CN106525826B - Molecular smart phone rapid test method based on color dominant wavelength and complementary color wavelength - Google Patents

Abstract

A molecular smart phone rapid measurement method based on color dominant wavelength and complementary color wavelength. Smartphone detection program of wavelength and complementary color wavelength, showing the color dominant wavelength or complementary color wavelength corresponding to different solutions. The invention is used for the detection of the color dominant wavelength and the complementary color wavelength of the smart phone for colorimetric analysis, realizes the rapid quantitative detection of biochemical molecules, has the advantages of simple operation, low cost, wide application range, and is suitable for a large number of users and the like.

Description

Molecular Smartphone Fast Measurement Method Based on Color Dominant Wavelength and Complementary Color Wavelength

technical field

The invention relates to a smart phone quick measurement method for colorimetric analysis, in particular, a color-developing product solution obtained by mixing a sample to be tested and a color-developing agent is injected into a clean and transparent reaction vessel, and then placed in a clean and transparent reaction vessel. Taking pictures with a smartphone under the LED surface light source, and calculating the dominant wavelength or complementary wavelength of the color of the solution to be tested through the smartphone detection program, a quantitative detection method for sample-related parameters is realized.

Background technique

With the development of social economy, scientific progress and the improvement of people's living standards, people's requirements for the water quality of drinking water continue to increase. Therefore, it is particularly important to propose a rapid detection method for water quality. There are many indicators for water quality testing. Among them, drinking water mainly considers the impact on human health, and its water quality standards include some physical indicators, chemical indicators and microbial indicators. pH and nitrite concentration are two of the important indicators. Different indicators have different standards. For example, the pH range of the water sample is required to be 6.5~8.5, and the toxicological indicator of nitrite is 1 mg/L. There are different detection methods for testing water quality indicators. The trace components in water are mainly analyzed by water quality testing instruments, which mainly include chromatographic analysis methods, such as gas chromatography, liquid chromatography, high performance liquid chromatography, and ion chromatography. There are also some commonly used methods for indicators, such as spectrophotometry, titration analysis, gravimetric analysis, and electrochemical analysis. Although this type of detection method has relatively accurate detection results, its detection cost is high, it takes a long time, and it requires professional operation.

In recent years, colorimetry has been widely used in rapid detection. Colorimetry is a quantitative analysis method, which generally includes two steps: one is to select an appropriate color developer to react with the component to be tested to form a colored compound; the other is to compare or measure the color depth of the colored compound, and then determine the color depth to be tested. component content. In the rapid detection and previous researches of Shuaixuan, a new colorimetric analysis method, that is, digital image colorimetry, is more and more widely used, and its principle includes two parts: image acquisition and image processing. Commonly used image acquisition tools include scanners, CCD or CMOS imagers, digital cameras, smart phones, etc. For image processing, different color models are selected and used according to the characteristics of color rendering reactions. This process is performed by professional image processing software or by writing mobile phones. APP to complete. Compared with visual colorimetry and photoelectric colorimetry, this colorimetric method is easy to operate, less time-consuming, low-cost, and the detection accuracy is between the visual colorimetry and photoelectric colorimetry. Therefore, its application is limited. extensive attention.

For digital image colorimetry, in recent years, researchers have developed some rapid detection methods. For example, Meng et al. (X. Meng, C. W. Schultz, C. Cui, X. Li, H. Yu, On-site chip-based colorimetric quantitation of organophosphorus pesticides using an officescanner, Sensors and Actuators B: Chemical, 2015, 215: 577 -583) A digital picture of the pesticide residue detection solution in the microfluidic channel was obtained using a common flatbed scanner, and then the Y value of the picture was analyzed to complete the quantitative detection of pesticide residues. When Li et al. (Li X, Tian J F, Shen W. Anal Bioanal Chem, 2010, 396(1): 495-501.) detected the nitrite ion concentration in water samples, they converted the pictures from RGB mode to Grayscale mode, and then analyze the relationship between grayscale intensity and nitrite ion concentration. Richard et al. (Murdock R C, Shen L, Optimization of a paper-based ELISA for a human performance biomarker. Analytical chemistry, 2013, 85(23): 11634-11642.) used a tablet computer to obtain the analytes of the substances to be tested in the filter paper microchannels. Digital picture, the detection of IgG (immunoglobulin) in human saliva is realized by analyzing the change of RGB value.

However, the above-mentioned detection methods have a limited scope of application, and for color reactions with obvious changes in hue, analyzing RGB values, gray values, or CMY values is no longer applicable. And Abe et al. (K. Abe, K. Suzuki, D.Citterio, Inkjet-printed microfluidic multianalyte chemical sensing paper. Analyticalchemistry, 2008, 80(18): 6928-6934) prepared the micro-particles on filter paper by using inkjet printing technology. In the fluid channel, the color development on the filter paper is captured by the scanner, and then the color is analyzed by the Lab chromaticity system, so as to realize the detection of various components in human urine. Shen et al. (Shen L, Hagen JA, Papautsky I, Point-of-care colorimetric detection with a smartphone[J]. Lab on a Chip, 2012, 12(21): 4240-4243.) established different pH values and their correlation with The three-dimensional relationship between the chromaticity coordinates xy of the color product, and this three-dimensional relationship can be relatively complicated when determining the pH value of a sample. Yetisen et al. (Yetisen AK, Martinez-Hurtado JL, Garcia-Melendrez A, A smartphone algorithm with inter-phonerepeatability for the analysis of colorimetric tests[J]. Sensors and Actuators B: Chemical, 2014, 196: 156-160.) in On the CIE 1931 chromaticity diagram, the line connecting the chromaticity coordinate points of the color of each standard after color development is used as the standard line, and the pH value and protein concentration of the sample are calculated by the relevant algorithm. Li Haiyan et al. (Li Haiyan, Zhang Xiaoliang, Li Xiaochun: Colorimetric Quantitative Detection Based on Color Dominant Wavelength and Complementary Color Wavelength _; Journal of Analysis and Testing, 2016, 11) used the dominant wavelength and complementary color wavelength of color combined with MATLAB to determine the pH and NO2 of solution ^-1 concentration for quantitative detection.

The above operation method has many operation steps and takes a long time to detect, and image acquisition and image processing are carried out separately, so it is not suitable for rapid on-site detection, and it is also difficult to carry out water quality testing in some remote or backward areas. With the widespread popularity of smart phones, more and more researchers use smart phones for detection and integrate image acquisition and image processing. For example, Lopez-Ruiz et al. (N. Lopez-Ruiz, V. F. Curto, M. MErenas, Smartphone-based simultaneous pH and nitrite colorimetric determination for paper microfluidic devices. Analytical chemistry, 2014, 86(19): 9554-9562) used a mobile phone to The color development in the microchannel on the filter paper was used to collect pictures, and then the pictures were analyzed by the mobile phone software to realize the quantitative detection of pH value and nitrous acid. Shen et al. (L. Shen , J.A. Hagen , I.Papautsky , Point-of-care colorimetric detection with a smartphone. Lab on aChip, 2012, 12(21): 4240-4243) used smartphone for image acquisition , the three-dimensional relationship between different pH values and the chromaticity coordinates x-y of their color products was established. Stéfani et al. (Andrade S IE, Lima M B, Barreto I S, A digital image-based flow-batch analyzer for determining Al(III) and Cr(VI) in water. Microchemical Journal, 2013, 109:106-111.) Using Networks The camera took pictures in a closed box equipped with fluorescent lamps, and realized the detection of aluminum ions and chromium ions in tap water by analyzing RGB values. It has the advantages of low cost and relatively short time-consuming, but it is relatively complicated to process. Based on this, the present invention proposes a digital picture colorimetry method based on a smartphone using the dominant wavelength or complementary wavelength of color, using a smartphone and writing an APP, so that the detection results are directly displayed on the mobile phone interface, which greatly shortens the detection time.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a molecular smart phone rapid detection method based on color dominant wavelength and complementary color wavelength, which realizes fast and accurate detection of biochemical samples anytime and anywhere based on smart phones, and has the advantages of simple operation, low cost, and a wide range of applications. wide features.

The detection reaction vessel mentioned in the present invention is a glass cuvette, PDMS microchannel or other clean and transparent vessel. The technical solutions adopted to achieve the above objects are as follows.

A kind of molecular smart phone speed measurement method based on color dominant wavelength and complementary color wavelength, the speed measurement method is carried out according to the following steps:

For sample preparation capable of producing chromogenic products;

A device for collecting pictures of colored products;

Smartphone detection program for solution color dominant wavelength and complementary color wavelength, displaying the color dominant wavelength or complementary color wavelength corresponding to different solutions;

Further, the additional technical solutions are as follows:

The preparation for the sample capable of producing a chromogenic product consists of a sample capable of producing a chromogenic product and having a distinct change in the hue of the product.

The picture of the color-developing product is obtained by taking pictures of the reaction vessel with the camera of the smartphone under the LED surface light source.

The rapid detection method is to use a smartphone App to take a picture of the reaction vessel under the condition that the sample can undergo a complete color reaction in the detection sample reaction vessel, and the mobile phone App intercepts the reaction and obtains the picture, and analyzes the picture to realize rapid detection. Quantitative detection.

To realize a colorimetric analysis-based quick measurement method for the color dominant wavelength and complementary color wavelength of a smartphone provided by the present invention, the sample to be tested and the corresponding color developer are mixed in a reaction vessel, and then placed in a reaction vessel. Under the LED surface light source, use the smartphone camera to take pictures, and analyze and fit the calibration equation through the written APP to obtain a test result of the sample solution to be tested, which is displayed on the result interface. The invention utilizes the dominant wavelength and the complementary wavelength of the color, and utilizes the detection program of the smart phone to realize the detection of the relevant parameters of the solution. The speed measurement method has the characteristics of low cost, strong operability, and short detection time. Therefore, it has good application prospects in the fields of environmental testing and water quality testing, especially in remote areas.

Description of drawings

Fig. 1 is the transparent base layer of the detection microchannel of the present invention.

Fig. 2 is the transparent channel layer of the detection microchannel of the present invention.

Fig. 3 is the transparent cover layer of the detection microchannel of the present invention.

Figure 4 is the present invention adding a color product.

FIG. 5 is the running interface of the smart phone detection program of the present invention.

In the figure: 1: transparent base layer; 2: transparent channel layer; 3: transparent cover layer; 3-1: sample injection hole for color product; 3-2: vent hole for color product; 4: pipette gun; 5: Smartphone detection program running interface; 5-1: main interface; 5-2: preview interface; 5-3: result interface.

Detailed ways

The following exemplary embodiments are made to further illustrate the specific embodiments of the present invention.

Example 1

Implement a method for rapid detection of molecular smart phones based on the dominant wavelength and complementary wavelength of color, including the following steps:

(1) Preparation of solutions with different pH values: use anhydrous sodium dihydrogen phosphate to prepare 0.2mol/L sodium dihydrogen phosphate solution, and citric acid to prepare 0.1mol/L solution, and then mix the two in different proportions to obtain pH values ranging from 4.0 to 8.5 (pH interval 0.5) solutions. Use sodium bicarbonate and sodium carbonate to prepare 0.1mol/L sodium bicarbonate solution and 0.1mol/L sodium carbonate solution, respectively, and mix the two in different proportions to obtain solutions with pH values of 9.0, 9.5, and 10.0. The pH of all solutions was determined with a STARTER 3100 pH meter.

(2) Preparation of pH developer: respectively take 0.01 g of thymol blue, 0.32 g of methyl red, 1.20 g of bromothymol blue, and 1.20 g of phenolphthalein, mix the two and grind them evenly, take 200 mL of 95% concentration The anhydrous ethanol was fully dissolved, and 150 mL of ultrapure water was added to dilute. Finally, use a 0.1 mol/L sodium hydroxide solution prepared with sodium hydroxide to neutralize the aforementioned solution until it just turns green, and add ultrapure water to make up the volume to 400 mL.

(3) Mixing of solutions with different pH values and color-developing reagents: Put 3 mL of buffer solutions with different pH values into colorimetric tubes, add 0.1 mL of color-developing solution into it, and shake well to fully develop color. reaction. Subsequently, 1 mL of the color product was injected into the designed microchannel.

(4) Uniform illumination of the sample: Place the above PDMS microchannel under an LED surface light source (18*18cm, 20W).

(5) The reading process of the smartphone detection program: First, fix the smartphone in front of the cuvette under the LED surface light source. Click the icon on the phone screen to enter the main interface. The main interface includes four buttons, namely Start, History, Instructions, and Quit. Click the Start button to enter the camera preview interface of the mobile phone. At this time, a large red rectangle will be displayed on the preview interface. There are six red narrow rectangles distributed in this rectangle. Align each rectangle at the preview interface. After the bar frame, click the Capture button, the program will automatically capture the picture in the red rectangle frame and save it to the mobile phone, then click the Analyze button, the program will automatically calculate the dominant wavelength of the color in each bar frame, and according to the standard solution The pH value of the solution and the corresponding color dominant wavelength are fitted to a calibration equation, and the pH value of the sample solution to be tested is calculated by combining this calibration equation and the color dominant wavelength corresponding to the solution to be tested, and finally the test results are directly displayed on the interface.

Example 2

The method in embodiment 1 is used to detect the concentration of nitrite ions in water, comprising the following steps:

(1) Preparation of sodium nitrite solutions of different concentrations: Take 0.025 g of sodium nitrite powder and dissolve it into 25 mL of ultrapure water to obtain 1000 mg/L sodium nitrite solution. Using this as the mother liquor, sodium nitrite solutions with concentrations of 0, 1, 2, 5, 10, 12, 15, 20, 25, 30, and 40 mg/L were prepared respectively.

(2) Preparation of nitrite display agent: take 0.1722 g of sulfonamide, 0.0518 g of naphthalene ethylenediamine hydrochloride and 0.317 g of citric acid, dissolve in 20 mL of methanol, and store at low temperature and dark before use.

(3) Mixing of different concentrations of sodium nitrite and chromogenic reagent: put 3 mL of different concentrations of sodium nitrite solution in a colorimetric tube, add 0.7 mL of chromogenic solution into it, and shake well to make it fully occur. color reaction. Subsequently, 1 mL of the color product was injected into the designed microchannel.

(4) Uniform illumination of the sample: Place the above PDMS microchannel under an LED surface light source (18*18cm, 20W).

(5) The reading process of the smartphone detection program: First, fix the smartphone in front of the cuvette under the LED surface light source. Click the icon on the phone screen to enter the main interface. The main interface includes four buttons, namely Start, History, Instructions, and Quit. Click the Start button to enter the camera preview interface of the mobile phone. At this time, a large red rectangular box will be displayed on the preview interface. There are six red narrow strip boxes distributed in this rectangular box. Align each rectangular box on the preview interface. After the bar box is displayed, click the Capture button, the program will automatically capture the picture in the red rectangle box and save it to the mobile phone, and then click the Analyze button, the program will automatically calculate the complementary color wavelength of the color in each bar box, and according to the standard The NO ₂ ^-1 concentration of the liquid and the corresponding color complementary color wavelength are fitted to a calibration equation, and the NO ₂ ^-1 concentration of the sample solution to be tested is calculated by combining this calibration equation and the color complementary color wavelength corresponding to the liquid to be tested, and finally the test results are directly displayed on the interface.

Claims (1)

1. A molecular smart phone speed measurement method based on color dominant wavelength and complementary color wavelength, the speed measurement method is carried out according to the following steps: For sample preparation capable of producing chromogenic products; A device for collecting pictures of color-developing products, used for taking pictures and collecting pictures with a smartphone; Smartphone detection program for solution color dominant wavelength and complementary color wavelength, displaying the color dominant wavelength or complementary color wavelength corresponding to different solutions; The specific method of the quick test is carried out according to the following specific steps: (1) The sample preparation for generating a color product is composed of a sample whose color product changes significantly in hue with the change of the relevant parameters of the sample; (2) For placing the sample to be detected under the device for collecting the color product, to realize the color reaction of quantitative detection of the sample, the color of the sample reaction vessel can be read out by the mobile phone reading device. Corresponding data As a result, the picture information after the reaction is intercepted, the obtained picture is analyzed, and the detection result is displayed by comparing with the control result; (3) The smart phone detection program for the dominant wavelength and complementary color wavelength of the solution color, the smart phone testing program can automatically calculate the dominant wavelength or complementary color wavelength of the color, and according to the pH value of the standard solution and the corresponding color dominant wavelength Combine the calibration equation, calculate the pH value of the sample solution to be tested by combining the calibration equation and the color dominant wavelength corresponding to the test solution, or fit the calibration equation according to the NO ₂ ^-1 concentration of the standard solution and the corresponding color complementary color wavelength, Calculate the NO ₂ ^-1 concentration of the sample solution to be tested by combining the calibration equation and the color complementary wavelength corresponding to the liquid to be tested, and display the test result, which is written in Java and runs on the Android mobile phone platform; The reaction vessel is a cuvette, a PDMS microchannel or other transparent devices; The device for collecting pictures of color-developing products is used for taking pictures and collecting pictures with a smartphone, and is completed by placing the reaction vessel containing the color-developing products under an LED surface light source; The rapid detection method is that under the condition that the sample undergoes a complete color reaction in the sample reaction vessel, the reaction vessel after the color reaction is photographed by using a mobile phone App, and the picture is obtained after the reaction is intercepted according to the mobile phone App, and the picture is analyzed. Realize rapid quantitative detection.

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