Device for detecting drugs using structural color of photonic crystal

Abstract

The present application relates to a kind of device for detecting drug using the structural color of photonic crystal, the device includes: shell, the shell is sealed and is arranged to form darkroom;One side of the shell is provided with the through-hole for the insertion of capillary chip, and the capillary chip is provided with photonic crystal;Bearing plate, fixedly arranged in the shell, the bearing plate is provided with the pipe groove for bearing the capillary chip;Camera device, set on the pipe groove of the bearing plate, for shooting photonic crystal image;Control mainboard, connected with the camera device, for controlling the shooting of the camera device.The present application uses the matching of photonic crystal and the body fluid to be measured to quickly detect whether the body fluid to be measured contains drug substance, facilitate on-site law enforcement, improve law enforcement efficiency.

Description

Technical Field

[0001] This invention relates to a device for detecting drugs using the structural color of photonic crystals, and belongs to the field of drug detection technology. Background Technology

[0002] Drug abuse has become a global problem. In recent years, due to socio-economic and scientific and technological development, the types and methods of drug transmission have become more diversified. Current detection methods mainly include gas chromatography-mass spectrometry (GC-MS), high-performance liquid chromatography-mass spectrometry (HPLC-MS), nuclear magnetic resonance (NMR), and capillary electrophoresis. Among these, GC-MS, HPLC-MS, and NMR all require large instruments and relatively standardized external conditions, making them difficult to implement in field testing. Capillary electrophoresis has the advantages of low detection limits and miniaturization, leading to its rapid development and application in enantiomeric separation. However, capillary electrophoresis separation requires the use of certain labels (fluorescent labels) and a series of auxiliary compounds, such as the necessary electrolyte, chiral recognition ligands for chiral recognition, standard substances for quantitative detection and calibration, and fluorescent labels. Its detection is usually based on laser-induced fluorescence, which is costly.

[0003] On-site detection of amphetamines such as ephedrine, pseudoephedrine, chloroephedrine, methcathinone, and methamphetamine is of great significance for criminal investigations, accurate identification of responding drugs, and inference of drug sources. Currently, some relatively mature detection methods exist for on-site testing, such as colorimetric / chromatographic methods and immunoassays, which can be made into test strips for rapid detection. However, due to the inability to use instruments such as chromatography, mass spectrometry, and fluorescence spectroscopy, the detection specificity is relatively poor. Current on-site detection of amphetamines is easily interfered with by compounds with similar structures, and in particular, achieving stereospecific detection is difficult. Summary of the Invention

[0004] To address the aforementioned problems, the purpose of this invention is to provide a device for detecting drugs using the structural color of a photonic crystal. This device can rapidly detect whether the body fluid being tested contains drug substances by matching the photonic crystal with the fluid being tested, facilitating on-site law enforcement and improving law enforcement efficiency.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a device for detecting drugs using the structural color of a photonic crystal, the device comprising:

[0006] The housing is sealed to form a dark chamber, and a through hole is provided on one side of the housing for inserting a capillary chip. A photonic crystal is disposed inside the capillary chip.

[0007] A support plate is fixedly disposed inside the housing, and the support plate has a groove for supporting the capillary chip;

[0008] A camera device is installed above the slot of the carrier plate for capturing images of the photonic crystal;

[0009] The control motherboard is connected to the camera device and is used to control the camera device's shooting.

[0010] Furthermore, a UV light source is also provided inside the housing, the UV light source is located below the support plate, and the tube groove is provided with an opening for the UV lamp to irradiate.

[0011] Furthermore, the tube and its sides are set to a dark color to provide a stable lighting environment for the camera device to capture images and to prevent external interference.

[0012] Furthermore, the capillary chip is also provided with a buffer solution; during detection, one end of the capillary chip is placed in the body fluid to be tested, and the other end is used to extract the body fluid to be tested. The body fluid to be tested fills the capillary chip and squeezes the buffer solution out of the capillary chip so that the body fluid to be tested can react with the photonic crystal.

[0013] Furthermore, the capillary chips located on both sides of the photonic crystal are provided with shrinkage openings to prevent the photonic crystal from being washed away with the body fluid being tested.

[0014] Furthermore, the device also includes a terminal device that communicates with the control motherboard. The terminal device interacts with the control motherboard to control the camera device to capture images of the photonic crystal within the capillary chip. The terminal device acquires the photonic crystal images captured by the camera device and uploads them to a server for processing to complete drug detection.

[0015] Furthermore, the terminal device acquires the photonic crystal image captured by the camera device and uploads it to the server for processing to complete drug detection. The photonic crystal image processing process includes:

[0016] Image preprocessing is performed to locate the position of the photonic crystal in the image and crop the image so that only the photonic crystal remains in the cropped image;

[0017] Extract the color feature vector of the photonic crystal and perform dimensionality reduction.

[0018] The color feature vectors after dimensionality reduction are transformed, identified, and compared using a support vector machine to complete the identification of drugs in the body fluids to be tested.

[0019] Further, image preprocessing includes:

[0020] Convert the image's RGB color space to the HSV color space;

[0021] Filter the image background in the HSV color space;

[0022] The image is binarized and cropped so that only the photonic crystal remains in the cropped image.

[0023] Furthermore, the camera device includes a camera with an arc-shaped opening to focus the photonic crystal within the capillary chip.

[0024] Furthermore, the camera device also includes an LED light source; the LED light source is located near the camera and is used to provide illumination for the camera's shooting.

[0025] Because the present invention adopts the above technical solution, it has the following characteristics:

[0026] 1. This invention utilizes the matching of photonic crystals with the body fluid to be tested to quickly detect whether the body fluid contains narcotic substances, which facilitates on-site law enforcement and improves law enforcement efficiency.

[0027] 2. This invention utilizes terminal devices to observe and respond to the captured results, which is highly intuitive, fast, and can save law enforcement time.

[0028] 3. The photonic crystal images captured by this invention can be saved or uploaded to the cloud server and automatically compared with standard spectra in historical images, thus shortening the detection time.

[0029] 4. Compared with existing methods for detecting amphetamine-type drugs, such as chromatography, capillary chip electrophoresis, and nuclear magnetic resonance spectroscopy, this invention retains the advantages of low detection limits, high analytical efficiency, and miniaturized detection units of the original methods. On the other hand, it effectively corrects the disadvantages of other methods, such as the need to carry multiple auxiliary substances, complex operation, and the need for large-scale instruments and equipment.

[0030] In summary, this invention can be widely applied to rapid drug detection. Attached Figure Description

[0031] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings:

[0032] Figure 1 This is a schematic diagram of the closed structure of the device according to an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of the internal structure of the device according to an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of the capillary chip structure according to an embodiment of the present invention;

[0035] Figure 4 This is a data processing principle diagram of an embodiment of the present invention;

[0036] The attached diagram is labeled as follows: 1-Housing; 2-Through hole; 3-Capillary chip; 31-Contraction opening; 4-Photonic crystal; 5-Support bracket; 51-Support plate; 6-Camera; 7-Control motherboard; 8-Power supply. Detailed Implementation

[0037] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0038] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "above," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure.

[0039] Photonic crystals are a class of regular structures formed by the periodic arrangement of materials with different refractive indices or dielectric constants. They possess excellent optical properties. When the frequency of light falls within the photonic bandgap range, it cannot propagate within the photonic crystal, forming a photonic bandgap. The structural colors of photonic crystals are generated due to the existence of the photonic bandgap. When the bandgap range falls within the visible light range, visible light of specific frequencies cannot pass through the crystal. This non-propagating light is reflected by the photonic crystal, forming coherent diffraction on the surface of the periodically structured crystal. These very narrow wavelengths of light are perceived by the eye, producing brilliant structural colors. Given the increasingly widespread research on photonic crystals and their expanding applications, it is of great significance to utilize this property of photonic crystals and rapidly compare and determine the presence and content of certain narcotic substances for rapid law enforcement.

[0040] Photonic crystals possess a specific spectrum. When not bound to a specific substance, they exhibit coherent diffraction on their periodic crystal surface, allowing a camera to capture images of the photonic crystal with its specific spectrum. When a photonic crystal comes into contact with a specific drug substance, the maximum reflectance spectrum of the photonic crystal shifts, causing a color change. The camera captures the photonic crystal after this color change and compares it with historical images to determine whether the tested bodily fluid contains the drug substance. Furthermore, the degree of shift in the maximum reflectance spectrum and the resulting color change vary depending on the concentration of the drug substance. This allows for the determination of the drug substance's concentration range through image comparison.

[0041] Current on-site detection of amphetamines is easily affected by compounds with similar structures, and it is particularly difficult to achieve stereospecific detection.

[0042] This invention provides a device for detecting drugs using the structural color of photonic crystals. The device includes a housing, which is sealed to form a dark chamber; a through-hole on one side of the housing for inserting a capillary chip containing a photonic crystal; a support plate fixedly disposed within the housing, with grooves on the support plate for supporting the capillary chip; a camera device disposed above the grooves on the support plate for capturing images from the photonic crystal; and a control motherboard connected to the camera device for controlling the camera's imaging capabilities. Therefore, this invention utilizes the matching of a photonic crystal with the body fluid being tested to rapidly detect the presence of drugs in the fluid, facilitating on-site law enforcement and improving enforcement efficiency.

[0043] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0044] like Figures 1-3 As shown, the device for detecting drugs using the structural color of a photonic crystal provided in this embodiment includes a housing 1, which is sealed to form a dark chamber. A through hole 2 is provided on one side of the housing 1 for a capillary chip 3 to pass through. A photonic crystal 4 and a buffer solution are disposed inside the capillary chip 3, with the photonic crystal 4 stored in the buffer solution.

[0045] The housing 1 contains a support bracket 5, a camera 6, an LED light source (not shown in the figure), a control motherboard 7, and a power supply 8. The support bracket 5 is fixedly mounted inside the housing 1. A support plate 51 for supporting the capillary chip 3 is mounted on the top of the support bracket 5, and a slot for supporting the capillary chip 3 is formed on the support plate 51. The camera 6 is positioned above the slot on the support plate 51. The LED light source is located near the camera 6 to provide illumination for the camera's imaging, ensuring clear imaging of the photonic crystal. If the camera 6 itself includes an LED light source, a separate LED light source can be omitted. The control motherboard 7 connects to the LED light source and the camera 6, controlling the switching of the LED light source and the imaging of the camera 6. The power supply 8 can be a battery or an external power source to power the control motherboard 7, the camera 6, and the LED light source. This embodiment uses a battery 8 as an example.

[0046] In a preferred embodiment, the device further includes a terminal device that can communicate with the control motherboard 7 via Bluetooth, Wi-Fi, or USB. The terminal device interacts with the control motherboard 7 to control the camera 6 to capture images of the photonic crystal 4 within the capillary chip 3. The terminal device acquires the photonic crystal images captured by the camera 6 and uploads them to the cloud on the server for comparison with a standard spectrum. The standard spectrum can be, for example, photonic crystal images containing various concentrations of amphetamine-type drugs, thereby determining whether the body fluid being tested contains a certain drug substance and determining the content of that drug substance.

[0047] Furthermore, the process of processing the photonic crystal image includes:

[0048] S1. Image preprocessing to locate the position of the photonic crystal in the image and crop the image so that only the photonic crystal remains in the cropped image, including:

[0049] S11. Convert the original color space of the image to HSV (H hue, S saturation, V luminance) color space to separate color information and luminance information and reduce noise caused by uneven lighting. In this embodiment, the original color space of the image is RGB (R red, G green, B blue) color space.

[0050] Specifically, during the conversion, all pixels in the RGB color space are traversed, and HSV color space conversion is performed on each pixel in the RGB color space:

[0051] V1 = max(R, G, B)

[0052] If V1≠0, S1=(V1-min(R,G,B)) / V1;

[0053] If V1 = 0, S1 = 0;

[0054] If V1 = R, H1 = 60(GB) / (V1 - min(R,G,B)) and H1 < 0, then H = H1 + 360 / 360 * 255, S = 255 * S1, V = V1; if V1 = R, H1 = 60(GB) / (V1 - min(R,G,B)) and H1 ≥ 0, then H = H1 / 360 * 255, S = 255 * S1, V = V1;

[0055] If V1 = G, H1 = 120 + 60(BR) / (V1 - min(R,G,B)) and H1 < 0, then H = H1 + 360 / 360 * 255, S = 255 * S1, V = V1; If V1 = G, H1 = 120 + 60(BR) / (V1 - min(R,G,B)) and H1 ≥ 0, then H = H1 / 360 * 255, S = 255 * S1, V = V1;

[0056] If V1 = B, H1 = 240 + 60(RG) / (V1 - min(R,G,B)) and H1 < 0, then H = H1 + 360 / 360 * 255, S = 255 * S1, V = V1; if V1 = B, H1 = 240 + 60(RG) / (V1 - min(R,G,B)) and H1 ≥ 0, then H = H1 / 360 * 255, S = 255 * S1, V = V1;

[0057] If R = G = B, H1 = 0; H = H1 = 0, S = 255 * S1, V = V1;

[0058] Furthermore, assuming an image has RGB values ​​of (255, 100, 0), the conversion method described above yields:

[0059] V=V1=max(255,100,0)=255;

[0060] S=S1*255=(V1-min(R,G,B) / V1)*255=((255-0) / 255)*255=255;

[0061] H=H1 / 360*255=60(GB) / (V1-min(R,G,B)) / 360*255=60(100-0) / (255-0) / 360*255=17;

[0062] It can be seen that the RGB value of a certain pixel in the image is (255, 100, 0), and after color space conversion, the HSV value is (17, 255, 255).

[0063] S12. Filter the image background in the HSV color space by filtering a portion of the background using a fixed threshold to facilitate image binarization or image cropping, including:

[0064] The process of traversing the pixels of the HSV color space and filtering the background is as follows:

[0065] If (Hmin,Smin,Vmin)≤(H,S,V)≤(Hmax,Smax,Vmax);

[0066] Then: (H,S,V)=(H,S,V);

[0067] If the above conditions are not met, then (H,S,V) = (0,0,0).

[0068] Furthermore, assuming that in this embodiment (Hmin, Smin, Vmin) is (40, 90, 20) and (Hmax, Smax, Vmax) is (120, 255, 255), taking the converted pixel as an example, (17, 255, 255) = (0, 0, 0), and similarly, (150, 255, 255) = (0, 0, 0).

[0069] S13. The image is binarized and the center distance is calculated to obtain the center coordinates of the photonic crystal. The image is then cropped using the center coordinates as the center point so that only the photonic crystal remains in the cropped image.

[0070] S131, Binarization Processing

[0071] Binarization converts non-zero pixels in the HSV color space to 1 and pure black pixels to 0. Pure black pixels are represented as (0,0,0). Binarization is performed according to the following steps:

[0072] If (H,S,V)=(0,0,0), then (H,S,V)=0;

[0073] If (H,S,V)≠(0,0,0), then (H,S,V)=1.

[0074] S132, Center Distance Calculation

[0075] Center distance coordinates (Pxc, Pyc) = (M 10 / M 00 M 01 / M 00 Pxc and Pyc are the x-coordinate and y-coordinate of the center distance, respectively; where M (moment) is calculated using the following formula:

[0076]

[0077] Where p is the value (0 or 1) of the pixel after binarization, Px is the x-coordinate of the pixel, Py is the y-coordinate of the pixel, and M10, M00, and M01 are respectively:

[0078]

[0079]

[0080]

[0081] The center distance coordinate can be regarded as the average of the sum of the x and y coordinates of a pixel, which reflects the distribution of pixels in the region, while the center distance expresses the center position of all pixel distributions.

[0082] S133. Crop the image with the center distance as the center point so that the cropped image only contains the image of the photonic crystal;

[0083] Specifically, during cropping, all pixels p are traversed. If the coordinates of the current pixel are less than or greater than the maximum and minimum coordinates, it is removed; that is, if Px ≥ Pxc... max Or Px≤Pxc min Or Py≥Pyc max Or Py≤Pyc min Then remove it, and you will get the cropped image, i.e., Pxc. min <Px<Pxc max Pyc min <Py<Pyc max If so, then retain, Pxc max To preserve the maximum x-coordinate of a pixel, Pyc mac To preserve the maximum y-coordinate of a pixel.

[0084] Furthermore, taking an image matrix with a target size of h*w'*3, the maximum and minimum coordinates of the x and y axes are calculated, where h is the height of the cropped image and w' is the width of the cropped image. These values ​​are adjusted according to the actual size of the crystal sphere. In this embodiment, h and w' are taken as 100, but are not limited to this. min =Pxc-50;Pxc max =Pxc+50;Pyc min =Pyc-50;Pyc max =Pyc+50.

[0085] S2. Extract the color features of the cropped image and perform dimensionality reduction using Principal Component Analysis (PCA) to reduce the three-dimensional color feature vector to a two-dimensional feature vector, including:

[0086] Color features are extracted using the mean method, where n is the total number of pixels, n = h * w'. The extracted three-dimensional feature vector of color features is:

[0087] ((∑ n H) / n,(∑ n S) / n,(∑ n V) / n)

[0088] Furthermore, assuming there are a total of 2 pixels, the color features extracted by the mean method are (17+18) / 2, (255+255) / 2, (255+255) / 2). In the above, n = h*w', h and w' are taken as 100, n = 100*100, and the color feature vector is the pixel of each color channel divided by n.

[0089] When using principal component analysis for dimensionality reduction, the extracted color feature vectors are multiplied by the dimensionality reduction matrix to obtain two-dimensional dimensionality-reduced feature vectors. Specifically, the dimensionality reduction matrix is ​​first obtained through pre-training, and then the extracted color features are multiplied by the dimensionality reduction matrix to obtain the dimensionality-reduced feature vectors.

[0090] Furthermore, the dimensionality reduction matrix obtained through pre-training includes:

[0091] S21. Calculate the average of all training data: The training data consists of t training images processed through the above steps (after extracting color features using the mean method), resulting in a t*3 training set matrix. The t*3 training set matrix is ​​called `trainset`, and its average value is...

[0092]

[0093] Where t≥b, b is the number of drug types, 3 is the color channel of HSV, and the training set is a dataset (equivalent to a standard spectrum) consisting of historically collected crystal images and corresponding drug type labels for crystal spheres immersed in the images, used to calculate the covariance matrix and pre-compute the hyperplane position.

[0094] S22. Standardize each training data by subtracting the average value.

[0095] S23. Calculate the covariance matrix. Use the Cov formula to calculate a 3x3 covariance matrix from all training data.

[0096] The Cov formula is

[0097] in, Let be the mean of all u and i.

[0098] S24. Calculate the eigenvalues ​​and eigenvectors of the covariance matrix. The three eigenvalues ​​and three corresponding eigenvectors of the matrix correspond to the eigenvalues ​​and eigenvectors of the color channels in the HSV color space, respectively.

[0099] S25. Sort the eigenvalues ​​from largest to smallest. Based on principal component analysis, adjust the coefficient K by the proportion to obtain a 3*K feature matrix. Multiply the t*3 training set matrix by the 3*K feature matrix to obtain a t*K dimension reduction matrix. Project the standardized training data into a new space using the dimension reduction matrix. That is, when a new image is received, the extracted color feature vector of the new image is multiplied by the dimension reduction matrix to obtain a dimension-reduced two-dimensional vector. Thus, the three-dimensional vector of extracted color features is reduced to a two-dimensional vector.

[0100] S3. The position of the relative hyperplane is calculated using a support vector machine, and the position of the relative hyperplane with the standard spectrum is compared and calculated using an identification function. The drug type corresponding to the feature is then identified.

[0101] Specifically, the dimensionality-reduced two-dimensional vector is first transformed by a kernel function, and then its position relative to the hyperplane is calculated and compared with that of a known standard spectrum by an identification function, thereby determining the type of drug in the liquid to be tested.

[0102] The kernel function is the radial basis function kernel:

[0103]

[0104] The recognition function is f dec (x)=(w T (x+b), where w is the normal vector of the hyperplane, t represents the number of samples, and b is a hyperplane constant. Multiple values ​​for w and b can be set, such as w1-w. r Where w1 and b1 can be the normal vector and constant of the hyperplane corresponding to the photonic crystal before it reacts with the drug, and w2 and b2 can be the normal vector and constant of the standard spectrum of methamphetamine after it reacts with the photonic crystal, given that the drug is known to be methamphetamine. Similarly, w3-w r b3-b r It can be ephedrine, amphetamine, or other types. Taking methamphetamine and ephedrine as examples, the dimensionality-reduced two-dimensional vectors of the known standard spectra of methamphetamine and ephedrine (obtained from a pre-collected training set) are optimized by kernel functions and objective functions to obtain the standard classification results, that is, the normal vector and constant of the standard hyperplane.

[0105] Furthermore, the calculation of the relative hyperplane position of the known standard spectrum includes:

[0106] The dimensionality-reduced two-dimensional vectors from the training set (standard spectrum) are first transformed by a kernel function, which is a radial basis function kernel:

[0107]

[0108] After transformation, according to the objective function

[0109]

[0110] Subject to Yi[(wx)+b]≥1-ξ i (i = 1, 2, ..., t)

[0111] In the formula, i represents the sample number, C is the penalty factor, and ξ i >0, ξ i Outlier;

[0112] The optimization yields the optimal solution for the normal vector and constant of the hyperplane, thus achieving the standard classification effect of drugs. Furthermore, the optimization method employs a sequence minimum optimization algorithm.

[0113] In actual testing, newly acquired photonic crystal images (images taken after the test liquid reacts with the photonic crystal, the presence of drugs is unknown) undergo image preprocessing, PCA dimensionality reduction, and kernel function transformation. When using the recognition function for identification, the non-drug standard values ​​w and b are first used for judgment. When f... dec (x) > 0 indicates non-drugs; when f dec When (x)≤0, it contains drugs; then, using other drug standards w and b, we can make judgments respectively, when f dec (x) > 0 represents drug A; when f dec When (x)≤0, it is not drug A; proceed with the judgment accordingly.

[0114] In a preferred embodiment, the photonic crystal image is acquired as follows: The image of the interaction between the test fluid and the photonic crystal can be obtained by capturing the reaction between the photonic crystal and the test fluid in a dark room using a camera device. For example, the photonic crystal can be immersed in a buffer solution within a capillary chip. One end of the capillary chip is placed in the test fluid, and the other end is connected to a syringe to draw out the test fluid. Once the test fluid fills the capillary chip, the buffer solution is squeezed out, allowing the test fluid to react with the photonic crystal. The test fluid is typically saliva, urine, etc. The camera device then takes a picture of the photonic crystal after the reaction with the test fluid within the capillary chip to obtain the photonic crystal image.

[0115] Furthermore, the terminal device can be other portable mobile devices such as mobile phones, tablets, or computers; there are no restrictions, and the choice can be made according to actual needs.

[0116] Furthermore, such as Figure 4As shown, the terminal device can be a mobile phone with a built-in app. The app can communicate with the control motherboard 7 to control the camera to capture images. The app uploads the captured photonic crystal images to the cloud server. The cloud compares the captured photonic crystal images with standard spectra in the cloud's historical image library to determine whether the tested body fluid contains a certain drug substance and the amount of that drug substance. After the cloud completes the comparison, it backs up and stores the comparison results and sends them back to the app. The app can serve as the center for data collection, data analysis, and data sharing, and it also handles user interaction.

[0117] In a preferred embodiment, the color of the tube and the sides of the tube should be set to a relatively dark color such as black to provide a stable lighting environment for the camera 6 to capture images and to prevent external interference.

[0118] In a preferred embodiment, the LED light source may be white light.

[0119] In a preferred embodiment, camera 6 can be a macro camera. If the macro camera has its own LED white light, then a separate LED light source can be omitted, as long as the lighting conditions are met.

[0120] Furthermore, the macro camera can be a 2μm resolution microscope module, and the macro camera has an arc-shaped opening so that the macro camera can focus on the photonic crystal 4 inside the capillary chip 3.

[0121] In a preferred embodiment, the buffer solution can be neutral water. In actual detection, the body fluid to be tested is extracted using the capillary chip 3 (one end of the capillary chip 3 is placed in the body fluid to be tested, and the other end is connected to a syringe to extract the body fluid to be tested). The body fluid to be tested fills the capillary chip 3 and squeezes the buffer solution out of the capillary chip 3 so that the body fluid to be tested can react with the photonic crystal 4.

[0122] In a preferred embodiment, such as Figure 3 As shown, the capillary chips 3 located at both ends of the photonic crystal are provided with constriction openings 31 to prevent the photonic crystal 4 from being washed away with the test fluid. The test fluid is generally saliva, urine, etc. When the test fluid contains drugs, the photonic crystal 4 reacts with the test fluid and develops a color. When the test fluid does not contain drugs, the photonic crystal retains its original color.

[0123] In a preferred embodiment, a UV light source can be provided below the carrier plate 5, and the wavelength of the UV light source can be 365nm. An opening is provided on the tube groove for UV light source irradiation to avoid the inability to distinguish photonic crystals of similar colors under LED light source irradiation. By using UV light source to take pictures, the obtained photonic crystal image can distinguish between bright and dark areas. Then, the images taken by LED light source and UV light source are combined to improve the resolution of photonic crystal image so as to compare with standard spectrum and confirm the content of drugs such as amphetamine in the body fluid to be tested.

[0124] This embodiment also provides a method of using the device for detecting drugs using the structural color of photonic crystals, including:

[0125] S1. Establish a communication connection between the detection device and the mobile phone, which serves as the terminal device.

[0126] S2. Prepare the substance to be tested.

[0127] The photonic crystal 4 is immersed in the buffer solution inside the capillary chip 3. One end of the capillary chip 3 is placed in the body fluid to be tested, and the other end is connected to a syringe to draw out the body fluid to be tested. The body fluid to be tested fills the capillary chip 3 and squeezes the buffer solution out of the capillary chip 3 so that the body fluid to be tested can react with the photonic crystal 4. The body fluid to be tested is generally saliva, urine, etc.

[0128] S3. After inserting the prepared capillary chip 3 into the through hole 2 on one side of the housing 1, control the macro camera to take pictures of the photonic crystal. The user can adjust the capillary chip in the tube groove until the photonic crystal is clearly displayed in the mobile app.

[0129] S4. Use a mobile app to control the camera to take a picture of the photonic crystal 4 (0.5-1.5mm in diameter) inside the capillary chip 3, and send the photonic crystal image information to the cloud on the server.

[0130] S5. The cloud-based server processes the photonic crystal image to automatically determine whether the tested bodily fluid contains a certain drug substance. When the tested bodily fluid contains a drug, the photonic crystal shows a color change; when the tested bodily fluid does not contain a drug, the photonic crystal retains its original color.

[0131] Specifically, a specific substance in the body fluid being tested can be matched with the microcavity of a photonic crystal. The band gap falls within the visible light range, and visible light of a specific frequency cannot pass through the crystal and is reflected by it. This creates coherent diffraction on the periodically structured crystal surface, allowing the camera to capture a photonic crystal with a color-developing effect (the photonic crystal after being combined with a certain drug substance), thus confirming the presence of the detected substance. The cloud compares the acquired photonic crystal image with a large number of images stored in a historical image library. If the maximum reflection spectrum of the photonic crystal shifts, meaning the photonic crystal changes color before being captured by the camera, the image of the color-changed photonic crystal matches an image in the cloud, indicating the presence of a drug substance in the body fluid being tested and determining its concentration. The system then reports that the body fluid being tested contains a drug substance (such as ephedrine, pseudoephedrine, chloroephedrine, methcathinone, methamphetamine, etc.).

[0132] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In the description of this specification, the terms "one embodiment," "furthermore," "preferredly," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments in this specification. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for detecting drugs using the structural color of a photonic crystal, characterized in that, The device includes: The housing is sealed to form a dark chamber. A through-hole is provided on one side of the housing for inserting a capillary chip. A photonic crystal is disposed inside the capillary chip. A buffer solution is also disposed inside the capillary chip. During detection, one end of the capillary chip is placed in the body fluid to be tested, and the other end is used to extract the body fluid. The body fluid fills the capillary chip, forcing the buffer solution out of the capillary chip, allowing the body fluid to react with the photonic crystal. Shrinkage openings are provided on the capillary chip located on both sides of the photonic crystal to prevent the photonic crystal from being washed away by the body fluid. A support plate is fixedly disposed inside the housing, and the support plate has a groove for supporting the capillary chip; A camera device is installed above the slot of the carrier plate for capturing images of the photonic crystal; The control motherboard is connected to the camera device and is used to control the camera device's shooting.

2. The device for detecting drugs using the structural color of a photonic crystal according to claim 1, characterized in that, The housing is also equipped with a UV light source, which is located below the support plate, and the tube groove has an opening for the UV light source to irradiate.

3. The device for detecting drugs using the structural color of a photonic crystal according to claim 1, characterized in that, The tube and its sides are set to a dark color to provide a stable light environment for the camera device to capture images and to prevent external interference.

4. The apparatus for detecting drugs using the structural color of a photonic crystal according to any one of claims 1 to 3, characterized in that, The device also includes a terminal device that communicates with the control motherboard. The terminal device interacts with the control motherboard to control the camera device to capture images of the photonic crystal inside the capillary chip. The terminal device acquires the photonic crystal images captured by the camera device and uploads them to the server for processing to complete the drug detection.

5. The device for detecting drugs using the structural color of a photonic crystal according to claim 4, characterized in that, The terminal device acquires the photonic crystal image captured by the camera device and uploads it to the server for processing to complete drug detection. The photonic crystal image processing process includes: Image preprocessing is performed to locate the position of the photonic crystal in the image and crop the image so that only the photonic crystal remains in the cropped image; Extract the color feature vector of the photonic crystal and perform dimensionality reduction. The color feature vectors after dimensionality reduction are transformed, identified, and compared using a support vector machine to complete the identification of drugs in the body fluids to be tested.

6. The device for detecting drugs using the structural color of a photonic crystal according to claim 5, characterized in that, Image preprocessing includes: Convert the image's RGB color space to the HSV color space; Filter the image background in the HSV color space; The image is binarized and cropped so that only the photonic crystal remains in the cropped image.

7. The device for detecting drugs using the structural color of a photonic crystal according to claim 1, characterized in that, The camera device includes a camera with an arc-shaped opening to focus the photonic crystal within the capillary chip.

8. The apparatus for detecting drugs using the structural color of a photonic crystal according to claim 7, characterized in that, The camera device also includes an LED light source; the LED light source is located near the camera and is used to provide illumination for the camera's shooting.

Images