 10 has been exposed to a sterilization process.

[0042] The information label 20 may include information related to the sterilization indicator 10, such as a vial number, an experiment number, a sterilization process name, or any other information.

[0043] exist Figure 1 In the illustrated example of FIG. 1 , the sterilization indicator 10 further includes a medium ampoule 22 disposed within the outer vial 14 and having a substance 24, and a spore carrier 28 disposed within the growth chamber 16 and having spores 30. In other words, in FIG. Figure 1 In the illustrated example of the sterilization indicator 10, the substance 24 and the spores 30 are provided. The substance 24 has a fluorescence response to the spore viability (i.e., the ability of the spores 30 to survive a sterilization cycle). In other words, the substance 24 can have a fluorescence response to the viable spore concentration (i.e., the concentration of spores 30 that survived the sterilization cycle). In addition, the reaction between the spores 30 and the substance 24 can cause the substance 24 to emit fluorescence when absorbing electromagnetic radiation (e.g., ultraviolet light).

[0044] The spores 30 may be selected based on the sterilization process used. For example, for a steam sterilization process, Geobacillus stearothermophilus or Bacillus stearothermophilus may be used. For an ethylene oxide sterilization process, Bacillus atrophaeus (formerly known as Bacillus subtilis) may be used. The spores 30 may be resistant to the sterilization process. The spores 30 may include, but are not limited to, Geobacillus stearothermophilus, Bacillus stearothermophilus, Bacillus subtilis, Bacillus satrophaeus, Bacillus megaterium, Bacillus coagulans, Clostridium sporogenes, Bacillus pumilus, or a combination thereof.

[0045] Substance 24 (preferably a liquid) may be a nutrient medium and may generally be selected to induce germination and initial growth of spores 30 (if viable). Substance 24 may include one or more sugars, including but not limited to glucose, fructose, cellobiose, or a combination thereof. Substance 24 may also include salts, including but not limited to potassium chloride, calcium chloride, or a combination thereof. In some embodiments, substance 24 may also include amino acids, including but not limited to methionine, phenylalanine, tryptophan, and the like.

[0046] In one example, the sterilization indicator 10 can include an alpha-glucosidase system that is naturally produced within growing cells of Geobacillus stearothermophilus. The alpha-glucosidase in its active state can be detected by measuring the fluorescence produced by enzymatic hydrolysis of a substance 24 (e.g., a non-fluorescent substrate and 4-methylumbelliferyl-alpha-D-glucoside (MUG)).

[0047] Enzymes and substrates that may be suitable for use in the sterilization indicator 10 are identified in US Pat. Nos. 5,073,488 (Matner et al.), 5,418,167 (Matner et al.), and 5,223,401 (Foltz et al.), the entire disclosures of which are incorporated herein by reference.

[0048] The sterilization indicator 10 may have an internal volume of no greater than 0.8 milliliters (mL), no greater than 0.7 mL, no greater than 0.6 mL, no greater than 0.5 mL, no greater than 0.4 mL, no greater than 0.3 mL, or no greater than 0.2 mL. In some examples, the substance 24 may have a volume of approximately 0.6 mL.

[0049] The sterilization indicator 10 may undergo a sterilization cycle / process in a sterilizer. The spores 30 respond to environmental conditions in the sterilizer. For example, the environmental conditions in the sterilizer may partially or completely destroy the biological activity of the spores 30. The environmental conditions in the sterilizer may correspond to any one of a physical sterilization process, a gas sterilization process, and a liquid sterilization process. In one example, the environmental conditions may include the presence of pressurized steam. In another example, the environmental conditions may include the presence of any one of vaporized hydrogen peroxide and ethylene oxide.

[0050] The medium ampoule 22 may be breakable and separable from the spore carrier 28. That is, the substance 24 may not be in fluid communication with the spores 30 until the medium ampoule 22 is broken, punctured, pierced, crushed, ruptured, etc. To allow the substance 24 to mix with the spores 30, the outer vial 14 may also include an ampoule crusher 26 disposed between the medium ampoule 22 and the spore carrier 28. By pressing the cap 12 toward the spore carrier 28 with an appropriate force, the medium ampoule 22 may be broken, punctured, pierced, crushed, ruptured, etc. via the ampoule crusher 26. Such a process of mixing the substance 24 with the spores 30 may be referred to as activation of the sterilization indicator 10. After undergoing a sterilization cycle / process in a sterilizer, the spores 30 may be exposed to the substance 24 to reproduce through activation of the sterilization indicator 10.

[0051] Figure 2 A schematic front perspective view of a system 100 including a sterilization indicator 10 and a sterilization indicator reading device 110 (hereinafter referred to as “reading device 110 ”) according to an embodiment of the present disclosure is illustrated. The reading device 110 is used together with the sterilization indicator 10 .

[0052] The reading device 110 defines mutually orthogonal X-axis, Y-axis, and Z-axis. The X-axis and Y-axis are in-plane axes of the reading device 110, while the Z-axis is a lateral axis disposed along the height of the reading device 110. In other words, the X-axis and Y-axis are disposed along the plane of the reading device 110, while the Z-axis is perpendicular to the plane of the reading device 110.

[0053] The reading device 110 includes a housing 112 including a top portion 114 and a bottom portion 116 opposite the top portion 114. The housing 112 can be compact and can have an internal volume of no greater than 0.5 liters (L), no greater than 0.4 L, no greater than 0.3 L, or no greater than 0.2 L. The housing 112 can thus be compact while being suitable for use with multiple sterilization indicators 10 at the same time.

[0054] When viewed from top to bottom (i.e., along the Z-axis), the housing 112 is Figure 21 and 12. The housing 112 may have a primary side portion 118 formed along the X-axis and a secondary side portion 120 formed along the Y-axis. The top portion 114 of the housing 112 may be flush with the edge of the primary side portion 118 but may be Figure 2 118 as extending above the plane of the major side portion 118.

[0055] As described above, when viewed from the top to the bottom, the housing 112 has a rounded rectangular cross-section. In other words, the housing 112 has two straight edges and two curved edges. The two straight edges may extend substantially along the X-axis, and the two curved edges may extend partially along the Y-axis.

[0056] The top portion 114 defines an aperture 122 therethrough. The aperture 122 is sized to at least partially receive the sterilization indicator 10 therethrough such that the sterilization indicator 10 is at least partially received within the housing 112.

[0057] The sterilization indicator 10 may be activated prior to being inserted into the housing 112 through the aperture 122. Alternatively, the housing 112 may activate the sterilization indicator 10 when the sterilization indicator 10 is inserted through the aperture 122. The housing 112 and the sterilization indicator 10 may include one or more features, such as a shelf, a protrusion, or a body shape, that allow the sterilization indicator 10 to be keyed relative to the housing 112. As described above, the sterilization indicator 10 has spores 30 (e.g., Figure 1 ) and a substance 24 (such as Figure 1 The spores 30 respond to environmental conditions in the sterilizer (e.g., environmental conditions in the sterilizer may partially or completely destroy the biological activity of the spores 30).

[0058] exist Figure 2 In the exemplary embodiment of the present invention, the hole 122 includes a plurality of holes 122 spaced apart from each other. Figure 2 In the exemplary embodiment of , a plurality of sterilization indicators 10 are received in corresponding holes 122 from a plurality of holes 122. In other words, the reading device 110 can receive a plurality of sterilization indicators 10 through corresponding holes 122. Specifically, in Figure 2 In the illustrated embodiment of , the plurality of holes 122 includes four holes 122 arranged in a linear configuration along the X-axis. However, the plurality of holes 122 may include any number of holes 122 arranged in any suitable configuration.

[0059] exist Figure 2In the exemplary embodiment of the reader 110, the reader 110 also includes a display 124. For each well 122 from the plurality of wells 122, the display 124 can visually convey information to the user, such as the number of minutes remaining, a sterilization indicator pass / fail, or a combination thereof. Each well 122 can have its own display 124 that is independent of another display 124 for another well 122. Figure 2 As shown, the display 124 may include a plurality of displays 124a, 124b, 124c, 124d, one display 124 for each aperture 122. For example, the displays 124a, 124d may be an outer array of display elements corresponding to an outer aperture 122 (closest to the edge of the housing 112) from the plurality of apertures 122. The displays 124b, 124c may be an inner array of display elements corresponding to an inner aperture 122 from the plurality of apertures 122. In at least one embodiment, the thickness of the main side portion 118 may be greater near the inner aperture 122 than the outer aperture 122. In addition, the displays 124b, 124c may be brighter than the displays 124a, 124d.

[0060] Figure 3 A schematic cross-sectional view of the reading device 110 is illustrated.

[0061] The reading device 110 also includes a heating coil 130 disposed within the housing 112 between the top portion 114 and the bottom portion 116. When the sterilization indicator 10 is inserted into the housing 112 through the aperture 122, the sterilization indicator 10 is disposed proximal to and spaced apart from the heating coil 130, such that the heating coil 130 is configured to radiatively heat the sterilization indicator 10. In other words, the heating coil 130 is positioned within the housing 112 such that the sterilization indicator 10 does not contact the heating coil 130 when inserted into the housing 112 through the aperture 122. Thus, the heating coil 130 does not conductively heat the sterilization indicator 10. In contrast, the heating coil 130 is configured to radiatively heat the sterilization indicator 10.

[0062] The heating coil 130 may include any suitable material that can be heated so as to radiantly heat the sterilization indicator 10. The material of the heating coil 130 may be stable at high temperatures. The heating coil 130 may include, for example, a metal alloy such as iron-chromium-aluminum (FeCrAl), copper-nickel (CuNi), copper-manganese (CuMn), etc. Preferably, the heating coil 130 includes nickel-chromium (NiCr). Nickel-chromium has corrosion resistance properties at high temperatures and has a high melting point (about 1,400° C.) and high resistivity. Such properties make nickel-chromium a preferred material for the heating coil 130.

[0063] exist Figure 3In the exemplary embodiment of the present invention, the heating coil 130 is at least partially aligned with the hole 122. The heating coil 130 can be wrapped around a coil axis 139. The coil axis 139 can be at least partially aligned with the hole 122. In some embodiments, the coil axis 139 can be substantially parallel to the Z axis. When the sterilization indicator 10 is inserted into the housing 112, the longitudinal axis of the sterilization indicator 10 can be substantially aligned with the coil axis 139.

[0064] In addition, the heating coil 130 defines an interior volume 131 therein. When the sterilization indicator 10 is inserted into the housing 112 through the hole 122, the sterilization indicator 10 can be at least partially received in the interior volume 131 of the heating coil 130. The size of the heating coil 130 can be designed so that the heating coil 130 is spaced apart from the sterilization indicator 10 when the sterilization indicator 10 is at least partially received in the interior volume 131 of the heating coil 130, and the heating coil 130 is configured to radiatively heat the sterilization indicator 10. The width 130W of the heating coil 130 can be greater than the maximum width 10W of a portion of the sterilization indicator 10 received in the interior volume 131. Therefore, the sterilization indicator 10 can be spaced apart from the heating coil 130 and can not contact the heating coil 130.

[0065] The heating coil 130 is configured to switch between an on state and an off state. In the on state, the heating coil 130 is heated. The on state of the heating coil 130 may refer to a state in which power is supplied to the heating coil 130 so that the heating coil 130 is heated up. For example, in the on state of the heating coil 130, electric power may be supplied to the heating coil 130, causing the temperature of the heating coil 130 to rise due to resistive heating.

[0066] In the disconnected state, the heating coil 130 is not heated. The disconnected state of the heating coil 130 may refer to a state in which power supply to the heating coil 130 is interrupted. Therefore, in the disconnected state, the temperature of the heating coil 130 may be reduced or at the ambient temperature within the housing 112.

[0067] exist Figure 3 In the exemplary embodiment of the present invention, the heating coil 130 includes a plurality of heating coils 130 corresponding to the plurality of holes 122. The plurality of holes 122 and the plurality of heating coils 130 are configured to receive a corresponding plurality of sterilization indicators 10 in a removable manner. Figure 3 As shown, each hole 122 and corresponding heating coil 130 can removably receive the sterilization indicator 10. In some embodiments, a plurality of heating coils 130 corresponding to a plurality of holes 122 can be electrically connected in series with each other.

[0068] Although not illustrated, the plurality of heating coils 130 may be thermally isolated from each other. For example, the reading device 110 may further include an insulating material disposed between adjacent heating coils 130 from the plurality of heating coils 130. In such an example, the reading device 110 may simultaneously incubate a plurality of sterilization indicators 10. In addition, the reading device 110 may simultaneously incubate a plurality of sterilization indicators 10 at temperatures different from each other.

[0069] The reading device 110 further includes an air supply unit 140 disposed in the housing 112. The air supply unit 140 is configured to selectively supply air 141 (by Figure 3 ).

[0070] exist Figure 3 In the exemplary embodiment of the present invention, the air supply unit 140 includes at least one fan 144. In some other embodiments, the air supply unit 140 includes at least one blower (not shown). The air supply unit 140 may also include a motor 142 coupled to the at least one fan 144. The motor 142 may be controlled to adjust the air 141 supplied by the at least one fan 144. In some embodiments, the motor 142 may be a variable speed motor.

[0071] The air supply unit 140 is configured to switch between an activated state and an unactivated state. In the activated state, the air supply unit 140 supplies air 141 to the heating coil 130. The activated state of the air supply unit 140 may refer to a state in which power is supplied to the air supply unit 140 so that the air supply unit 140 supplies air 141 to the heating coil 130. Specifically, in the activated state, power is supplied to drive the motor 142.

[0072] In the inactive state, the air supply unit 140 does not supply air 141 to the heating coil 130. The inactive state of the air supply unit 140 may refer to a state in which the power supply to the air supply unit 140 is interrupted. Specifically, in the inactive state, power is not supplied to the motor 142, so that the motor 142 runs idle. Therefore, in the inactive state, the air supply unit 140 may stop supplying air 141 to the heating coil 130.

[0073] exist Figure 3In the exemplary embodiment of the invention, the air supply unit 140 is configured to supply air 141 to the plurality of heating coils 130. In some other embodiments, the at least one fan 144 may include a plurality of fans 144 corresponding to the plurality of heating coils 130. Each fan 144 from the plurality of fans 144 may be configured to supply air 141 to a corresponding heating coil 130 from the plurality of heating coils 130. Each fan 144 may be individually controlled based on the desired application properties. This configuration may allow the reading device 110 to simultaneously incubate a plurality of sterilization indicators 10 at temperatures different from each other.

[0074] As will be described in more detail below, the heating coil 130 and the air supply unit 140 may be controlled together to control the substance 24 ( Figure 1 Specifically, the heating coil 130 and the air supply unit 140 may be controlled in a closed-loop control system, thereby enabling accurate control of the temperature of the substance 24 of the sterilization indicator 10.

[0075] The reading device 110 may further include a processor 150 (comprising: Figure 3 ). The processor 150 may include one or more microprocessors, microcontrollers, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), etc. The processor 150 may be communicatively coupled to the heating coil 130 and the air supply unit 140. The processor 150 may be configured to control the heating coil 130 and the air supply unit 140. Specifically, the processor 150 may selectively put the heating coil 130 in an on state or an off state. The processor 150 may also control the temperature of the heating coil 130 in the on state. In addition, the processor 150 may selectively put the air supply unit 140 in an activated state or an inactivated state. The processor 150 may further control the air 141 supplied by the air supply unit 140.

[0076] The reading device 110 may further include a power supply 160 coupled to the processor 150 in a communicable manner. The power supply 160 may be electrically connected to the heating coil 130 and the air supply unit 140. The power supply 160 may be configured to selectively supply electricity (i.e., electrical power) to the heating coil 130 and the air supply unit 140. The power supply 160 may be adjustable. That is, the size of the power supplied by the power supply 160 may be adjusted and changed based on the desired requirements. The power supply 160 may be a variable DC power supply or a variable AC power supply. In some embodiments, the power supply 160 may include an autotransformer.

[0077] In the on state of the heating coil 130, the processor 150 may control the power supply 160 to supply power to the heating coil 130. It may be noted that the processor 150 may further control the magnitude of the power supplied to the heating coil 130 in the on state. In the off state of the heating coil 130, the processor 150 may control the power supply 160 not to supply power to the heating coil 130.

[0078] In the activated state of the air supply unit 140, the processor 150 may control the power supply 160 to supply power to the air supply unit 140. It may be noted that the processor 150 may further control the magnitude of the power supplied to the air supply unit 140 in the activated state. In the inactivated state of the air supply unit 140, the processor 150 may control the power supply 160 not to supply power to the air supply unit 140.

[0079] exist Figure 3 In the exemplary embodiment of , the power supply 160 is electrically connected to each of the plurality of heating coils 130. The processor 150 may control the power supply 160 to independently supply power to the plurality of heating coils 130. In addition, although not illustrated, the reading device 110 may include separate power supplies 160 for the air supply unit 140 and the plurality of heating coils 130.

[0080] The reading device 110 may also include a temperature sensor 135 (by Figure 3 ). The temperature sensor 135 may be communicatively coupled to the processor 150. The temperature sensor 135 may be configured to sense the temperature of the heating coil 130. The temperature sensor 135 may be disposed proximal to the heating coil 130. The temperature sensor 135 may include, for example, a thermistor, a resistance temperature detector (RTD), a thermocouple, a diode, etc.

[0081] The processor 150 can be further configured to determine the temperature of the heating coil 130 via the temperature sensor 135. The processor 150 can use the temperature sensor 135 to control the heating coil 130 so that the sterilization indicator 10 can achieve one or more preset temperatures in a closed-loop control system. The one or more preset temperatures can be used for the spores 30 ( Figure 1 The temperature for optimal growth is shown in .

[0082] For illustrative purposes, Figure 3 Only one temperature sensor 135 is shown in FIG. 1 . It may be noted that the reading device 110 may include a plurality of temperature sensors 135 corresponding to the plurality of heating coils 130. Each temperature sensor 135 from the plurality of temperature sensors 135 may be configured to sense the temperature of the corresponding heating coil 130. In addition, the processor 150 may determine the temperature of the plurality of heating coils 130 via the plurality of temperature sensors 135.

[0083] The reading device 110 may further include an excitation source (not shown) configured to excite the substance 24 ( Figure 1 ). The excitation source may be any light source that causes the substance 24 of the sterilization indicator 10 to emit fluorescence. For example, the excitation source may emit ultraviolet (UV) electromagnetic radiation (having a wavelength in the range of 10 nanometers to 400 nanometers, preferably 300 nanometers to 400 nanometers). The reading device 110 may also include a sensor (not shown) configured to sense the fluorescence emitted by the substance 24. The sensor may include a color sensor, an optical sensor, etc. The sensor may generate one or more response signals when sensing the fluorescence emitted by the substance 24. The detection of the fluorescence emitted by the substance 24 may indicate the growth of spores 30 in the substance 24 or a positive result. The processor 150 may determine the fluorescence via the sensor and display the fluorescence via the display 124 ( Figure 2 ) showed a positive result.

[0084] Figure 4 A graph 200 depicting the change in temperature of the heating coil 130 with respect to time is illustrated. Temperature is represented on the ordinate axis (Y-axis) and time is represented on the abscissa axis (X-axis). Graph 200 includes a curve 202 representing the temperature of the heating coil 130 with respect to time. The temperature of the heating coil 130 corresponds to the temperature detected by the temperature sensor 135.

[0085] refer to Figure 3 and Figure 4 , the processor 150 may be configured to control the heating coil 130 and the air supply unit 140 so that within the first time period t1, the heating coil 130 is in an on state and the temperature of the heating coil 130 rises to the first temperature 130T1. During the first time period t1, the air supply unit 140 may be maintained in an inactive state. The processor 150 may control the heating coil 130 based on the temperature determined via the temperature sensor 135 to achieve the first temperature 130T1 of the heating coil 130 within the first time period t1.

[0086] The processor 150 may control the power supply 160 to supply power to the heating coil 130 to maintain the heating coil 130 in an on state during the first time period t1. The processor 150 may also control the power supply 160 not to supply power to the air supply unit 140 to maintain the air supply unit 140 in an inactive state during the first time period t1.

[0087] During the first time period t1, the heating coil 130 may radiantly heat the sterilization indicator 10 to heat the substance 24 ( Figure 1 ) to the temperature of the spores 30 ( Figure 1The relationship between the temperature of the heating coil 130 and the corresponding temperature of the substance 24 may be predetermined. For example, the processor 150 may utilize a lookup table to determine the temperature of the heating coil 130 required to achieve the desired temperature of the substance 24. The relationship between the temperature of the heating coil 130 and the corresponding temperature of the substance 24 may also take into account the thermal inertia of the substance 24.

[0088] The processor 150 may be further configured to control the heating coil 130 and the air supply unit 140 so that during a second time period t2 immediately following the first time period t1, the heating coil 130 is in an on state and the temperature of the heating coil 130 is maintained between the second temperature 130T2 and the third temperature 130T3. During the second time period t2, the air supply unit 140 may be maintained in an activated state so as to maintain the temperature of the heating coil 130 between the second temperature 130T2 and the third temperature 130T3. The second temperature 130T2 is less than the third temperature 130T3. In addition, the third temperature 130T3 is less than the first temperature 130T1.

[0089] As depicted by curve 202 , when the air supply unit 140 switches to the active state at the beginning of the second time period t2 , the temperature of the heating coil 130 may significantly drop from the first temperature 130T1 to a temperature between the second temperature 130T2 and the third temperature 130T3 .

[0090] The processor 150 may be configured to control the heating coil 130 and the air supply unit 140 to maintain the temperature of the heating coil 130 between the second temperature 130T2 and the third temperature 130T3 during the second time period t2 based on the temperature determined via the temperature sensor 135 .

[0091] The processor 150 may control the power supply 160 to supply power to the heating coil 130 and the air supply unit 140 to maintain the heating coil 130 in an on state and the air supply unit 140 in an activated state during the second period t2.

[0092] In some embodiments, the difference between the second temperature 130T2 and the third temperature 130T3 may be less than or equal to 10% of the second temperature 130T2. For example, if the second temperature 130T2 is 55°C, the third temperature 130T3 may be between 60.5°C (55°C+5.5°C) and 49.5°C (55°C-5.5°C). In some embodiments, the difference between the second temperature 130T2 and the third temperature 130T3 may be less than or equal to 5% of the second temperature 130T2.

[0093] Thus, during the second time period t2, the heating coil 130 may radiantly heat the sterilization indicator 10 to heat the substance 24 ( Figure 1The temperature of the spores 30 (shown in Figure 1 The optimal incubation temperature is around ).

[0094] During the second time period t2, the processor 150 may determine the growth of the spores 30 (by detecting the fluorescence by the sensor). The processor 150 may display the information via the display 124 ( Figure 2 ) displays the sterilization result of the sterilization indicator 10. Thereafter, the processor 150 may cool the heating coil 130.

[0095] Specifically, the processor 150 may be further configured to control the heating coil 130 and the air supply unit 140 so that during the third time period T3 immediately following the second time period T2, the heating coil 130 is maintained in a disconnected state. During the third time period T3, the air supply unit 140 may be maintained in an activated state to cool the heating coil 130. The processor 150 may control the power supply 160 not to supply power to the heating coil 130 to maintain the heating coil 130 in a disconnected state during the third time period t3. The processor 150 may control the power supply 160 to supply power to the air supply unit 140 to maintain the air supply unit 140 in an activated state during the third time period t3.

[0096] As depicted by curve 202 , during the third time period t3 , the temperature of the heating coil 130 may drop significantly from between the second temperature 130T2 and the third temperature 130T3 .

[0097] Figure 5A A system 300 including a sterilization indicator 10 and a reading device 110 according to another embodiment of the present disclosure is illustrated. Specifically, Figure 5A A portion of the reading device 110 of the system 300 is illustrated. For illustrative purposes, Figure 5A Some elements of the reading device 110 are not shown.

[0098] System 300 is similar to Figure 3 system 100, wherein like elements are represented by like reference numerals. Figure 3 Compared with the heating coil 130, Figure 5A The heating coil 130 has different configurations.

[0099] Specifically, in Figure 5AIn the exemplary embodiment of the present invention, the heating coil 130 has a U-shape. The coil axis 139 of the heating coil 130 may also have a U-shape. When the sterilization indicator 10 is inserted into the housing 112 through the hole 122, the heating coil 130 may be disposed adjacent to the sterilization indicator 10, such that the sterilization indicator 10 is disposed outside the interior volume 131 of the heating coil 130. In addition, when the sterilization indicator 10 is inserted into the housing 112 through the hole 122, the heating coil 130 may at least partially surround the sterilization indicator 10.

[0100] Figure 5B A system 301 including a sterilization indicator 10 and a reading device 110 according to another embodiment of the present disclosure is illustrated. Specifically, Figure 5B A portion of the reading device 110 of the system 301 is illustrated. For illustrative purposes, Figure 5B Some elements of the reading device 110 are not shown.

[0101] System 301 is substantially similar to Figure 5A system 300, wherein like elements are represented by like reference numerals. Figure 5A Compared with the heating coil 130, Figure 5B The heating coil 130 has different configurations.

[0102] Specifically, in Figure 5B In the exemplary embodiment of , the heating coil 130 includes a plurality of heating coils 130A to 130C spaced apart from each other. The plurality of heating coils 130A to 130C may form a U-shape together. Figure 5B In the exemplary embodiment of the present invention, the coil axis 139 of the heating coil 130A is substantially perpendicular to the coil axis 139 of the heating coil 130B. In addition, the coil axis 139 of the heating coil 130B is substantially perpendicular to the coil axis 139 of the heating coil 130C. In addition, the coil axis 139 of the heating coil 130A is substantially parallel to the coil axis 139 of the heating coil 130C. The plurality of heating coils 130A to 130C may at least partially surround the sterilization indicator 10. The plurality of heating coils 130A to 130C may be electrically connected in series with each other.

[0103] Although in Figure 5BAlthough not illustrated in the figure, the reading device 110 may include a plurality of holes 122. The reading device 110 may also include a plurality of heating coils 130A to 130C corresponding to each of the plurality of holes 122. In addition, in some cases, the plurality of heating coils 130A to 130C corresponding to the plurality of holes 122 may be electrically connected in series with each other. For example, one of the plurality of heating coils 130A to 130C corresponding to one of the plurality of holes 122 may be electrically connected in series with one of the plurality of heating coils 130A to 130C corresponding to an adjacent hole 122 (e.g., an adjacent heating coil).

[0104] Figure 6 A flowchart depicting the various steps of a method 400 for incubating a sterilization indicator having spores and a substance that has a fluorescent response to the concentration of spores according to an embodiment of the present disclosure is illustrated. In some embodiments, the method 400 can be performed by the processor 150 ( Figure 3 ) is implemented as shown in . Figures 1 to 3 The method 400 is further described.

[0105] At step 402, the method 400 includes inserting the sterilization indicator at least partially through the hole through the housing such that the sterilization indicator is disposed proximal to and spaced apart from a heating coil disposed within the housing. The heating coil is configured to radiatively heat the sterilization indicator. For example, the method 400 may include inserting the sterilization indicator 10 at least partially through the hole 122 through the housing 112 such that the sterilization indicator 10 is disposed proximal to and spaced apart from a heating coil 130 disposed within the housing 112.

[0106] At step 404, the method 400 further includes: during the first time period, by controlling the power supply to the heating coil and the air supply unit via the processor, so that during the first time period, the heating coil is in an on state and the air supply unit is in an inactive state, so as to increase the temperature of the heating coil to a first temperature within the first time period. In the on state, the heating coil is heated. In the inactive state, the air supply unit does not supply air to the heating coil.

[0107] For example, method 400 may include: during a first time period t1, by controlling the power supply to the heating coil 130 and the air supply unit 140 via the processor 150, so that during the first time period t1, the heating coil 130 is in an on state and the air supply unit 140 is in an inactive state, so as to increase the temperature of the heating coil 130 to a first temperature 130T1 within the first time period t1.

[0108] At step 406, the method 400 further includes: during a second time period immediately following the first time period, by controlling the power supply to the heating coil and the air supply unit via the processor, so that during the second time period, the heating coil is maintained in an on state and the air supply unit is maintained in an activated state, so as to maintain the temperature of the heating coil between the second temperature and the third temperature during the second time period. In the activated state, the air supply unit supplies air to the sterilization indicator.

[0109] For example, method 400 may include: during a second time period t2 immediately following the first time period t1, controlling the power supply to the heating coil 130 and the air supply unit 140 via the processor 150, so that during the second time period t2, the heating coil 130 is maintained in an on state and the air supply unit 140 is maintained in an activated state, so as to maintain the temperature of the heating coil 130 between the second temperature 130T2 and the third temperature 130T3 during the second time period t2.

[0110] At step 408, the method 400 further includes: during a third time period immediately following the second time period, by controlling the power supply to the heating coil and the air supply unit via the processor, so that during the third time period, the heating coil is maintained in a disconnected state and the air supply unit is maintained in an activated state to reduce the temperature of the heating coil. In the disconnected state, the heating coil is not heated.

[0111] For example, method 400 may include: during a third time period t3 immediately following the second time period t2, controlling the power supply to the heating coil 130 and the air supply unit 140 via the processor 150, so that during the third time period t3, the heating coil 130 is maintained in a disconnected state and the air supply unit 140 is maintained in an activated state to reduce the temperature of the heating coil 130.

[0112] In some embodiments, the method 400 further comprises determining the temperature of the heating coil via a temperature sensor. In some embodiments, the method 400 further comprises controlling the power supply to the heating coil via a processor based on the temperature of the heating coil. In some embodiments, the method 400 further comprises controlling the power supply to the air supply unit via a processor based on the temperature of the heating coil.

[0113] For example, method 400 may include: determining the temperature of the heating coil 130 via the temperature sensor 135; controlling the power supply to the heating coil 130 via the processor 150 based on the temperature of the heating coil 130; and controlling the power supply to the air supply unit 140 via the processor 150 based on the temperature of the heating coil 130.

[0114] The method 400 may allow the sterilization indicator 10 to be quickly heated from room temperature to its optimal temperature and maintained at the optimal temperature throughout the incubation process, thereby shortening the result time of the reading device 110 . Experimental Results

[0115] Experiments were conducted on the reading device 110 of the present disclosure. Figures 1 to 3 , the sterilization indicator 10 is inserted into the housing 112 through the aperture 122 of the reading device 110. The sterilization indicator 10 is activated prior to insertion into the housing 112. The sterilization indicator 10 is incubated by the reading device 110. A thermocouple is inserted into the sterilization indicator 10 to determine the temperature of the substance 24 of the sterilization indicator 10.

[0116] The heater coil 130 used in the experiment was made of nickel-chromium. The air supply unit 160 had an airflow of 23 cubic feet per minute (CFM) at 24 volts. The power supply 160 was an adjustable DC power supply. The experiment was conducted at an ambient temperature of about 23°C. The results were determined and plotted below for further reference Figures 1 to 3 Described on the graph.

[0117] Figure 7 A graph 500 is illustrated that represents temperature (in ° C.) on the ordinate axis (Y-axis) and time (in seconds) on the abscissa axis (X-axis). The graph 500 includes a first curve 502 that depicts the temperature of the heating coil 130 as measured by the temperature sensor 135. The graph 500 also includes a second curve 504 that depicts the temperature of the substance 24 of the sterilization indicator 10.

[0118] The heating coil 130 is supplied with 15 volts, 1.9 amps (ie, 28.5 watts) via the power supply 160, and the air supply unit 140 is maintained in an inactive state during the first time period t1 (about 45 seconds). In this experiment, the optimal incubation temperature of the spores 30 is about 60 degrees.

[0119] As depicted by the first curve 502 , during the first time period t1 , the temperature of the heating coil 130 rises to approximately 87° C. As depicted by the second curve 504 , due to the rise in the temperature of the heating coil 130 , the temperature of the substance 24 rises to approximately 59° C. during the first time period t1 .

[0120] Furthermore, as depicted by the first curve 502, during the second time period t2 (about 170 seconds), the temperature of the heating coil 130 is maintained between about 30° C. and about 25° C. During the second time period t2, the air supply unit 140 is maintained in an activated state, so that during the second time period t2, the temperature of the heating coil 130 is maintained between about 30° C. and about 25° C.

[0121] As depicted by the second curve 504, during the second time period t2, the temperature of the heating coil 130 is maintained between about 25° C. and about 30° C. so that the temperature of the substance 24 is maintained at about 59° C. during the second time period t2. During the second time period t2, the air supply unit 140 is maintained in an activated state to maintain the temperature of the heating coil 130 between about 25° C. and about 30° C. during the second time period t2. During the second time period t2, the growth of the spores 30 is determined.

[0122] As depicted by the first curve 502, the power supply to the heating coil 130 is interrupted during the third time interval t3. During the third time period t3, the air supply unit 140 is maintained in an activated state to cool the heating coil 130.

[0123] Figure 8 A graph 600 is illustrated which represents temperature (in ° C.) on the ordinate axis (Y-axis) and time (in seconds) on the abscissa axis (X-axis). The left Y-axis represents the temperature of the substance 24 of the sterilization indicator 10, while the right Y-axis represents the temperature of the heating coil 130 measured by the temperature sensor 135. The graph 600 includes a first curve 602 depicting the temperature of the heating coil 130 as measured by the temperature sensor 135. The graph 600 also includes a second curve 604 depicting the temperature of the substance 24 of the sterilization indicator 10.

[0124] 60 watts are supplied to the heating coil 130 via the power supply 160, and the air supply unit 140 is maintained in an inactive state during the first time period t1 (about 40 seconds). In this experiment, the optimal incubation temperature of the spores 30 is about 60 degrees.

[0125] As depicted by the first curve 602 , during the first time period t1 , the temperature of the heating coil 130 rises to approximately 96° C. As depicted by the second curve 604 , due to the rise in the temperature of the heating coil 130 , during the first time period t1 , the temperature of the substance 24 rises to approximately 63° C.

[0126] Furthermore, as depicted by the first curve 602, during the second time period t2 (about 190 seconds), the temperature of the heating coil 130 is maintained between about 50° C. and about 60° C. During the second time period t2, the air supply unit 140 is maintained in an activated state, so that during the second time period t2, the temperature of the heating coil 130 is maintained between about 50° C. and about 60° C.

[0127] As depicted by the second curve 604, during the second time period t2, the temperature of the heating coil 130 is maintained between about 50° C. and about 50° C. so that the temperature of the substance 24 is maintained at about 60° C. during the second time period t2. During the second time period t2, the air supply unit 140 is maintained in an activated state to maintain the temperature of the heating coil 130 between about 50° C. and about 60° C. during the second time period t2. During the second time period t2, the growth of the spores 30 is determined.

[0128] As depicted by the first curve 602, the power supply to the heating coil 130 is interrupted during the third time interval t3. During the third time period t3, the air supply unit 140 is maintained in an activated state to cool the heating coil 130.

[0129] The experiment was repeated multiple times with the autotransformer selected as the power source 160. The voltage and current were adjusted using the autotransformer. The temperature of the substance 24 at 60 seconds and the time it took for the substance 24 to reach 56° C. were observed. The results are provided in Table 1 below.

[0130] In conclusion, the reading device 110 facilitates rapid heating of the sterilization indicator 10 from room temperature to its optimal temperature and maintains the optimal temperature throughout the incubation period, thereby shortening the result time of the reading device 110 .

[0131] Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein.

[0132] Although specific embodiments have been illustrated and described herein, it will be appreciated by those skilled in the art that a variety of alternative and / or equivalent implementations may replace the specific embodiments shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptation or variation of the specific embodiments discussed herein. Therefore, the present disclosure is intended to be limited only by the claims and their equivalents.

Claims

1. A sterilization indicator reading device for use with a sterilization indicator, wherein the sterilization indicator has spores and a substance that has a fluorescent response to the concentration of the spores, the sterilization indicator reading device comprising: a housing including a top portion and a bottom portion opposite the top portion, the top portion defining an aperture therethrough, wherein the aperture is sized to at least partially receive a sterilization indicator therethrough such that the sterilization indicator is at least partially received within the housing; a heating coil disposed within the housing between the top portion and the bottom portion, wherein the heating coil is at least partially aligned with the aperture and defines an internal volume therein, wherein when the sterilization indicator is inserted into the housing through the aperture, the sterilization indicator is at least partially received in the internal volume of the heating coil, wherein the heating coil is sized such that the heating coil is spaced apart from the sterilization indicator when the sterilization indicator is at least partially received in the internal volume of the heating coil, and the heating coil is configured to radiatively heat the sterilization indicator, wherein the heating coil is configured to switch between an on state and an off state, wherein in the on state the heating coil is heated, and wherein in the off state the heating coil is not heated; as well as An air supply unit is disposed in the shell and is configured to selectively supply air to the heating coil, wherein the air supply unit is configured to switch between an activated state and an unactivated state, wherein in the activated state, the air supply unit supplies air to the heating coil, and wherein in the unactivated state, the air supply unit does not supply air to the heating coil.

2. The sterilization indicator reading device of claim 1, wherein the heating coil comprises nickel-chromium.

3. The sterilization indicator reading device according to claim 1, further comprising a processor, the processor being communicatively coupled to the heating coil and the air supply unit, wherein the processor is configured to control the heating coil and the air supply unit so that: During a first time period, the heating coil is in the on state and the temperature of the heating coil rises to a first temperature, wherein during the first time period, the air supply unit is maintained in the inactive state; During a second time period immediately following the first time period, the heating coil is in the on state and the temperature of the heating coil is maintained between a second temperature and a third temperature, wherein during the second time period, the air supply unit is maintained in the activated state so as to maintain the temperature of the heating coil between the second temperature and the third temperature; and During a third time period immediately following the second time period, the heating coil is maintained in the off state, wherein during the third time period, the air supply unit is maintained in the activated state so as to cool the heating coil.

4. The sterilization indicator reading device of claim 3, further comprising a temperature sensor, the temperature sensor being communicatively coupled to the processor and configured to sense a temperature of the heating coil, wherein the processor is further configured to: determining the temperature of the heating coil via the temperature sensor; controlling the heating coil to achieve the first temperature of the heating coil within the first time period based on the temperature determined via the temperature sensor; and Based on the temperature determined via the temperature sensor, the heating coil and the air supply unit are controlled to maintain the temperature of the heating coil between the second temperature and the third temperature during the second period of time. 5 . The sterilization indicator reading device of claim 3 , wherein a difference between the second temperature and the third temperature is less than or equal to 10% of the second temperature.

6. The sterilization indicator reading device according to claim 3, further comprising a power supply, the power supply being communicatively coupled to the processor and being electrically connected to the heating coil and the air supply unit, wherein: In the on state of the heating coil, the processor controls the power supply to supply power to the heating coil; In the disconnected state of the heating coil, the processor controls the power supply not to supply power to the heating coil; In the activated state of the air supply unit, the processor controls the power supply to supply power to the air supply unit; and In the inactive state of the air supply unit, the processor controls the power supply not to supply power to the air supply unit.

7. The sterilization indicator reading device of claim 6, wherein the power source comprises an autotransformer.

8. A sterilization indicator reading device according to claim 1, wherein the hole includes a plurality of holes spaced apart from each other, wherein the heating coil includes a plurality of heating coils corresponding to the plurality of holes, wherein the plurality of holes and the plurality of heating coils are configured to removably receive a corresponding plurality of sterilization indicators, and wherein the air supply unit is configured to supply air to the plurality of heating coils.

9. The sterilization indicator reading device according to claim 1, wherein the air supply unit includes at least one fan.

10. A sterilization indicator reading device for use with a sterilization indicator, the sterilization indicator having spores and a substance having a fluorescent response to the concentration of the spores, the sterilization indicator reading device comprising: a housing including a top portion and a bottom portion opposite the top portion, the top portion defining an aperture therethrough, wherein the aperture is sized to at least partially receive a sterilization indicator therethrough such that the sterilization indicator is at least partially received within the housing; a heating coil disposed within the housing between the top portion and the bottom portion, wherein when the sterilization indicator is inserted through the aperture into the housing, the sterilization indicator is disposed proximal to and spaced apart from the heating coil, such that the heating coil is configured to radiatively heat the sterilization indicator, wherein the heating coil is configured to switch between an on state and an off state, wherein in the on state the heating coil is heated, and wherein in the off state the heating coil is not heated; an air supply unit disposed in the housing and configured to selectively supply air to the heating coil, wherein the air supply unit is configured to switch between an activated state and an inactivated state, wherein in the activated state the air supply unit supplies air to the heating coil, and wherein in the inactivated state the air supply unit does not supply air to the heating coil; as well as a processor communicatively coupled to the heating coil and the air supply unit, wherein the processor is configured to control the heating coil and the air supply unit such that: During a first time period, the heating coil is in the on state and the temperature of the heating coil rises to a first temperature, wherein during the first time period, the air supply unit is maintained in the inactive state; During a second time period immediately following the first time period, the heating coil is in the on state and the temperature of the heating coil is maintained between a second temperature and a third temperature, wherein during the second time period, the air supply unit is maintained in the activated state so as to maintain the temperature of the heating coil between the second temperature and the third temperature; and During a third time period immediately following the second time period, the heating coil is maintained in the off state, wherein during the third time period, the air supply unit is maintained in the activated state so as to cool the heating coil.

11. The sterilization indicator reading device of claim 10, wherein the heating coil comprises nickel-chromium.

12. The sterilization indicator reading device of claim 10, further comprising a temperature sensor, the temperature sensor being communicatively coupled to the processor and configured to sense a temperature of the heating coil, wherein the processor is further configured to: determining the temperature of the heating coil via the temperature sensor; controlling the heating coil to achieve the first temperature of the heating coil within the first time period based on the temperature determined via the temperature sensor; and Based on the temperature determined via the temperature sensor, the heating coil and the air supply unit are controlled to maintain the temperature of the heating coil between the second temperature and the third temperature during the second period of time.

13. The sterilization indicator reading device of claim 10, wherein a difference between the second temperature and the third temperature is less than or equal to 10% of the second temperature.

14. The sterilization indicator reading device according to claim 10, further comprising a power supply, the power supply being communicatively coupled to the processor and being electrically connected to the heating coil and the air supply unit, wherein: In the on state of the heating coil, the processor controls the power supply to supply power to the heating coil; In the disconnected state of the heating coil, the processor controls the power supply not to supply power to the heating coil; In the activated state of the air supply unit, the processor controls the power supply to supply power to the air supply unit; and In the inactive state of the air supply unit, the processor controls the power supply not to supply power to the air supply unit.

15. The sterilization indicator reading device of claim 14, wherein the power source comprises an autotransformer.

16. A sterilization indicator reading device according to claim 10, wherein the heating coil is at least partially aligned with the hole and defines an internal volume in the heating coil, wherein when the sterilization indicator is inserted into the shell through the hole, the sterilization indicator is at least partially received in the internal volume of the heating coil, and wherein the size of the heating coil is designed so that the heating coil is spaced apart from the sterilization indicator when the sterilization indicator is at least partially received in the internal volume of the heating coil.

17. A sterilization indicator reading device according to claim 10, wherein the heating coil defines an internal volume therein, and wherein when the sterilization indicator is inserted into the shell through the hole, the heating coil is arranged adjacent to the sterilization indicator so that the sterilization indicator is arranged outside the internal volume of the heating coil.

18. The sterilization indicator reading device of claim 17, wherein the heating coil comprises a plurality of heating coils, the plurality of heating coils being spaced apart from each other and at least partially surrounding the sterilization indicator.

19. A method for incubating a sterilization indicator having spores and a substance that has a fluorescence response to the concentration of the spores, the method comprising: inserting the sterilization indicator at least partially through the aperture of the housing such that the sterilization indicator is disposed proximal to and spaced apart from a heating coil disposed within the housing, wherein the heating coil is configured to radiatively heat the sterilization indicator; During a first time period, by controlling power supply to the heating coil and the air supply unit via a processor, so that during the first time period, the heating coil is in an on state and the air supply unit is in an inactive state, so as to increase the temperature of the heating coil to a first temperature within the first time period, wherein in the on state, the heating coil is heated, and wherein in the inactive state, the air supply unit does not supply air to the heating coil; During a second time period immediately following the first time period, by controlling the power supply to the heating coil and the air supply unit via the processor, so that during the second time period, the heating coil is maintained in the on state and the air supply unit is maintained in an activated state, so as to maintain the temperature of the heating coil between a second temperature and a third temperature during the second time period, wherein in the activated state, the air supply unit supplies air to the sterilization indicator; as well as during a third time period immediately following the second time period, by controlling, via the processor, power supply to the heating coil and the air supply unit so that during the third time period, the heating coil is maintained in the disconnected state and the air supply unit is maintained in the activated state to reduce the temperature of the heating coil; In the disconnected state, the heating coil is not heated.

20. The method according to claim 19, further comprising: determining the temperature of the heating coil via a temperature sensor; controlling, via the processor, a supply of power to the heating coil based on a temperature of the heating coil; as well as Based on the temperature of the heating coil, power supply to the air supply unit is controlled via the processor.

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