Designs and methods for reading thermal contrast amplification signals

Abstract

A thermal contrast amplification (TFA) reader includes a light-emitting diode (LED) light source element, a sensor, I / O circuitry, and an opening for receiving the sample. The reader is configured to compare temperature changes in a test area on the sample with temperature changes in a background area surrounding the test area.

Description

Technical Field

[0001] This invention relates to diagnostics, particularly thermal contrast amplification, which can be applied to colorimetric samples, such as lateral flow measurements. Background Technology

[0002] LFA (Lateral Flow Assay, or Lateral Flow Immunoassay, also known as Rapid Diagnostic Test (RDT) or Bioassay) technology is widely used in both laboratory and non-laboratory settings. In a typical test, a liquid sample from the patient is applied to the test strip. The sample reacts with the chemical reagents on the test strip, causing a change in the strip's optical properties. This visual indication can be observed by a person, for example, when using a home pregnancy test.

[0003] Thermal contrast amplification (TCA) is a method applicable to colorimetric lateral flow assays (LFA) and microfluidics (MF) samples to quantify and enhance sensitivity and specificity. In particular, visual readouts such as the color or fluorescence of a detection line (in fluorescence immunoassays) are directly proportional to the incident light. In contrast, the temperature signal in TCA accumulates over time because it is an integral signal generated by heat. While cooling or thermal ablation effects eventually limit signal generation, and heat flow over time in the system can obscure the signal, the integral signal remains highly effective in generating signals that overcome noise. Furthermore, these thermal signals on dry samples are highly stable compared to fluorescence, which typically decays due to photobleaching. Therefore, the core advantage of TCA is its ability to be used for multiple readouts to improve the signal-to-noise ratio of diluted samples.

[0004] LFA and MF are typically accompanied by colorimetric indicators (visible color and density changes). The molecules in LFA (usually gold nanoparticles (GNPs)) interact strongly with visible light, producing color changes that can be detected using thermal contrast. These color changes are caused by variations in the absorption and reflection of incident light. Such tests, especially LFA, are commonly used for the rapid diagnosis of non-critical illnesses such as influenza, streptococcal infections, or COVID-19. While such tests do not require additional equipment for reading, they suffer from low sensitivity and the inability to provide quantitative readings.

[0005] Such samples can be visually read using more sensitive additional markers, such as fluorescent or magnetic particles. However, quality control often reduces manufacturing yield.

[0006] The core concept of TCA is to use light to heat the molecules that are used for colorimetric readings.

[0007] Traditional TCA implementations employ temperature readout based on infrared thermometry. Sensors in such implementations utilize the emissivity changes in long-wave infrared (7µm to approximately 14µm) electromagnetic radiation caused by temperature variations, based on the Stefan-Boltzmann law (commonly known through blackbody radiation). However, this approach is limited by the finite supply, cost, size, and export restrictions of such sensors. While single-pixel infrared detectors can be used, either the sample must be moved by a motor (increasing cost and size while reducing robustness), or an array of such detectors must be used in conjunction with infrared optics (significantly increasing cost). Summary of the Invention

[0008] In one aspect, a thermal contrast amplification detection reader includes: a light-emitting diode (LED) light source element; a sensor; and I / O circuitry and an opening for receiving a sample; wherein the reader is configured to compare a temperature change in a test region on the sample with a temperature change in a background region surrounding the test region.

[0009] Other implementations may include one or more of the following features: 2. The thermal contrast amplification detection reader according to the first aspect, wherein the temperature change of at least one of the test area and the background area is measured by a temperature proxy index.

[0010] 3. The thermal contrast amplification detection reader according to aspect 2, wherein the temperature change of at least one of the test area and the background area is inferred or measured by means of changes in the electrical properties of the sample.

[0011] 4. The thermal contrast amplification detection reader according to aspect 2, wherein the temperature change of at least one of the test area and the background area is measured by voltage change between multiple pairs or groups of points in the sample.

[0012] 5. The thermal contrast amplification detection reader according to aspect 2, wherein the temperature change of at least one of the test area and the background area is measured by the resistance change between multiple pairs or groups of points in the sample.

[0013] 6. The thermal contrast amplification detection reader according to the first aspect, wherein the sample includes an array of electrical contact pins and voltage and / or resistance measuring components.

[0014] 7. The thermal contrast amplification detection reader according to aspect 2, wherein the temperature change of at least one of the test area and the background area is inferred or measured by means of changes in the optical properties of the sample.

[0015] 8. The thermal contrast amplification detection reader according to the second aspect, wherein the temperature change of at least one of the test area and the background area is measured by the change in color or optical density in the sample.

[0016] 9. The thermal contrast amplification detection reader according to the second aspect, wherein the temperature change of at least one of the test area and the background area is measured by a change in luminescence, such as a change in brightness, a change in color, or a change in afterglow duration.

[0017] 10. The thermal contrast amplification detection reader according to the second aspect, wherein the temperature change of at least one of the test area and the background area is measured by fluorescence change or phosphorescence change.

[0018] 11. The thermal contrast amplification detection reader according to the first aspect, wherein the sensor is located outside the LED projection area.

[0019] 12. The thermal contrast amplification detection reader according to the first aspect, wherein the sensor is transparent or reflects thermal contrast detection LED light.

[0020] 13. The thermal contrast amplification detection reader according to the first aspect further includes a reflective coating between the reading component and the TCA-LED light, the reflective coating being configured to reflect the TCA-LED light.

[0021] 14. The thermal contrast amplification detection reader according to the first aspect, wherein the reader component is transparent or reflects TCA-LED light.

[0022] On the other hand, a thermal contrast amplification detection reader includes: a light-emitting diode (LED) light source element; a camera; and a lateral flow assay (LFA) tray, the lateral flow assay tray including input / output (I / O) circuitry and an opening for receiving a test strip; wherein the camera is configured to capture an image of a sample for color measurement and / or fluorescence changes in a test area on the sample and in a background area surrounding the test area.

[0023] On the other hand, a method for reducing component heating in thermal contrast amplification detection readers as shown and described herein is provided.

[0024] In another aspect, a method for reading temperature changes in a sample is provided, which analyzes thermal contrast by heating colorimetric nanoparticles as shown and described herein to detect antigens, drugs, and other molecules as detection targets, said colorimetric nanoparticles being, for example, gold nanoparticles, silver nanoparticles, and carbon nanoparticles. In another aspect, a thermal contrast amplification detection reader includes: a light-emitting diode (LED) light source element; a lateral flow assay (LFA) including I / O circuitry and an opening for receiving a test strip; and a sensor configured to detect and compare temperature changes in a test area on a sample with temperature changes in a background area surrounding the test area.

[0025] The present invention is provided to present a simplified version of the selected concepts, which will be further described in the specific embodiments below. The present invention is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. Attached Figure Description

[0026] Figure 1 A simplified diagram of a conventional implementation of a lateral flow measurement test strip or microfluidic test strip and a TCA readout system using an infrared camera is shown. Figure 2 and Figure 3 An example sample design is shown where TCA light is used to minimize the absorption of the component that converts thermal changes into electrical signals; Figure 4 and Figure 5 An example of a sample design is shown, in which TCA light is used for component reflection to convert thermal changes into electrical signals; Figure 6 and Figure 7 A simplified spatial reading scheme for changes in electrical properties in a reader is shown, as well as a sample reading circuit that uses a (de)multiplexer to reduce the number of components; Figure 8A and Figure 8B It demonstrates how to use simple thermochromic materials, combined with LED lighting and a camera, to spatially read temperature changes; Figures 9A to 9D Examples of the application locations and methods of different layers of luminescent materials, fluorophores, or phosphors are shown; Figure 10A and Figure 10B An example of how to analyze phosphors with an appropriate delay between excitation light absorption and emission light release is shown; Figure 11A and Figure 11B This demonstrates how to perform spectral separation between TCA and optical readout; Figures 12A to 12E Different optical configurations for TCA and optical readout are shown in the same system; and Figure 13A and Figure 13BTwo example methods are shown, in which the components of the alternative reading method can be shielded from TCA light. Specific Implementation Embodiments of the present invention describe a system and method for reading surrogate indicators of temperature change in thermal contrast amplification (TCA) samples using custom samples and a reader.

[0028] TCA light, as used in this paper, refers to light used to generate thermal contrast, typically a laser or a light-emitting diode (LED). TCA-LED is defined as an LED used to generate thermal contrast. The color, power, and size of the LED are selected such that, due to the absorption spectrum of the colorimetric particles, the temperature change generated in the test area is greater than the temperature change in the background area.

[0029] In this article, colorimetric particles that contribute to generating thermal contrast refer to thermal contrast generating particles (TCGPs). TCGPs are traditionally such as gold nanoparticles, silver nanoparticles, or platinum nanoparticles, but can also be based on latex, carbon, or any other molecules that are easily functionalized to form molecular bonds and can absorb visible light.

[0030] In this paper, "reading LED" refers to an optical reading LED (or group of LEDs) used to read surrogate indicators of temperature change. For example, these can be used as excitation light for phosphors and fluorophores. Alternatively, for thermochromic dyes and other color or optical density readings, these LEDs can be used to provide broadband white light for color cameras, or to evaluate color and / or optical density at specific wavelengths by providing narrowband colored light, and in conjunction with monochrome cameras.

[0031] In this paper, the reading component refers to one or more components embedded in the sample that experience temperature changes due to the heating of colorimetric particles in the test area or background material by the TCA-LED. The reading component itself can also be heated by the TCA-LED (component self-heating). If this heat generation is low, it will not pose a problem. If the heat generation is high, design considerations to reduce or eliminate this effect will be discussed.

[0032] In this paper, the reader sensor refers to the part of the reader that interacts with or engages with the sample to read temperature changes as a proxy. The reader sensor itself can be heated by the TCA-LED (sensor self-heating). If the heat generation is low, it will not pose a problem. If the heat generation is high, design considerations to reduce or eliminate this effect will be discussed.

[0033] Embodiments of the present invention describe the reflection or transmission of light. However, these terms can be used broadly. In its simplest form, it can refer to materials such as transparent glass that transmits a broad spectrum of visible light. However, for example, if green light is used, whether from the emission spectrum of a TCA-LED or a fluorophore, a bandpass filter or dichroic filter that transmits green light but blocks blue light can also be considered as transparent. The technical background and implications should be clear from the optical considerations of the design, and some examples will be discussed further below.

[0034] Standard LFAs or microfluidic chips typically consist of a membrane (LFA) through which the sample solution flows (MF). For simplicity, this layer is referred to as a channel (because the membrane itself is a microporous channel). These structures are built on a backing material (referred to as the backing), usually a transparent flexible plastic (Mylar), whose primary essential properties are to prevent sample liquid from dripping from the bottom of the LFA or MF chip and to provide a mechanical support layer. Part of the backing's function is to ensure that the membrane or channel also adheres well to the backing to prevent lateral leakage.

[0035] Figure 1A typical TCA reader design 100 is shown. A typical sample for TCA includes a porous membrane layer (for LFA) or a channel (for MF) through which the sample solution will flow 101. Layer 101 is constructed on top of a backing layer 102, which is typically a transparent plastic or glass layer. A typical colorimetric sample will have one or more test regions 103 with specially coated and treated areas containing immobilized antibodies or similar specific binding molecules for the target analyte. As the solution flows through, the target analyte is captured. Furthermore, upstream of this location, typically in the solution or at a specific location within the sample itself, the sample solution will mix with colorimetric particles (which also act as TCGPs) bound to the antibody or similar binding molecules attached to the target analyte. Thus, after the solution has passed through, a large amount of TCGP bound to the immobilized antibody or similar analyte in the test region remains, resulting in a visible line with a sufficiently high concentration of the target analyte. A control region 104 is similarly designed but is made to directly bind to the TCPP-antibody combination flowing through. Therefore, regardless of the presence of the target analyte, a noticeable color and TCGP accumulation will appear in the control region 104. In TCA, light 105, typically from a laser or LED, is applied to the sample. At least the test region 103 is illuminated, but a better signal can be obtained if the membrane / channel region surrounding the test region 103 is also illuminated. The control region 104 may or may not be illuminated. Upon illumination, combined with the background heating of the membrane / channel 101 there, the TCGP in the test region 103 generates more heat in the test region than in the surrounding membrane / channel region; heating solely from layer 101 is typically white, translucent, or transparent. The generated heat is linearly related to the intensity of the incident TCA light. Neglecting cooling effects and thermal diffusion, the temperature change is the time integral of the generated heat. This time integral further produces a contrast in the resulting temperature. This temperature contrast is the basis of TCA.

[0036] Traditionally, TCA is implemented using a thermal imager 107. This is generally the lowest-cost method because infrared optics used for non-camera IR detectors to obtain a good signal-to-noise ratio in such implementations are quite expensive. Contact methods (e.g., attempts to apply thermocouples or thermistors to these areas) typically have significant drawbacks (e.g., inconsistencies), difficulty in obtaining accurate measurements from the surrounding area for good "contrast" measurements, or the fact that such sensors are heated by the TCA light itself. To date, no other reasonable alternative has been found that can provide a cost-effectiveness and signal-to-noise ratio comparable to that of an economical thermal camera. According to embodiments of the invention, improvements to the sample and a custom reader are further described herein to perform TCA using alternative methods that read temperature or other alternative indicators.

[0037] It should be noted that in different figures, the same or similar elements use the same or similar reference numerals. It should also be understood that the terminology used herein is intended to describe embodiments and is not intended to be limiting. Unless otherwise stated, ordinal numbers (e.g., first, second, third, etc.) are used to distinguish or identify different elements or steps in a group of elements or steps and do not provide a sequence or quantity limitation on the elements or steps in the embodiments. For example, the elements or steps “first,” “second,” and “third” do not necessarily have to appear in that order, and embodiments are not necessarily limited to three elements or steps. It should also be understood that, unless otherwise stated, any terms such as “left,” “right,” “front,” “rear,” “top,” “bottom,” “forward,” “backward,” “clockwise,” “counterclockwise,” “up,” “down,” and other similar terms such as “upper,” “lower,” “rear,” “front,” “vertical,” “horizontal,” “proximal,” “farthest,” “middle,” etc., are for convenience only and are not intended to imply, for example, any particular fixed position, orientation, or direction. It should also be understood that, unless the context clearly specifies otherwise, the singular forms of “a,” “an,” and “described” include the plural meaning.

[0038] It should be understood that when referring to one element as "connected," "coupled," or "attached" to another element, it can mean a direct connection, coupling, or attachment to the other element, or an indirect connection, coupling, or attachment to the other element, in which an intervening element or intermediate element may be present. In contrast, if referring to one element as "directly connected," "directly coupled," or "directly attached" to another element, there is no intervening element. The accompanying drawings illustrating direct connections, couplings, or attachments between elements should also be understood to cover embodiments in which the elements are indirectly connected, coupled, or attached to each other.

[0039] Alternative methods for reading temperature—electrical methods Various implementations of reading temperature surrogate indicators can be employed, which include a comparison between the test area and the area surrounding the test area. Such implementations include utilizing changes in electrical properties caused by temperature variations. In one embodiment, the reader for such samples includes multiple pairs of contact pins (e.g., spring pins) that contact the sample directly or via electrical contact pads built into or deposited on the sample's underside. Circuitry for accurately measuring voltage and resistance is very economical, and many materials and manufacturing methods are well-established.

[0040] It should be understood that any material that generates a certain voltage at a specific temperature can be used without departing from the scope of the invention, such as a thermocouple array that may be cross-linked with a resistor. Similar potential generation methods can also be used.

[0041] Nickel alloy thermocouples, platinum / rhodium alloy thermocouples, tungsten / rhenium alloy thermocouples, and other thermocouple types can also be used, where the contact joints of the two different metals are inside the sample, for example, embedded in the backing layer. The joints from the thermocouple array can span the test area and the surrounding area.

[0042] It's also important to understand that any material whose resistivity is sensitive to temperature can be used. Thermistors are typically made using metal oxides. Carbon-based resistive elements and thin-film elements can also be used. All of these methods are effective. Such materials can be placed in the backing layer of the sample.

[0043] The following discussion covers three typical designs that utilize the temperature dependence of resistance in three materials: indium tin oxide (ITO) coated (and similar transparent coatings) glass and plastic; liquid crystal; and polished silicon.

[0044] ITO films are used in touchscreens and many related technologies. As a coating, ITO films are transparent, and their resistance can be adjusted according to manufacturing parameters. Due to the material's transparency, ITO-coated glass and plastics exhibit very low heat generation from TCA-LEDs, thus enabling more accurate measurement of temperature changes in the test area. In contrast, for translucent or opaque films, any passing TCA-LED light can cause significant heating of the film itself, thereby masking the temperature change signal caused by heating of the test area. Therefore, for LFA or MF, the use of ITO film backing provides high signal contrast. The manufacturing, processing, and treatment of such films are also very mature and cost-effective. Similar conductive films and coatings that do not cause TCA light absorption can be used. Therefore, coatings can be colored as long as they do not cause TCA light absorption.

[0045] Figure 2An example sample design is shown where the TCA light is used to minimize absorption by the component that converts thermal changes into electrical signals. In this embodiment, a relatively standard film / channel 201 is used. The backing 202 can be a transparent plastic or glass substrate. The test area 203, control area 204, and TCA light 205 are also the same as in a typical system. The difference in this embodiment is that the temperature rise through system conduction 206 is measured. The backing 202 is coated with a thin-film conductive layer 207, such as ITO. The heat then propagating downwards at arrow 206 alters the conductivity of layer 207 in a spatially relevant manner. In this embodiment, the thermal conductivity through the film / channel layer 201 and the backing layer 202 is controlled. For example, plastic generally conducts better thermally than glass and is likely a better material for the backing layer 202. For films, their density and material can also affect thermal conductivity. In general, for this embodiment, because the components are often white, translucent or transparent, a large amount of light 208 illuminating areas outside the test area or control area is scattered, reflected or transmitted, and thus no large background thermal signal is generated.

[0046] Another relatively inexpensive material with temperature-dependent physical properties is liquid crystal (LC). LCs exhibit properties similar to liquids and crystals. Furthermore, LCs can exist in a variety of phases, and their optical and electrical properties are generally temperature-dependent. LCs are commonly found in LCD monitors (where electricity can orient LCs to adjust light transmission) and inexpensive forehead bar thermometers (where temperature-sensitive and color-changing LCs are used).

[0047] LC can be designed to have a temperature-dependent resistivity, a property similar to ITO films, which can be used to read temperature. For this type of liquid crystal application, it is desirable for the liquid crystal to remain transparent, without altering its optical density (e.g., in liquid crystal displays) or color (bar thermometers), as this would cause the liquid crystal to be heated by TCA light. If LC does alter its optical properties, it should not do so in a way that increases TCA light absorption, or alternative mitigating factors should be used (e.g., a reflective coating on top of the LC (discussed later)) to block TCA light from reaching the LC. When the LC remains transparent, similar to ITO films, the transparency of the LC also reduces TCA light absorption. Heating of the LC by the LED. Any conductive, temperature-dependent, similarly transparent material can be used as a backing layer if it can provide sufficient mechanical robustness. Specially modified plastics (to have good electrical conductivity and generally also good thermal conductivity) and conductive polymers are widely available. Alternatively, if the mechanical strength of the material itself is insufficient, an additional layer can be added. This layer can be a transparent, non-conductive layer with electrical contact pads that match the contact posts of the reader, and the electrical contact pads will be electrically connected to the liquid crystal or similar material in a manner that allows for spatial reading resistance variations. In its simplest form, these electrical contact pads can simply be through-holes that pass through electrically in the same spatial pattern as the reader's terminals.

[0048] Figure 3 Another example sample design is shown, in which TCA-light is used for component absorption to convert thermal changes into electrical signals. In this embodiment, the film / channel 301, test region 303, control region 304, and TCA light 305 remain the same as in a typical TCA. However, a special backing 302 is used. The backing 302 is either doped 307 or made of specially modified plastics, polymers, or other conductive and optically transparent bulk materials whose conductivity varies with temperature. Figure 2 Implementation method, Figure 3 The implementation also utilizes differential heating between the test area 303 and the surrounding area. The spatial signal in the heat conducted to the backing 302 can thus be measured as different changes in conductivity in space. As previously described, the optical properties of this implementation ensure that most of the light 308 irradiated outside the test or control area is scattered, reflected, or transmitted, thereby preventing the generation of a large background thermal signal.

[0049] exist Figure 2 and Figure 3 In both implementations, a transparent plastic backing and layers (202+207 or 302) would be advantageous. However, as an example, if green TCA light is used, these layers can also be colored as long as the absorption of green light is low. Thus, for example, if these layers transmit green light or selectively reflect green light and transmit the rest of the light, they may appear green when inspected under light. In one embodiment, the backing layer and the doped or film coating do not significantly absorb TCA light because they will become the primary source of heat generation in the system, which would reduce the detection of desired thermal signals from the test area.

[0050] In another embodiment, a reflective conductive material can be used instead of a transparent conductive material. Silicon or germanium, or other semiconductor materials, especially polished materials, are other exemplary materials on which these samples are based.

[0051] Semiconductors are known to have temperature-dependent resistance. In addition, many semiconductors can be polished, which reduces the amount of heat generated by the TCA-LED and actually reflects some of the light back to the test area, thereby increasing the amount of light available for generating thermal contrast.

[0052] Figure 4 The sample design is shown, in which TCA light is reflected away from the component that converts thermal changes into electrical signals. As previously described, the film / channel 401, test area 403, control area 404, and TCA light 405 remain typical. However, the backing 402 used is a reflective conductive material, such as polished silicon. As previously described, spatially different heat generation and the resulting downward thermal conduction 406 to the conductive material are used for reading. However, with Figure 2 and Figure 3 Compared to the previous implementation, light 408 is now transmitted back towards the film / channel 401 and towards the test area 404. This results in significantly enhanced illumination from the same light source, which can be used to generate thermal contrast.

[0053] While polished metal backings can also be used for this purpose, the resistance and resistance variation of such backings are typically much lower than those of semiconductor materials. Therefore, although such polished metal backings can be used, more precise and complex measurement methods, such as four-wire measurement configurations, are usually required in such setups.

[0054] Alternatively, any moderately conductive material of suitable thickness (such that the volume resistivity is in the range of 0.1 Ohms to 1 GOhms when the sample width is measured from edge to edge) can be measured with high precision using moderately costly electronic equipment. If such a material is not, or cannot be, made transparent or highly reflective by polishing, a highly reflective layer can be applied between the film / channel region and a backing made of such a moderately conductive material.

[0055] Figure 5Another sample design is shown, in which the TCA light is reflected away from the component that converts thermal changes into electrical signals. As previously described, the film / channel 501, test area 503, control area 504, and TCA light 505 remain typical. In this embodiment, the backing material 502 can be made of any number of materials, including unpolished silicon (a more economical material than polished silicon); opaque but conductive plastic; a bulk layer made of materials commonly used in thermistors; and so on. One factor in material selection is that the material should be suitable for a highly TCA-reflective coating 507 such that layer 502 is not directly heated by the TCA light, but simply reflects the spatial distribution of temperature through self-thermal conduction 506. The reflective layer 507 can be produced by a variety of techniques, including electroplating or various chemical or vacuum deposition methods. Alternatively, a separate physical layer with a mirror coating, of significant and measurable thickness, can be used, provided that the spatial thermal map is well transmitted through the layer and the conductivity properties of the separate physical layer do not hinder accurate measurement of layer 502.

[0056] exist Figure 4 and Figure 5 In this case, the reflection of light (408 or 508) does not need to be broad-band (spanning the visible spectrum or a wide range beyond it). High reflectivity only for TCA light is sufficient. For example, if the TCA light is blue, a long-pass filter coating that reflects any light within the blue range is also sufficient. In such a case, the 402 or 502 backing material will not be exposed to the TCA light, thus avoiding unwanted background heat and temperature signals.

[0057] Reader for samples of materials with voltage or resistance changes Using thermocouples or thermistor arrays as part of the reader often doesn't work well because heat needs to be continuously and reliably transferred to these temperature sensors. This is much more difficult than achieving reliable electrical contact. Furthermore, the size and fragility of such sensors can also be problematic, and many sensors (such as thermistors) tend to be opaque and absorb TCA-LED light.

[0058] For electrical contacts, several options exist. First, the contact points can be outside the irradiation area, as long as the electrical path of the target resistance change lies between the contact points. Second, since most of these electrical contacts are metallic or coated, they can be made highly reflective, thereby minimizing the absorption of TCA-LED light.

[0059] Figure 6A simplified spatial reading scheme for changes in electrical properties in a reader is illustrated, along with a sample reading circuit using a (de)multiplexer to reduce the number of components. Consider a sample 603 having a test region 604 and a control region 605. An exemplary reader includes a circuit board 601 with electrical contact posts 602, such as spring-loaded leads (not shown). The posts or spring leads contact the bottom surface of the sample 603. Optionally, the bottom surface of the sample 603 may also have metallized contact pads built into the sample. While multiple measurements can be performed, at the most basic level, consider multiple pairs of posts A1-B1, A2-B2, A5-B5, and A6-B6 contacting the background area surrounding the test region 604 without contacting the control region 605. Under TCA light illumination, due to background heating, a measurable but small change in resistance can be expected in the region between A1 and B1 or between A2 and B2. In some cases, this change may not be measurable because the signal magnitude is below the detection limit. Conversely, if the sample contains the target analyte, test area 604 will be hotter, resulting in a greater resistance change between A3 and B3, and between A4 and B4, than seen outside test area 604. For example, during production or quality control, it is possible, but not necessary, to obtain an estimate of the true temperature and temperature change through simple calibration measurements of resistance using alternative temperature measurement methods.

[0060] Design variations for the sample or reader include conductive leads extending from the test area and surrounding area, allowing the contact points to be safely placed outside the TCA-LED illumination range. These leads can be connected to solder points on the edge or bottom surface, or they can be connected through the sample thickness. Although a simple 2-column n-row contact point array is shown for the reader side, any number of arrangements providing spatial sampling of electrical properties can be used without departing from the scope of the invention, where pairs of points can be measured.

[0061] Figure 7Another simplified spatial reading scheme for changes in electrical properties in a reader is shown, along with a sample reading circuit using a (de)multiplexer to reduce the number of components. A test voltage 701 is applied. Electrical signals (voltage or resistance) spanning multiple pairs of pins 702 can be measured using relatively simple circuitry. Since the components used for such measurements are inexpensive, a reader equipped with multiple parallel circuits (not shown) for this measurement is economically viable. However, alternatively, analog multiplexers / demultiplexers 703 and 704, relays, or any number of other methods can be used to reduce the number of circuits used in the measurement while retaining the ability to address individual pins. In its simplest form, for resistance measurements, a high-precision resistor 706 with suitable resistance, a voltmeter 70, or a voltage-to-digital converter possibly equipped with an external amplifier (such as an instrumentation amplifier), along with a stable test voltage 701 and a reference voltage 707, can be used.

[0062] Alternative methods for reading temperature—optical methods In other embodiments, various implementations of reading temperature as a substitute indicator can be employed, utilizing changes in optical properties caused by temperature variations, including a comparison between the test area and the area surrounding the test area. Readers for such samples will be described later, but in their simplest form, such readers comprise a standard camera or a camera equipped with optical filters and LEDs more commonly found in specifications than those used for TCA-LEDs. Some implementations can result in readers that are still cheaper than those based on infrared cameras. Other implementations may have similar costs, but market forces in the smartphone and drone industries, along with ongoing technological advancements, can help reduce future costs or improve the signal-to-noise ratio. Furthermore, given the competitive nature of this field, the likelihood of such cameras relying on a single source is extremely low.

[0063] Thermochromic dyes and liquid crystals (LC) As discussed earlier, thermochromic LCs exhibit a variety of electrical and optical sensitivities to temperature. Thermochromic dyes and LCs change color with temperature. They are also inexpensive. A well-known example is a simple color-changing forehead thermometer. One implementation uses such a strip as a backing for an LFA (thermochromic fluorocarbon array). The color can be easily read using a color camera illuminated with a white LED. Alternatively, a monochrome camera with multiple color-reading LEDs can be used to determine the color. This thermochromic LC can be further modulated by an electric field, depending on its structure, to enhance the color change or alter the color. In other words, an electric field can also be used to help bias the thermochromic LC. One example uses a thermochromic LC with a small temperature range, where the thermochromic LC changes from red to blue. The applied electricity can be used to bias the thermochromic LC such that this temperature range changes according to the ambient temperature. Figure 8AOne example shown uses two rails 801 and 802 with different voltages in the reader, with rails 801 and 802 in contact with the two edges of the thermochromic layer 800 of the sample strip. It is important to note that although the conversion process is from TCA light to heat to color, the time integration characteristics of TCA can help generate a stronger signal.

[0064] Figure 8B One embodiment is shown in which a thermochromic material is combined with an illuminating LED and a camera to spatially read temperature changes. In this embodiment, a relatively standard film / channel 811 is used. The backing 812 can be any amount of material capable of transmitting temperature changes 816 from the film / channel apertures. The test area 813, control area 814, and TCA light 815 are also the same as in a typical system. A different component is a mirrored reflective layer 817 that reflects most of the TCA light 818 back, thereby increasing the effective light intensity for a given LED and collecting optics. Furthermore, this layer 817 prevents the TCA light from heating the thermochromic layer 819. Layer 819 will change color or absorb more light than it reflects depending on temperature. An external light source 820, such as a low-cost white LED (for color cameras) or a flashing LED of a different color (for monochrome cameras), can be used with the camera 821 to obtain a spatial map of temperature changes. Camera 821 may be considered a “conventional” or “standard” camera that operates within the visible spectrum, but different cameras may be used for different spectra if different spectra are used, without departing from the scope of this disclosure.

[0065] Fluorescence thermometry, thermoluminescence, fluorescence thermal imaging Many materials exhibit temperature dependence of emitted light, including brightness, color, and afterglow duration. It is important to note that this is light emitted by the material itself, unlike differential reflection in the case of thermochromic dyes. In this luminescent case, readout LEDs are not required. Instead, the color or intensity of the emitted light is observed. In the following description, luminescent materials can replace phosphors and phosphors.

[0066] Furthermore, many materials exhibit temperature dependence on the light re-emitted upon absorption of excitation light (emitted light). Depending on the timescale and mechanism, these can be termed fluorescence (typically sub-nanosecond re-emission of light) or phosphorescence (microseconds or longer, such as toys that glow in the dark). In these cases, readout-LEDs are used to provide the absorbed "excitation" light for re-emission.

[0067] For fluorescence, since the response time of emitted light is near instantaneous, one method for detecting temperature changes is to detect changes in emitted light intensity. Typically, an increase in temperature of fluorescent molecules leads to a decrease in emitted light and a slight shift in the emission spectrum. It is important to note that this method still differs from commonly used fluorescence immunoassays. First, compared to most fluorescence immunoassays (which require specific readers regardless of the result), the embodiments of this disclosure retain a colorimetric visual component when using fluorescence. Second, compared to methods involving double labeling with antibodies or other complex organic molecules (e.g., gold nanoparticles with attached fluorophores), this disclosure uses a single method. Such double labeling is costly and has low yields with quality control. In contrast, applying fluorophores to sheet-like materials can generally be easily achieved in large batches or over large areas using more physical and chemical-based manufacturing methods, enabling stable quality and high yields. Furthermore, according to embodiments of this disclosure, changes in the fluorescence signal in the sample still depend on the integral signal from heating, which differs from the simple instantaneous and immediate re-emission of absorbed light by the fluorophore. Thus, reading out, or any alternative indicator of heat accumulated over time, has a powerful natural mechanism for generating stronger signals.

[0068] Fluorescence or phosphorescence can be made compatible with the sample through various configurations and variations, such as by applying thin layers, films, or coatings, or by doping the material with fluorophores or phosphors. For example: 1. Channel doping - read from top or bottom. If read from bottom, the underlying layer (backing, etc.) must be transparent to the excitation and emission light of the phosphor or phosphor.

[0069] 2. Backing and Top Coating – A coating of phosphor or fluorophore is applied to the top surface of the backing. Readouts can be made from either the top or bottom. With an LFA, the signal is better from the bottom because the film has point light scattering. If reading from the bottom, an optional first top mirror can be used above the doped layer or the film, and this mirror can further increase the effectively collected TCA light and the light signal read from below.

[0070] 3. Backing Doping – This is similar to the above, but the bulk of the backing layer is doped instead of having a film or coating. Similarly, an optional first top mirror can significantly improve the signal.

[0071] 4. Backing, base coat - similar to the above, but the base coat is applied.

[0072] Figures 9A to 9D Examples of the application locations and methods of different layers of luminescent materials, fluorophores, or phosphors are shown.

[0073] Figure 9AThe diagram illustrates a case where the film or channel 901 on the backing layer 902 is doped with phosphors or phosphors 907. In such a case, the heat 906 generated by the differential absorption of TCA light 905 at the test region 903 or control region 904 will cause a differential change in the fluorescence or phosphorescence through the bulk of the layer 901 due to the dopant 907.

[0074] Figure 9B This illustrates the case where a fluorophore or phosphor is applied on top of a backing. Without the optional reflective layer 918, this method, in some embodiments, can be combined with [other methods] for microfluidic channels, depending on the channel structure. Figure 9A The situation is similar. However, this reflective layer 918 can be used to increase signal strength, simplify the selection of TCA and optical readout colors, although it brings other cost-benefit considerations, such as manufacturing costs, including reduced yield or additional quality control measures. Figure 9B Instead of doping the channel or film layer 911, a doped layer or film 917 is added below the channel or film layer 911. A backing layer 912 is located below. As previously described, TCA light 915 can induce a differential heating mode 916 due to the test region 913 or control region 914. Heat 916 penetrates the sample bulk, affecting the phosphorescent or fluorescent properties of the dopant in 917.

[0075] Figure 9C This illustrates the application of this fluorophore or phosphor to the lower surface of the backing substrate. If a reflective layer 928 is used, the backing 922 need not be transparent. Furthermore, the reflective layer 928 allows for greater flexibility in selecting the electromagnetic spectrum portions used for TCA light, as well as the excitation and emission light from the fluorophore / phosphor. The film / channel layer 921, backing layer 922, test area 923, control area 924, and TCA light 925 remain typical. Heat 926 penetrates the sample bulk, affecting the phosphorescent or fluorescent properties of the dopant in 927.

[0076] Figure 9D This illustrates the case where the fluorophore or phosphor 937 is embedded throughout or most of the thickness of the backing layer 932. If a reflective layer 928 is used, the backing layer 922 does not need to be transparent. The film / channel layer 931, test area 933, control area 934, and TCA light 935 remain typical. Heat 936 penetrates the sample bulk, affecting the phosphorescent or fluorescent properties of the dopant in 937.

[0077] For phosphorescence, due to the time delay between excitation light absorption and emission light release, multiple factors of the emitted light can be analyzed. These factors can include: amplitude; phase or time delay between excitation and emission light; and variations in decay time, emission light shape, and frequency components. Using phosphors with timescales from microseconds to milliseconds, these analyses can be easily performed at various points of the TCA-LED heating in the test area. Control and measurement at this timescale are simple and cost-effective thanks to modern electronic equipment.

[0078] Figure 10A and Figure 10B An example of how to analyze a phosphor with an appropriate delay between excitation light absorption and emission light release is shown. Two example irradiation modes of the phosphor with a delay between excitation light absorption and emission light release, specifically in the range of 1 μs to 100 ms, are illustrated. Figure 10A In this context, the excitation light can be sinusoidally modulated (1001). Figure 10B In this process, the excitation light can be a square pulse 1003. The resulting delayed light is 1002 ( Figure 10A ) or 1004 ( Figure 10B It can perform various parameter analyses, such as the phase shift of the peaks and troughs of sinusoidal modulated light, or the delay from the start or end of the illumination pulse to the peak or trough. Furthermore, it can analyze the amplitude of the emitted light, as well as measurements of distortion, shape, and frequency components. The examples shown and described are exemplary and are not intended to limit the modulation shape of the excitation light or the parameters that can be analyzed from the emitted light. Additionally, while an emission delay on the order of approximately 1 microsecond (μs) to approximately 100 milliseconds (ms) is chosen due to the relative simplicity and cost of the required electronics, other emission delays can also be used to obtain timely measurements of highly dynamic processes such as temperature changes.

[0079] If the TCA-LED light reaches the fluorophore or phosphor, and the read-LED light reaches the TCGP in the test area, additional factors need to be considered. First, it should be noted that the intensity and duration of the light used for reading are typically one or two orders of magnitude lower than those used for TCA. Therefore, even with a broad-absorption TCGP, the contribution of the read-LED to heating will be minimal. Temporal separation is also useful. This can be a very simple scheme, for example, having the TCA-LED light on for a certain duration, then the read-LED on for a certain duration, during which relevant temperature parameters are measured. This cycle can be repeated. However, the biggest concern usually stems from the photobleaching of the fluorophore or phosphor by the TCA-LED. In these cases, using fluorophores and phosphors with excitation and emission spectra far removed from the TCA-LED spectrum, and selecting TCGPs with spectra far removed from the fluorophore / phosphor spectrum, would be desirable.

[0080] If silver nanoparticles are used, blue LEDs are typically used for TCA. For fluorophores or phosphors, yellow excitation, red emission, or longer wavelengths are used.

[0081] For TCA, green LEDs are typically used when employing gold nanoparticles. For larger or specially shaped gold nanoparticles, pale red LEDs can be used. Near-ultraviolet / blue or red / near-infrared phosphors and phosphors are used.

[0082] For black nanoparticles (mostly carbon-based), LEDs of any color can typically be used for TCA irradiation. While more colors can be combined for TCA illumination, the cost of the optics increases as some of the gains in total power decrease. Furthermore, spectral separation limits the extent to which this can be accomplished. Moreover, with such broad-absorption nanoparticles, the TCA-LED color and the fluorescence-Ex / Em color can be selected relatively freely.

[0083] Figure 11A and Figure 11B This demonstrates how to perform spectral separation between TCA and optical readout. Figure 11A and Figure 11B The text describes spectral separation using two practical examples. In the first example, such as... Figure 11A As shown, the TCA-LED spectrum 1101 is amber in the 600 nanometer (nm) range. TCGPs can have a narrower absorption spectrum 1102A within this range, such as large or specially shaped gold nanoparticles; or they can have a broad excitation spectrum 1102B, such as those seen in black (typically carbon-based) nanoparticles. The selected fluorophore or phosphor can have lower excitation wavelengths 1103 and emission wavelengths 1104. For example, blue / green excitation and green / yellow emission fluorophores are quite common. In the case of a broad excitation spectrum 1103 (1102B), the absorption of TCGPs can be reduced because the power and duration used for such measurements can be several orders of magnitude lower than those for TCA light.

[0084] Similarly, as Figure 11BAs shown, the TCA-LED spectrum 1111 is in the 400 nm range and appears bluish. The TCGP can have a narrower absorption spectrum 1112A within this range, such as silver or platinum nanoparticles, or it can have a broad excitation spectrum 1112B, such as those seen in black (typically carbon-based) nanoparticles. The chosen fluorophore or phosphor can have much higher excitation wavelengths 1113 and emission wavelengths 1114. For example, a yellow / red excitation, orange / near-infrared emission fluorophore can be used. In the case of a broad excitation spectrum 1112B, the absorption of the TCGP can be reduced because the power and duration used for such measurements can be several orders of magnitude lower than those of TCA light.

[0085] Example of a reader for a sample of a material with changing optical properties. In various embodiments, example readers include CMOS or CCD cameras. Additional illumination LEDs (readout LEDs) may also be included. For fluorescence or emission, an optical filter selecting a narrower band of the electromagnetic spectrum can be placed in front of the readout LED or camera. Dichroic mirrors can be used to compress or simplify the imaging path.

[0086] Figures 12A to 12E Some possible configurations of the reader are shown: 1. Read from the top. Figure 12A TCA path and read path are separated 2. Read from the top. Figure 12B Merging the TCA path and camera path 3. Read from the top. Figure 12C Merging the TCA path, read-LED path, and camera path 4. Read from the bottom. Figure 12D TCA path and read path are separated 5. Read from the bottom. Figure 12E Reading - LED path and camera path merge The following section discusses some considerations for implementing the method. It should also be noted that, depending on the structure and optical properties of the sample, the "top" and "bottom" sides may be flipped.

[0087] 1. For example Figure 12AAs shown, when the TCA path and readout path 1200 are separated, one or both paths may not be perfectly aligned or orthogonal to the sample 1202A. In this case, due to the increased complexity of the heating process, one design is to project the TCA-LED 1210 perpendicularly to reduce or eliminate non-uniformity of the TCA-LED light 1212 on the sample 1202A. For example, the tilt of the light can cause uneven heat generation, which is more difficult to interpret, and the timely diffusion of heat plays a more significant role, thus requiring careful consideration. Such a design requires more calibration on blank samples and would benefit more from heat generation and flow models as well as data from actual samples. In contrast, reading thermal substitution indices via light can be relatively simple to achieve because these processes are generally linearly related to the light intensity at the time, and any non-uniformity of the excitation light can be more easily corrected by calibration measurements and software. At its simplest, as part of the calibration, normalization is performed only once per pixel. Therefore, angled illumination and imaging can be performed with fewer corrections required.

[0088] 2. For example Figure 12B As shown, in one embodiment, when emitting light, the light emitted from sample 1202B as sample 1202B changes with temperature is the only light used. Therefore, if the wavelength of this emitted light differs from that of the TCA-LED light 1212, the implementation is simple. A dichroic filter is used, and optionally an additional spectral filter is used on the camera for measurement. Furthermore, this can be easily controlled with simple circuitry and software by alternating the heating and measurement periods using the TCA-LED 1210 via strobe or other methods.

[0089] 3. For example Figure 12C As shown, when using fluorescence or phosphorescence for top-side measurements and the TCA-LED is on the same side, two or more dichroic filters can be used. Similarly, spectral separation often provides the simplest solution, although time-domain separation, as previously mentioned, can be used optionally or in combination.

[0090] 4 and 5, such as Figure 12D and 12E As shown, spectral separation is recommended for cases where TCA-LED light passes through the sample, although temporal separation can also be used optionally or in combination. However, if the TCA-LED light does not pass through samples 1202D and 1202E, for example due to a reflective layer in the sample, then spectral and temporal separation are not required, and the problem is greatly simplified from the perspective of sample design and reader design.

[0091] Prevent the read-component or read-sensor (sensor self-heating) from overheating through TCA-LED illumination. For macroscopic materials on the sample, such as thermocouple wires and contacts, or opaque materials (especially those that absorb TCA-LED light at room temperature), considering additional structures to reduce the heat generated by the sensor material itself is beneficial for improving sensitivity. Similarly, if the readout-sensor component absorbs TCA-LED light, it must be similarly protected under certain conditions. The following discussion primarily applies to electrical readouts, but also to optical readouts, particularly temperature readouts based on color, fluorescence, or phosphorescence, where TCA light may actively interfere with the readout if proper wavelength separation is not performed.

[0092] Initially, the following general design principles should be considered: 1. The method is preferred if it can prevent TCA light from reaching any light-absorbing components in the sample or reader, except for the test area and its surrounding background, and does not self-absorb. In its simplest form, the reflective layer is a highly reflective mirror layer directly beneath the channel layer. The lowest-cost option could be polished aluminum foil or mirror-reflective plastic film from hardware stores and model shops. High-end options could utilize high-quality mirrors achieved through more advanced silver plating or dielectric coating methods. Because these layers are thin and / or have high thermal conductivity, they will allow thermal signals to propagate downwards to areas inaccessible to TCA light. Considerations include, for example, cost-effectiveness and quality control.

[0093] 2. Consider an electrical readout sensor scenario with spring-loaded pins. First, these spring-loaded pins tend to be highly reflective. They can be made even more reflective. Furthermore, even if they do heat up, the resistance change of these contacts is already negligible compared to the resistance change of, for example, an ITO film or silicon.

[0094] 3. Alternatively, simple optical techniques can be used, such as confining the TCA light of a projected TCA-LED between the positions of the spring pins.

[0095] Figure 13A and Figure 13B Two example methods are shown, in which the components of the alternative reading method can be shielded from the TCA light.

[0096] exist Figure 13AThe diagram illustrates the significant advantages of a reflective layer. For a general-purpose film / channel 1301 with a test area 1304, a control area 1305, and TCA light 1306, a widely applicable method is to apply a mirror layer 1302 to prevent TCA light from reaching the backing layer 1303. Furthermore, layer 1302 helps to reflect TCA light upwards 1307, including reflection to the test area 1304, thereby increasing the effective light collection efficiency and signal amplitude. It should be noted that layer 1302 only needs to reflect TCA light; therefore, it can also be a bandpass filter, notch filter, long-pass filter, or short-pass filter.

[0097] Furthermore, the LED projection area can be limited, such as Figure 13B As shown. In Figure 13B In this design, sample 1310 can be read using TCA by electrical means. The test area 1311, control area 1312, and part of the surrounding area can be contacted via electrical contact posts 1313 on circuit board 1314. If TCA-LED light 1315 reaches post 1313 and the post absorbs the light, the post will heat up, thus changing the heating mode and electrical properties. However, the TCA-LED can be projected onto the area between the posts, causing a temperature change within sample 1310 and consequently a change in its electrical properties, which can be detected without heating the posts 1313.

[0098] The illustrations of the embodiments described herein are intended to provide a general understanding of the structure of the various embodiments. These illustrations are not intended as a complete description of all elements and features of apparatuses and systems utilizing the structures or methods described herein. Many other embodiments will be apparent to those skilled in the art upon review of the present invention. Other embodiments can be utilized and derived from the invention, allowing structural and logical substitutions and changes to be made without departing from the scope of the invention. Furthermore, the illustrations are merely representative and may not be drawn to scale. Certain scales in the illustrations may be enlarged, while others may be reduced. Therefore, the invention and the accompanying drawings should be considered illustrative rather than restrictive.

[0099] In this document, for convenience, one or more embodiments of the present invention may be individually and / or collectively referred to as the "Invention," but it is not intended to limit the scope of this application to any particular invention or inventive concept. Furthermore, although specific embodiments have been described and illustrated herein, it should be understood that any subsequent arrangements intended to achieve the same or similar purpose may replace the specific embodiments shown. The present invention is intended to cover any and all subsequent adaptive changes or variations of the various embodiments. In retrospect, combinations of the above embodiments, as well as other embodiments not specifically described herein, will be apparent to those skilled in the art.

[0100] An abstract is provided to comply with 37 CFR §1.72(b), and it should be understood that the abstract is not intended to interpret or limit the scope or meaning of the claims. Furthermore, in the specific embodiments described above, features may be combined together or described in a single embodiment for the purpose of simplification. The invention should not be construed as reflecting that the claimed embodiments employ more features than expressly recited in each claim. Rather, as reflected in the following claims, the inventive subject matter may be less than all the features in any of the disclosed embodiments.

[0101] The subject matter disclosed above should be considered illustrative rather than restrictive, and the appended claims are intended to cover all such modifications, alterations, and other embodiments within the true spirit and scope of this invention. Therefore, to the fullest extent permitted by law, the scope of this invention should be determined by the broadest possible interpretation of the following claims and their equivalents, and should not be limited or constrained by the specific embodiments described above.

Claims

1. A thermal contrast amplification detection reader, comprising: Light-emitting diode (LED) light source element; sensor; as well as I / O circuitry and an opening for receiving samples; The reader is configured to compare the temperature change of the test area on the sample with the temperature change of the background area surrounding the test area.

2. The thermal contrast amplification detection reader of claim 1, wherein, Temperature changes in at least one of the test area and the background area are measured using a temperature substitution index.

3. The thermal contrast amplification detection reader of claim 2, wherein, Temperature changes in at least one of the test area and the background area are inferred or measured by changes in the electrical properties of the sample.

4. The thermal contrast amplification detection reader of claim 2, wherein, Temperature changes in at least one of the test area and the background area are measured by voltage changes between multiple pairs or groups of points in the sample.

5. The thermal contrast amplification detection reader of claim 2, wherein, Temperature changes in at least one of the test area and the background area are measured by resistance changes between multiple pairs or groups of points in the sample.

6. The thermal contrast amplification detection reader of claim 1, wherein, The sample includes an array of electrical contact pins and voltage and / or resistance measuring components.

7. The thermal contrast amplification detection reader of claim 2, wherein, Temperature changes in at least one of the test area and the background area are inferred or measured by changes in the optical properties of the sample.

8. The thermal contrast amplification detection reader of claim 2, wherein, Temperature changes in at least one of the test area and the background area are measured by changes in color or optical density in the sample.

9. The thermal contrast amplification detection reader of claim 2, wherein, Temperature changes in at least one of the test area and the background area are measured by changes in light emission, such as changes in brightness, color, or afterglow duration.

10. The thermal contrast amplification detection reader of claim 2, wherein, Temperature changes in at least one of the test area and the background area are measured by fluorescence or phosphorescence changes.

11. The thermal contrast amplification detection reader of claim 1, wherein, The sensor is located outside the LED projection area.

12. The thermal contrast amplification detection reader of claim 1, wherein, The sensor is either transparent or reflects thermal contrast to detect LED light.

13. The thermal contrast amplification detection reader according to claim 1 further includes a reflective coating between the reading component and the TCA-LED light, the reflective coating being configured to reflect the TCA-LED light.

14. The thermal contrast amplification detection reader of claim 1, wherein, The reader components are transparent or reflective of TCA-LED light.

15. A thermal contrast amplification detection reader, comprising: Light-emitting diode (LED) light source element; Camera; as well as Lateral flow measurement (LFA) tray, the lateral flow measurement tray including input / output (I / O) circuitry and an opening for receiving test strips; The camera is configured to capture images of the sample for color measurement and / or fluorescence changes in the test area on the sample and in the background area surrounding the test area.

16. A method for reducing component heating in a thermal contrast amplification detection reader as shown and described herein.

17. A method for reading temperature changes in a sample, the method comprising analyzing thermal contrast by heating colorimetric nanoparticles as shown and described herein to detect antigens, drugs, and other molecules as detection targets, said colorimetric nanoparticles being, for example, gold nanoparticles, silver nanoparticles, and carbon nanoparticles.

18. A thermal contrast amplification detection reader, comprising: Light-emitting diode (LED) light source element; Lateral flow measurement (LFA), which includes I / O circuitry and an opening for receiving a test strip; as well as A sensor configured to detect and compare temperature changes in a test area on a sample with temperature changes in a background area surrounding the test area.

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