Organic small molecules, liquor identification method and colorimetric array sensor based on 4-aminoantipyrine, aromatic phenol and copper ion

Abstract

The present invention discloses an organic small molecule and liquor identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, and a colorimetric array sensor, which belongs to the technical field of organic identification and bionic sensor. Aiming at the problems existing in the identification of organic small molecules and liquor and other complex systems in the prior art, the present invention provides an organic small molecule and liquor identification method, which uses carboxylic acid compounds and aldehyde-ketone compounds to cause different degrees of inhibition on the reaction of 4-aminoantipyrine with phenol and its derivatives, thereby realizing the identification of a variety of carboxylic acids, aldehyde-ketone compounds; and a series of colorimetric array sensors are designed using this method, which can be used for the quantitative and qualitative analysis of acids, aldehyde-ketone compounds and the detection of complex matrices such as liquor rich in such compounds.

Description

Technical Field

[0001] The invention belongs to the technical field of organic identification and bionic sensors, and specifically relates to an organic small molecule based on 4-aminoantipyrine, aromatic phenol and copper ions, a liquor identification method and a colorimetric array sensor. Background Art

[0002] Array sensors are designed to mimic the olfactory and taste systems of mammals, and use multiple sensor units to build arrays. Each individual sensor unit does not have to be highly selective for the analyte, but has different response capabilities to different components. The difference between the overall responses of the sensor array to various analytes is used to distinguish the analytes. Array sensors accurately identify the overall characteristics of the target through specific responses or cross-responses to multiple analytes or complex mixtures. Without relying on studying each component of a single sample, a single component can be associated with macro information such as the overall quality style of liquor. Array sensors mainly include fluorescence array sensors and colorimetric array sensors. The former often needs to be combined with a fluorescence spectrometer to realize the analysis and detection of the target, while the latter can realize the detection of the target by color extraction and analysis under visible light. At present, array sensors have been successfully applied to the analysis and detection of many complex systems. They are mainly used for the distinction and identification of complex systems such as coffee, beer, distilled liquor, soft and hard materials, and Chinese liquor. They provide unique color fingerprints to identify different target analytes by obtaining the color difference value before and after the array reaction.

[0003] However, it is difficult for array sensors to distinguish and identify multiple analytes at the same time, and most of the materials that make up the sensor units are unstable, such as metal quantum dots, precious metal nanomaterials, etc. They are often difficult to synthesize again, which greatly limits the development of practical detection applications. In addition, another part of the sensing materials often involves complex synthesis methods, such as organic luminescent molecules, etc., which have the disadvantages of cumbersome production processes and high costs.

[0004] 4-aminoantipyrine, as a colorimetric agent, can be used to detect polyphenols in aqueous solutions. Studies have shown that 4-aminoantipyrine and phenolic substances will generate brightly colored quinoneimine dyes under the conditions of oxidants such as hydrogen peroxide, persulfate, and copper ions. Based on this color reaction, it has been used in the detection of toxic phenolic pollutants and analytes such as ions. The reaction is simple, stable, and does not require complex synthetic methods to obtain color-developing raw materials. However, there has been no report on the redox colorimetric reaction based on 4-aminoantipyrine and phenol under the oxidation conditions of copper ions to achieve the detection of small organic molecules and the identification of complex matrices rich in these molecules. Summary of the invention

[0005] In order to solve the technical gaps and defects existing in the above research background, the present invention provides an identification method for carboxylic acid, aldehyde and ketone organic small molecules and substances rich in these small molecules such as liquor constructed by 4-aminoantipyrine and phenol and its derivatives under the oxidation conditions of copper ions, and designs a colorimetric array sensor based on this principle. The sensor has the advantages of no need for synthesis, easy availability of raw materials, low cost and easy implementation, and can be widely used in the identification of various organic small molecules and the visual online detection of samples rich in such compounds.

[0006] The present invention first provides an organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, which comprises the following steps:

[0007] A. Mixing a solvent, 4-aminoantipyrine, aromatic phenol A and copper ions to obtain an identification system A; mixing a solvent, 4-aminoantipyrine, aromatic phenol B and copper ions to obtain an identification system B;

[0008] B. Adding the organic small molecule solution to the identification system A to obtain sample group A, adding the organic small molecule solution to the identification system B to obtain sample group B, and using an equal volume of the solvent used for the organic small molecule solution as a control;

[0009] C. Record the fingerprints of sample group A, sample group B and control group, extract the R, G and B values ​​of sample group A, sample group B and control group, subtract the R, G and B values ​​of the corresponding control group from the R, G and B values ​​of the sample group to obtain the R, G and B difference of the organic small molecule;

[0010] Qualitative analysis: Perform linear discriminant analysis on the R, G and B differences, perform qualitative analysis based on the results of linear discriminant analysis, and / or obtain a color difference diagram based on the R, G and B differences, and identify with the naked eye;

[0011] Quantitative analysis: The Euclidean distance is calculated by the difference of R, G and B of the organic small molecules in sample group A and sample group B, and the total Euclidean distance is obtained by adding the calculated Euclidean distances of sample group A and sample group B. The standard curve is plotted with the logarithm of the organic small molecule concentration as the abscissa and the total Euclidean distance as the ordinate to obtain a linear equation, and quantitative analysis is performed using the standard curve and the linear equation;

[0012] In step A, the aromatic phenol A is catechol, 3-aminophenol, 4-aminophenol, m-methylphenol, 4-methylphenol, 2-aminophenol, 3-aminophenol, 4-aminophenol or 2-methylaminophenol, the aromatic phenol B is catechol, 3-aminophenol, 4-aminophenol, m-methylphenol, 4-methylphenol, 2-aminophenol, 3-aminophenol, 4-aminophenol or 2-methylaminophenol, and the aromatic phenol A and aromatic phenol B are different;

[0013] In step A, the solvent is at least one of water or ethanol;

[0014] When it is a qualitative analysis, the following conditions are met:

[0015] The organic small molecules are 7 carboxylic acids and 4 aldehydes and ketones, specifically at least one of acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid, octanoic acid, acetaldehyde, furfural, 2,3-butanedione or 3-hydroxy-2-butanone; in step B, the solvent used for the organic small molecule solution is at least one of water, ethanol or liquor;

[0016] When performing quantitative analysis, the following conditions must be met:

[0017] The organic small molecules are 7 carboxylic acids and 4 aldehydes and ketones, specifically acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, hexanoic acid, octanoic acid, acetaldehyde, furfural, 2,3-butanedione or 3-hydroxy-2-butanone; in step B, the solvent used for the organic small molecule solution is at least one of water or ethanol.

[0018] Among them, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, in step B, after adding the organic small molecule solution to the identification system A, the reaction is carried out for 10 to 20 minutes.

[0019] Among them, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, in step B, after adding the organic small molecule solution to the identification system B, the reaction is carried out for 10 to 20 minutes.

[0020] Wherein, in the above-mentioned method for identifying small organic molecules based on 4-aminoantipyrine, aromatic phenol and copper ions, in step B, the concentration of the small organic molecules in the sample group A and the sample group B is 0.00025-25 mmol / L.

[0021] Wherein, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, in step B, the concentration of 4-aminoantipyrine in the sample group A is 0.5-5 mmol / L.

[0022] Wherein, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, in step B, the concentration of 4-aminoantipyrine in the sample group B is 0.5-5 mmol / L.

[0023] Wherein, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, in step B, the concentration of aromatic phenol A in the sample group A is 0.5-5 mmol / L.

[0024] Wherein, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, in step B, the concentration of aromatic phenol B in the sample group B is 0.5-5 mmol / L.

[0025] Among them, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ions, in step A, the copper ions are derived from at least one of copper nitrate, copper sulfate or copper chloride.

[0026] Among them, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, in step B, the copper ion concentration in the sample group A is 0.5-5 mmol / L.

[0027] Wherein, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, in step B, the copper ion concentration in the sample group B is 0.5-5 mmol / L.

[0028] Among them, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, in step B, the molar concentration ratio of 4-aminoantipyrine: aromatic phenol A: copper ion in the sample group A is 1~2:1~2:1~2.

[0029] Among them, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrline, aromatic phenol and copper ion, in step B, the molar concentration ratio of 4-aminoantipyrline: aromatic phenol B: copper ion in the sample group B is 1~2:1~2:1~2.

[0030] Among them, in the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, when performing qualitative analysis and obtaining a color difference diagram, the difference between R, G and B is magnified by 2 to 6 times.

[0031] The present invention detects multiple concentrations of 11 acids, aldehydes and ketones in the concentration range of 0.00025 to 25 mmol / L. After analysis, the total Euclidean distance of the 11 acids, aldehydes and ketones and the logarithm of the concentration show a good linear relationship. In the above-mentioned organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, the obtained linear equation is as follows during quantitative analysis:

[0032]

[0033]

[0034] Where Y is the total Euclidean distance, and logC is the logarithm of the concentration of organic small molecules.

[0035] The present invention also realizes the identification of complex systems such as liquor, and provides a liquor identification method based on 4-aminoantipyrine, aromatic phenol and copper ion. The qualitative identification of liquor is the same as the qualitative identification principle of organic small molecules. On the basis of the above-mentioned organic small molecule qualitative analysis steps, the organic small molecule solution is replaced with liquor (liquor does not need additional operations such as dilution, and the original liquor sample can be directly detected), and an equal volume of Vol40-70% ethanol aqueous solution is used as a control.

[0036] Based on the above-mentioned quantitative and qualitative identification method for organic small molecules and liquor, the present invention also provides a colorimetric array sensor based on 4-aminoantipyrine, aromatic phenol and copper ions. The detection principle of the sensor is the same as the above-mentioned identification method, so it includes N first sensor units U1 and N second sensor units U2, the substance in U1 is the identification system A in the above-mentioned identification method, and the substance in U2 is the identification system B in the above-mentioned identification method; N is an integer greater than 0.

[0037] In the above colorimetric array sensor based on 4-aminoantipyrine, aromatic phenol and copper ions, after adding the analyte to each sensing unit, the total amount of the final system added is controlled to be 50 to 200 μL.

[0038] Among them, in the above-mentioned colorimetric array sensor based on 4-aminoantipyrline, aromatic phenol and copper ions, after the analyte is added, the concentration of 4-aminoantipyrline, the concentration of aromatic phenol A, the concentration of copper ions and the total volume in each sensing unit U1 are controlled to be the same; after the analyte is added, the concentration of 4-aminoantipyrline, the concentration of aromatic phenol A, the concentration of copper ions and the total volume in each sensing unit U2 are controlled to be the same.

[0039] The beneficial effects of the present invention are:

[0040] The present invention constructs an identification method for complex systems such as carboxylic acid compounds, aldehydes and ketones, and liquor based on 4-aminoantipyrine and phenol and its derivatives under the oxidation conditions of copper ions. The present invention uses carboxylic acid compounds and aldehydes and ketones compounds to cause different degrees of inhibition on the reaction of 4-aminoantipyrine and phenol and its derivatives, thereby achieving quantitative and qualitative identification of a variety of carboxylic acids, aldehydes and ketones; in addition, there are certain differences in the types and contents of carboxylic acid compounds and aldehydes and ketones contained in liquors of different brands, grades and origins, resulting in the generation of differentiated results. Based on the same principle, the present invention can ultimately achieve the identification of liquors and mixed liquors from different origins, flavors, brands, grades and years.

[0041] Compared with traditional sensors, the sensor based on the above principle has many advantages such as easy availability of raw materials and low cost. It does not require complex synthesis methods and can be applied to the qualitative identification of various carboxylic acids, aldehydes and ketones, as well as the identification of complex samples such as liquor rich in such compounds. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 The present invention is a schematic diagram of a method for detecting carboxylic acids and aldehydes and ketones organic small molecule compounds and identifying actual samples rich in such compounds using a colorimetric array sensor constructed based on 4-aminoantipyrine and phenol and its derivatives under copper ion oxidation conditions.

[0043] Figure 2 This is the colorimetric diagram of the dual-channel colorimetric array sensor in Example 1 for 7 carboxylic acids and 4 aldehyde and ketone compounds, which are carboxylic acids and aldehyde and ketone compounds with concentrations of 0.00025 to 25 mmol / L from top to bottom.

[0044] Figure 3 This is a color difference diagram of the dual-channel colorimetric array sensor in Example 1 after 4 times magnification of 7 carboxylic acids and 4 aldehydes and ketones. From top to bottom, they are carboxylic acids and aldehydes and ketones with concentrations ranging from 0.00025 to 25 mmol / L.

[0045] Figure 4 This is the LDA discrimination result diagram of 0.25mmol / L 7 carboxylic acids and 4 aldehyde and ketone compounds in Example 1; among them, (A) is divided into 7 categories according to the type of carboxylic acid, (B) is divided into 4 categories according to the type of aldehyde and ketone, (C) is divided into 11 categories according to the type of carboxylic acid and aldehyde and ketone, and (D) is divided into 3 categories according to carboxylic acids, aldehydes, and ketones.

[0046] Figure 5 It is the linear relationship diagram of acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid and octanoic acid in Example 1.

[0047] Figure 6 This is a linear relationship diagram of acetaldehyde, furfural, 2,3-butanedione and 3-hydroxy-2-butanone in Example 1.

[0048] Figure 7 This is the colorimetric diagram of 24 kinds of Chinese liquor in Example 2.

[0049] Figure 8 This is a color difference diagram of the 24 kinds of liquor in Example 2 after being magnified 4 times.

[0050] Fig. 9 Graph showing the LDA discrimination results of 24 kinds of Chinese liquor in Example 2; wherein, (A) is divided into 3 categories by faction, (B) is divided into 18 categories by brand for the three major factions, (C) is divided into 4 categories by flavor, and (D) is divided into 24 categories by brand.

[0051] Fig.10 These are the colorimetric diagrams and color difference diagrams of 4 wines of different years in Example 3; the left one is the colorimetric diagram, and the right one is the color difference diagram.

[0052] Fig.11 This is the LDA discrimination result diagram of 4 wines of different years in Example 3.

[0053] Fig.12 This is a chromatic aberration diagram of LZ-5 and LZ-4, MT and MTWZJ mixed in different proportions in Example 4, magnified 4 times.

[0054] Fig.13 The figure is the LDA discrimination result diagram of the mixed wine samples in Example 4; wherein (A) is a mixed wine sample of LZ-5 and LZ-4, and (B) is a mixed wine sample of MT and MTWZJ. DETAILED DESCRIPTION

[0055] The present invention constructs a colorimetric array sensor based on 4-aminoantipyrine and phenol and its derivatives under the oxidation condition of copper ions for detecting carboxylic acid and aldehyde-ketone compounds. Its detection mechanism is that 4-aminoantipyrine and phenol and its derivatives will generate colorful quinone imine dyes under copper ion oxidation, wherein the product dye color of 4-aminoantipyrine and aromatic phenol A (such as catechol) under copper ion conditions (U1) is green, and the product dye color of 4-aminoantipyrine and aromatic phenol B (such as 3-aminophenol) under copper ion conditions (U2) is red. When carboxylic acid compounds are introduced into the system, the hydrogen ions ionized by the carboxylic acid will cause the protonation of the amino group on 4-aminoantipyrine, thereby greatly reducing the coupling of 4-aminoantipyrine and phenol, resulting in the reduction of its final color dye product. In addition, aldehyde-ketone compounds will react with the amino group on 4-aminoantipyrine to reduce its content by nucleophilic addition reaction, which will eventually lead to the reduction of color dye products.

[0056] Since carboxylic acid compounds and aldehyde and ketone compounds will cause different degrees of inhibition on the reaction, it is possible to identify carboxylic acid and aldehyde and ketone compounds of different types and concentrations; and there are certain differences in the types and contents of carboxylic acid compounds and aldehyde and ketone compounds contained in liquors of different brands, grades and origins, resulting in differentiated results, and ultimately it is possible to identify liquors and / or mixed liquors from different origins, flavors, brands, grades and years.

[0057] Specifically, the present invention first provides an organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, which comprises the following steps:

[0058] A. Mixing a solvent, 4-aminoantipyrine, aromatic phenol A and copper ions to obtain an identification system A; mixing a solvent, 4-aminoantipyrine, aromatic phenol B and copper ions to obtain an identification system B;

[0059] B. Adding the organic small molecule solution to the identification system A to obtain sample group A, adding the organic small molecule solution to the identification system B to obtain sample group B, and using an equal volume of the solvent used for the organic small molecule solution as a control;

[0060] C. Record the fingerprints of sample group A, sample group B and control group, extract the R, G and B values ​​of sample group A, sample group B and control group, subtract the R, G and B values ​​of the corresponding control group from the R, G and B values ​​of the sample group to obtain the R, G and B difference of the organic small molecule;

[0061] Qualitative analysis: Perform linear discriminant analysis on the R, G and B differences, perform qualitative analysis based on the results of linear discriminant analysis, and / or obtain a color difference diagram based on the R, G and B differences, and identify with the naked eye;

[0062] Quantitative analysis: The Euclidean distance is calculated by the difference of R, G and B of the organic small molecules in sample group A and sample group B, and the total Euclidean distance is obtained by adding the calculated Euclidean distances of sample group A and sample group B. The standard curve is plotted with the logarithm of the organic small molecule concentration as the abscissa and the total Euclidean distance as the ordinate to obtain a linear equation, and quantitative analysis is performed using the standard curve and the linear equation;

[0063] In step A, the aromatic phenol A is catechol, 3-aminophenol, 4-aminophenol, m-methylphenol, 4-methylphenol, 2-aminophenol, 3-aminophenol, 4-aminophenol or 2-methylaminophenol, the aromatic phenol B is catechol, 3-aminophenol, 4-aminophenol, m-methylphenol, 4-methylphenol, 2-aminophenol, 3-aminophenol, 4-aminophenol or 2-methylaminophenol, and the aromatic phenol A and aromatic phenol B are different;

[0064] In step A, the solvent is at least one of water or ethanol;

[0065] When it is a qualitative analysis, the following conditions are met:

[0066] The organic small molecules are 7 carboxylic acids and 4 aldehydes and ketones, specifically at least one of acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid, octanoic acid, acetaldehyde, furfural, 2,3-butanedione or 3-hydroxy-2-butanone; in step B, the solvent used for the organic small molecule solution is at least one of water, ethanol or liquor;

[0067] When performing quantitative analysis, the following conditions must be met:

[0068] The organic small molecules are 7 carboxylic acids and 4 aldehydes and ketones, specifically acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, hexanoic acid, octanoic acid, acetaldehyde, furfural, 2,3-butanedione or 3-hydroxy-2-butanone; in step B, the solvent used for the organic small molecule solution is at least one of water or ethanol.

[0069] In the method of the present invention, the copper ions may be derived from common soluble salts in the art, such as at least one of copper nitrate, copper sulfate or copper chloride.

[0070] In step B of the method of the present invention, after adding the organic small molecule solution to the identification system A, the reaction is carried out for 10 to 20 minutes; after adding the organic small molecule solution to the identification system B, the reaction is carried out for 10 to 20 minutes. When the reaction time is reached, the image can be recorded by a camera for later processing of the image by Photoshop and extraction of R, G and B values. The above-mentioned photographing method is generally carried out in a dark room to eliminate the influence of ambient light on the acquisition of fingerprint spectrum to the greatest extent.

[0071] In step B of the method of the present invention, the concentration of the organic small molecules in sample group A and sample group B is 0.00025-25 mmol / L.

[0072] In step B of the method of the present invention, the concentration of 4-aminoantipyrine in sample group A is 0.5-5 mmol / L, the concentration of aromatic phenol A in sample group A is 0.5-5 mmol / L, and the concentration of copper ions in sample group A is 0.5-5 mmol / L; the concentration of 4-aminoantipyrine in sample group B is 0.5-5 mmol / L; the concentration of aromatic phenol B in sample group B is 0.5-5 mmol / L; and the concentration of copper ions in sample group B is 0.5-5 mmol / L. In each identification system, the concentrations of the three materials can be appropriately adjusted according to the concentration of the organic small molecule to be detected.

[0073] In the embodiment of the present invention, in the laboratory stage, in order to ensure the accuracy of the amount, 4-aminoantipyrine, catechol, 3-aminophenol, and copper ion salt are first prepared into an initial solution, and then a certain amount is taken to prepare a final concentration identification system. However, in actual application, it is not necessary to follow the operation of the embodiment of the present invention, as long as the final concentration of each material meets the requirements.

[0074] In step B of the method of the present invention, the molar concentration ratio of 4-aminoantipyrline: aromatic phenol A: copper ions in sample group A is 1-2:1-2:1-2, and the molar concentration ratio of 4-aminoantipyrline: aromatic phenol B: copper ions in sample group B is 1-2:1-2:1-2.

[0075] The above method can be specifically operated as follows: first, aromatic phenol A (such as catechol) / aromatic phenol A (such as 3-aminophenol), copper ion salt, ethanol and 4-aminoantipyrine are added to the first row or first column of a 96-well plate as a control group, and aromatic phenol A (such as catechol) / aromatic phenol A (such as 3-aminophenol), copper ion salt and 4-aminoantipyrine of equal volume and concentration are added below or to the right of the same row or column, and the ethanol solution is replaced by an organic small molecule solution prepared with the same volume of ethanol or a sample containing such an organic small molecule, and the order of adding samples is the same as the order of solutions in the control. By obtaining the R, G and B values ​​between the reaction well where the organic molecule is located and the control in the same row or column, the corresponding R, G and B differences can be obtained. From the above scheme, it can be seen that the dual-channel sensor array can form 2*3 characteristic values, and each concentration and each organic small molecule has its corresponding 2*3 characteristic values. In this way, compounds can be discriminated through linear discriminant analysis (LDA), thereby achieving the distinction between different organic small molecules and further identifying the types, origins and brands of complex samples enriched with such organic small molecules.

[0076] In the present invention, the R, G and B differences can be directly used to obtain a color difference diagram, through which the small molecule solution can be distinguished to a certain extent; in addition, in order to make the naked eye observation relatively more obvious, the present invention can amplify the R, G and B differences by 2 to 6 times, and then obtain a color difference diagram, which can also be distinguished by the naked eye.

[0077] In the embodiment of the present invention, 11 concentrations of 11 acids, aldehydes and ketones in the concentration range of 0.00025mmol / L to 10mmol / L were detected. After analysis, the total Euclidean distance of the 11 organic small molecules and the logarithm of the concentration showed a good linear relationship, and the obtained linear equation was as follows:

[0078]

[0079] Where Y is the total Euclidean distance, and logC is the logarithm of the concentration of organic small molecules.

[0080] The method of the present invention can use linear discriminant analysis for qualitative identification. Linear discriminant analysis is a supervised classification method. This method defines the sample category in advance and distinguishes samples of different categories. It generally analyzes the data through software such as SYSTAT13.2. In linear discriminant analysis, for different samples in the same series, the conditions of the reaction system of the two different samples need to be kept as consistent as possible. For a single sample in the same series, the conditions in the two channels are not required to be exactly the same. Since different series are not distinguished from each other as references, the conditions can be different.

[0081] When the method of the present invention is used for quantitative identification, the method of drawing the standard curve and calculating the linear equation is a conventional method in the art. For example, when the concentration of the organic small molecule in sample groups A and B is in the range of 0.00025 to 25 mmol / L, several points are taken, and the sample preparation and detection are performed according to the aforementioned method. The linear relationship of these points is analyzed and then used for quantitative analysis of the concentration of unknown samples. When quantitative identification is used, the Euclidean distance is calculated by the difference between R, G and B (i.e., ΔR, ΔG, ΔB). The Euclidean distance calculation formula is: The sum of the Euclidean distances between sample group A and sample group B is the total Euclidean distance.

[0082] The present invention also realizes the identification of complex systems such as liquor, and provides a liquor identification method based on 4-aminoantipyrine, aromatic phenol and copper ion. The qualitative identification of liquor is the same as the qualitative identification principle of organic small molecules. On the basis of the above-mentioned organic small molecule qualitative analysis steps, the organic small molecule solution sample is replaced with a liquor sample, and because the ethanol solution has little effect on U1 and U2, an equal volume of Vol40-70% ethanol aqueous solution (this range includes the alcohol content range of most liquors) can be used as a control.

[0083] On the basis of the above-mentioned quantitative and qualitative identification method for organic small molecules and liquor, the present invention also provides a colorimetric array sensor based on 4-aminoantipyrine, aromatic phenol and copper ion. The detection principle of the sensor is the same as the above-mentioned identification method, so it includes N first sensing units U1 and N second sensing units U2, the substance in U1 is the identification system A in the above-mentioned identification method, and the substance in U2 is the identification system B in the above-mentioned identification method; N is an integer greater than 0. The principle of the colorimetric array sensor is the principle of the above-mentioned identification method, so when using the colorimetric array sensor, the quantitative and qualitative identification of organic small molecules and liquor can be achieved by operating according to the above-mentioned identification method.

[0084] In the above colorimetric array sensor based on 4-aminoantipyrine, aromatic phenol and copper ions, after adding the analyte to each sensing unit, the total amount of the final system added is controlled to be 50 to 200 μL.

[0085] Among them, in the above-mentioned colorimetric array sensor based on 4-aminoantipyrine, aromatic phenol and copper ions, after the addition of the analyte, the concentration of 4-aminoantipyrine, the concentration of aromatic phenol A, the concentration of copper ions and the total volume in each sensing unit U1 are controlled to be the same; after the addition of the analyte, the concentration of 4-aminoantipyrine, the concentration of aromatic phenol B, the concentration of copper ions and the total volume in each sensing unit U2 are controlled to be the same; thereby ensuring the accuracy of the results between the same series or batches of samples in the sensor.

[0086] The present invention is further described in detail below by way of examples, but the protection scope of the present invention is not limited to the scope of the examples.

[0087] Example 1

[0088] The colorimetric array sensor constructed in this embodiment can be used for the detection of 7 carboxylic acid compounds and 4 aldehyde and ketone compounds at different concentrations. It should be specifically explained that the identification system A of the sensing unit 1 (U1) is: water (35 μL) + catechol (1.5 mmol / L) + copper nitrate (1.5 mmol / L) + 4-aminoantipyrine (3.0 mmol / L); the identification system B of the sensing unit 2 (U2) is: water (35 μL) + 3-aminophenol (1.5 mmol / L) + copper nitrate (1.5 mmol / L) + 4-aminoantipyrine (3.0 mmol / L).

[0089] In this embodiment, catechol, 3-aminophenol, copper nitrate, and 4-aminoantipyrine are first prepared into 10mmol / L initial solutions, and ultrapure water is used as the solvent. Therefore, in order to obtain the above-mentioned identification systems A and B, the specific sample addition method is as follows: for U1: the control group is water (35μL) + catechol (15μL) + copper nitrate (15μL) + 4-aminoantipyrine (30μL) + anhydrous ethanol (5μL), and the test group is water (35μL) + catechol (15μL) + copper nitrate (15μL) + 4-aminoantipyrine (30μL) + anhydrous ethanol prepared organic small molecule solution (5μL), the total amount of the control group and the test group is The volume was 100 μL for both groups; for U2: the control group was water (35 μL) + 3-aminophenol (15 μL) + copper nitrate (15 μL) + 4-aminoantipyrine (30 μL) + anhydrous ethanol (5 μL); the test group was water (35 μL) + 3-aminophenol (15 μL) + copper nitrate (15 μL) + 4-aminoantipyrine (30 μL) + anhydrous ethanol prepared organic small molecule solution (5 μL); the total volume of the control group and the test group was 100 μL for both groups.

[0090] The carboxylic acids and aldehydes and ketones identified in this example include acetic acid (A1), propionic acid (A2), butyric acid (A3), isobutyric acid (A4), valeric acid (A5), hexanoic acid (A6), octanoic acid (A7), acetaldehyde (AH1), furfural (AH2), 2,3-butanedione (KT1), and 3-hydroxy-2-butanone (KT2).

[0091] In this embodiment, all organic small molecule solutions are prepared with anhydrous ethanol, and their original concentration range is 0.005-500mmol / L, so as to ensure that when 5 μL of the above solution is added to the identification system, the final concentration of the organic small molecules in the system is 0.00025mmol / L-25mmol / L, and this concentration range covers the actual concentrations of 11 organic small molecules in liquor. Within this range, each organic small molecule is prepared with 11 concentrations, and its final concentrations in the system are: 0.00025mmol / L, 0.00125mmol / L, 0.0025mmol / L, 0.0125mmol / L, 0.025mmol / L, 0.125mmol / L, 0.25mmol / L, 1.25mmol / L, 2.5mmol / L, 12.5mmol / L, 25mmol / L.

[0092] In order to control the effect of the addition time on the reaction, all samples of the same type were added using an eppendorf multichannel pipette. After the last sample was added, it was mixed evenly and reacted for 15 min at room temperature. Then the 96-well plate was placed on a shadowless bottom lamp and photographed with a SLR camera in a dark room to record the fingerprint of each carboxylic acid and aldehyde ketone compound, such as Figure 2 As shown, each compound was tested in triplicate. Figure 2 It can be seen that the array sensor has different responses to different carboxylic acids and aldehydes and ketones by visual judgment alone. The R, G and B values ​​of the captured images were extracted through Photoshop, and the R, G and B values ​​of the detection group were subtracted from the R, G and B values ​​of the corresponding control group to obtain the R, G and B difference of each carboxylic acid and aldehyde and ketone compound at each concentration. The color difference diagram drawn by the difference (magnified 4 times) is shown in the figure below. Figure 3 As shown, from Figure 3 It can be seen that the array sensor has different responses to different carboxylic acids and aldehydes and ketones only by visual identification; and SYSTAT13.2 is used for linear discriminant analysis (LDA).

[0093] The LDA results of carboxylic acids and aldehydes and ketones at a concentration of 0.25 mmol / L are as follows: Figure 4 As shown, whether it is divided into 7 categories according to carboxylic acid types, 4 categories according to aldehydes and ketones, 11 categories according to 11 carboxylic acids and aldehydes and ketones, or 3 categories according to carboxylic acids, aldehydes, and ketones, the discrimination accuracy is 100%.

[0094] In this example, in order to evaluate the performance of the dual-channel colorimetric array sensor, the total Euclidean distance of U1 and U2 was used to quantitatively analyze 7 carboxylic acids and 4 aldehydes and ketones. The total Euclidean distance of these 11 organic small molecules showed a good linear relationship with the logarithm of the concentration. Their quantitative relationship diagram is shown in Figure 2. Figure 5 , Figure 6 The specific quantitative results are shown in Table 1.

[0095] Table 1 Quantitative data of 11 organic small molecules

[0096]

[0097] Example 2

[0098] The array sensor constructed in this embodiment can recognize different types of Chinese liquor samples on the basis of identifying carboxylic acids and aldehydes and ketones. Liquor contains abundant flavor substances, including aldehydes, ketones, carboxylic acids and other main flavor substances. Due to the different contents and proportions of flavor substances contained in each type of liquor, different flavors and types of liquor are formed. At present, Chinese liquor is divided into 12 major flavors, including 4 main flavors: strong aroma, sauce aroma, light aroma and rice aroma. The remaining 8 flavors of liquor are derivative flavors of the 4 main flavors: mixed aroma, phoenix aroma, sesame aroma, soy aroma, special aroma, medicinal aroma, Lao Baigan aroma and rich aroma.

[0099] In order to explore the practical application of the colorimetric array sensor, we selected 24 liquors from four major flavors in China, including 18 strong-flavor liquors (they come from the three major factions of strong-flavor liquors), 2 sauce-flavor liquors, 3 light-flavor liquors and 1 rice-flavor liquor. The specific information is shown in Table 2.

[0100] Table 2 Detailed information of 24 kinds of Chinese liquor

[0101]

[0102]

[0103] The method and steps for identifying liquor by the array are the same as those for identifying carboxylic acid and aldehyde ketone compounds in Example 1. It is only necessary to replace the organic small molecule compound solution with an equal volume of liquor (liquor does not need to be diluted, and the original liquor sample can be directly detected). The control under each channel is 5 μL, Vol 53% ethanol solution, and the other conditions are the same. After 15 minutes, the fingerprint spectrum of each liquor sample is recorded, such as Figure 7 By extracting the R, G and B values ​​of each reaction well, we can obtain the R, G and B difference between each wine sample and the control. After amplifying the difference by 4 times, we can get the following Figure 8 Color difference diagram shown.

[0104] In order to obtain more accurate analysis and discrimination results, we introduced the linear discriminant analysis (LDA) analysis method to discriminate 24 liquor samples. For the same Luzhou-flavor liquor, whether it is divided into 3 categories according to factions or 18 categories according to brands or grades, the results show that there is no overlap, and the discrimination accuracy is 100% ( Fig. 9 A, 9B). Secondly, all wine samples were divided into 4 categories according to flavor or 24 categories according to brand. The LDA results showed that all analytes could be strictly classified without confusion or misclassification, and the discrimination accuracy was 100% ( Fig. 9 C, 9D). The above results show that the sensor array has good recognition ability for Chinese liquor.

[0105] Example 3

[0106] The array sensor constructed in this embodiment can not only identify 24 kinds of Chinese liquor, but also liquors of the same brand and grade but of different years. We selected 4 different years of liquor from the same liquor of Luzhou Laojiao, which are 4 years, 7 years, 11 years and 14 years. In terms of technical operation, the method and steps of the array sensor for identifying liquors of different years are the same as those in Example 2. It is only necessary to replace the liquor sample with the same volume of vintage liquor (the liquor does not need to be diluted, and the original liquor sample can be directly detected). The colorimetric and color difference diagrams of the 4 vintage liquors are shown in the figure below. Fig.10 As shown. By introducing LDA to analyze the four vintages, the discrimination accuracy is 100%, as shown Fig.11 shown.

[0107] Example 4

[0108] The array sensor constructed in this embodiment can distinguish mixed liquor samples based on the identification of 24 kinds of Chinese liquor and 4 kinds of vintage liquor, which is of great practical significance for identifying liquor adulteration. We take liquor of the same brand and different grades as an example to evaluate the feasibility of the colorimetric array sensor. These include the mixture of two liquors, Guojiao 1573 (LZ-5) and Luzhou Laojiao-Tequ (LZ-4) in different proportions, and the mixture of two liquors, Maotai (MT) and Maotai Prince Liquor (MTWZJ) in different proportions, with the volume ratios of LZ-5:LZ-4=9:1, 8:2, 7:3 and 5:5; MT:MTWZJ=9:1, 8:2, 7:3 and 5:5.

[0109] The specific implementation of the mixed wine sample is the same as that of the identification of white wine and vintage wine. It is only necessary to replace the white wine sample in the array with the white wine mixed sample of the same volume. The fingerprint of the two types of mixed wine samples is as follows Fig.12By introducing LDA to analyze the mixed liquor samples, the discrimination accuracy of the mixed liquor samples of Guojiao 1573 and Luzhou Laojiao-Tequ is 92%, and the discrimination accuracy of the mixed liquor samples of Moutai and Moutai Prince is 100%, as shown in Figure 2. Fig.13 shown.

[0110] The embodiments of the present invention are described in detail above, but the present invention is not limited to the above embodiments. In addition, all equivalent changes and modifications made without departing from the method and scope of the present invention should be included in the scope of the present invention.

Claims

1. A method for identifying small organic molecules based on 4-aminoantipyrine, aromatic phenol and copper ions, characterized in that: The following steps are involved: A. Mixing a solvent, 4-aminoantipyrine, aromatic phenol A and copper ions to obtain an identification system A; mixing a solvent, 4-aminoantipyrine, aromatic phenol B and copper ions to obtain an identification system B; B. Adding the organic small molecule solution to the identification system A to obtain sample group A, adding the organic small molecule solution to the identification system B to obtain sample group B, and using an equal volume of the solvent used for the organic small molecule solution as a control; C. Record the fingerprints of sample group A, sample group B and control group, extract the R, G and B values ​​of sample group A, sample group B and control group, subtract the R, G and B values ​​of the corresponding control group from the R, G and B values ​​of the sample group to obtain the R, G and B difference of the organic small molecule; Qualitative analysis: Perform linear discriminant analysis on the R, G and B differences, perform qualitative analysis based on the results of linear discriminant analysis, and / or obtain a color difference diagram based on the R, G and B differences, and identify with the naked eye; Quantitative analysis: The Euclidean distance is calculated by the difference of R, G and B of the organic small molecules in sample group A and sample group B, and the total Euclidean distance is obtained by adding the calculated Euclidean distances of sample group A and sample group B. The standard curve is plotted with the logarithm of the organic small molecule concentration as the abscissa and the total Euclidean distance as the ordinate to obtain a linear equation, and quantitative analysis is performed using the standard curve and the linear equation; In step A, the aromatic phenol A is catechol, 3-aminophenol, 4-aminophenol, m-methylphenol, 4-methylphenol, 2-aminophenol, 3-aminophenol, 4-aminophenol or 2-methylaminophenol, the aromatic phenol B is catechol, 3-aminophenol, 4-aminophenol, m-methylphenol, 4-methylphenol, 2-aminophenol, 3-aminophenol, 4-aminophenol or 2-methylaminophenol, and the aromatic phenol A and aromatic phenol B are different; In step A, the solvent is at least one of water or ethanol; When it is a qualitative analysis, the following conditions are met: The organic small molecules are 7 carboxylic acids and 4 aldehydes and ketones, specifically at least one of acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid, octanoic acid, acetaldehyde, furfural, 2,3-butanedione or 3-hydroxy-2-butanone; in step B, the solvent used for the organic small molecule solution is at least one of water, ethanol or liquor; When performing quantitative analysis, the following conditions must be met: The organic small molecules are 7 carboxylic acids and 4 aldehydes and ketones, specifically acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, hexanoic acid, octanoic acid, acetaldehyde, furfural, 2,3-butanedione or 3-hydroxy-2-butanone; in step B, the solvent used for the organic small molecule solution is at least one of water or ethanol.

2. The organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion as claimed in claim 1, characterized in that: In step B, at least one of the following is met: After adding the organic small molecule solution to the identification system A, react for 10 to 20 minutes; After adding the organic small molecule solution to the identification system B, react for 10 to 20 minutes; The concentration of the organic small molecules in the sample group A and the sample group B is 0.00025-25 mmol / L.

3. The organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion as claimed in claim 1, characterized in that: In step B, at least one of the following is met: The concentration of 4-aminoantipyrine in the sample group A is 0.5-5 mmol / L; The concentration of 4-aminoantipyrine in the sample group B is 0.5-5 mmol / L.

4. The organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion as claimed in claim 1, characterized in that: In step B, at least one of the following is met: The concentration of aromatic phenol A in the sample group A is 0.5-5 mmol / L; The concentration of aromatic phenol B in the sample group B is 0.5-5 mmol / L.

5. The organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion as claimed in claim 1, characterized in that: At least one of the following is met: In step A, the copper ions are derived from at least one of copper nitrate, copper sulfate or copper chloride; In step B, the copper ion concentration in the sample group A is 0.5-5 mmol / L; In step B, the copper ion concentration in the sample group B is 0.5-5 mmol / L.

6. The organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion as claimed in claim 1, characterized in that: In step B, at least one of the following is met: The molar concentration ratio of 4-aminoantipyrine: aromatic phenol A: copper ion in the sample group A is 1-2: 1-2: 1-2; The molar concentration ratio of 4-aminoantipyrine: aromatic phenol B: copper ion in the sample group B is 1-2: 1-2: 1-2.

7. The organic small molecule identification method based on 4-aminoantipyrine, aromatic phenol and copper ion as claimed in claim 1, characterized in that: At least one of the following is met: When qualitative analysis is performed and the color difference diagram is obtained, the difference between R, G and B is magnified by 2 to 6 times; When quantitatively analyzed, the linear equation obtained is as follows: Where Y is the total Euclidean distance, and logC is the logarithm of the concentration of organic small molecules.

8. A liquor identification method based on 4-aminoantipyrine, aromatic phenol and copper ion, characterized in that: Based on the qualitative analysis step of the identification method described in any one of claims 1 to 7, the organic small molecule solution is replaced with liquor, and an equal volume of Vol 40-70% ethanol aqueous solution is used as a control.

Images