Method for detecting concentration of choline chloride by using near infrared spectrum

Abstract

The invention provides a method for detecting the concentration of choline chloride by using a near infrared spectrum. The method comprises the following steps: 1) preparing a plurality of choline chloride standard solutions with different concentrations; 2) performing spectrum acquisition on the choline chloride standard solution by using a near infrared spectrometer, and storing near infrared spectrum data; (3) establishing a mathematical model between the near infrared spectrum data of the modeling group and the concentration of the choline chloride standard solution by adopting a partial least square method; 4) importing the near infrared spectrum data of the verification group into the mathematical model for verification and correction; and 5) carrying out spectrum acquisition on a choline chloride solution to be detected, and then calculating by the mathematical model to output the concentration of the choline chloride solution. Quantitative analysis of the concentration of the choline chloride solution is achieved, the defects of a traditional detection method are overcome, and simple, convenient, rapid, accurate and real-time detection of the concentration of choline chloride is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of near-infrared spectroscopy concentration detection, and in particular to a method for detecting choline chloride concentration by utilizing near-infrared spectroscopy. Background Art

[0002] Choline chloride is an organic compound with the chemical formula C5H14ClNO. It is a white, hygroscopic crystal that is odorless with a fishy odor and a melting point of 305°C. It is soluble in water and ethanol, but insoluble in ether, petroleum ether, benzene, and carbon disulfide. It has low toxicity and is used to treat fatty liver and cirrhosis. It is also used as a livestock feed additive to stimulate ovarian production, increase egg production, and increase weight gain in livestock, fish, and other animals. As an important chemical raw material and feed additive, choline chloride has a wide range of applications in agriculture, medicine, and chemical engineering. Accurately measuring choline chloride concentration is crucial for ensuring product quality, controlling production processes, and ensuring the safe operation of related industries.

[0003] At present, there are many methods for detecting choline chloride concentration, such as Reinecke's salt colorimetry, non-aqueous titration, potentiometric titration, etc. However, these traditional methods have some limitations. For example, the Reinecke salt colorimetry has complicated operation steps, requires the use of multiple chemical reagents, and is easily interfered by other impurities, resulting in poor accuracy and repeatability of the test results; the non-aqueous titration method has strict requirements on experimental conditions, the judgment of the titration end point is highly subjective, and different operators may obtain different results; the potentiometric titration method requires the use of special electrodes, the maintenance and calibration of the electrodes are relatively complicated, and the detection cost is relatively high. In addition, most of these traditional methods are offline detection, which cannot achieve real-time, online monitoring, and it is difficult to meet the needs of modern industrial production for fast and accurate detection.

[0004] As a rapid, non-destructive, and environmentally friendly analytical technique, near-infrared spectroscopy has been widely used in recent years in fields such as chemistry, biology, and food. The near-infrared spectral region primarily reflects the vibrational harmonics and summed frequencies of hydrogen-containing groups (such as CH, NH, and OH) in organic molecules. Different substances exhibit distinct absorption characteristics in the near-infrared spectral region due to differences in their molecular structure. By collecting and analyzing a sample's near-infrared spectrum, qualitative and quantitative analysis of various components within the sample can be achieved. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for detecting the concentration of choline chloride using near-infrared spectroscopy, so as to solve the problems of the existing choline chloride concentration detection method, such as complicated operation, poor accuracy, and inability to detect in real time.

[0006] In order to solve the above technical problems, the technical solution provided by the present invention is:

[0007] A method for detecting choline chloride concentration using near-infrared spectroscopy comprises the following steps performed in sequence:

[0008] 1) preparing multiple choline chloride standard solutions of different concentrations, and then calibrating their concentrations in the laboratory;

[0009] 2) Near-infrared spectrometer acquisition: Use a near-infrared spectrometer to acquire the spectrum of the choline chloride standard solution, sequentially acquire choline chloride standard solutions of different concentrations and save the near-infrared spectral data;

[0010] 3) Establishing a mathematical model: The collected near-infrared spectral data of the choline chloride standard solution were randomly divided into two data groups, one data group was used as a modeling group for establishing the mathematical model, and the other data group was used as a validation group for validation;

[0011] A mathematical model between the near-infrared spectral data of the modeling group and the concentration of the choline chloride standard solution is established using partial least squares method;

[0012] 4) Verification and calibration: Import the near-infrared spectral data of the validation group into the mathematical model to verify and calibrate the mathematical model;

[0013] 5) Using a near-infrared spectrometer to collect a spectrum of the choline chloride solution to be measured, and then importing the collected near-infrared spectrum data into a mathematical model, and then the mathematical model outputs the concentration of the choline chloride solution to be measured after calculation.

[0014] Preferably, in step 1), the mass percentage concentration of the choline chloride standard solution is 60%-81%.

[0015] Preferably, the near-infrared spectrometer is preheated and calibrated before collecting the spectrum to ensure the stability and accuracy of the instrument. The scanning wavelength of the near-infrared spectrometer is 250-1700 nm.

[0016] Preferably, before establishing the mathematical model, the near-infrared spectral data is preprocessed and the noise is eliminated by using Savitzky-Golay smoothing filter;

[0017] The model parameters including the number of principal components are optimized through cross-validation method to improve the accuracy and stability of the mathematical model.

[0018] This application has achieved the following beneficial technical effects:

[0019] The present application applies near-infrared spectroscopy to the detection of choline chloride concentration. First, a mathematical model is established using one set of standard solution data and the partial least squares method. Then, the mathematical model is verified and calibrated using another set of standard solution data. Then, the verified and calibrated mathematical model is used to perform actual detection of the choline chloride solution to be tested. By collecting and analyzing the near-infrared spectrum of the choline chloride solution to be tested, quantitative analysis of the concentration of the choline chloride solution to be tested can be achieved. This overcomes the shortcomings of traditional detection methods and achieves simple, rapid, accurate, and real-time detection of choline chloride concentration. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is the near infrared spectra of choline chloride standard solutions with different concentrations;

[0021] Figure 2 This is a comparison chart of the predicted values ​​of the mathematical model established by the partial least squares method and the measured values ​​(measured values ​​determined by the detection method in the prior art), with the horizontal axis being the known measured values ​​and the vertical axis being the predicted values. DETAILED DESCRIPTION

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0023] The present application provides a method for detecting the concentration of choline chloride using near-infrared spectroscopy, comprising the following steps performed in sequence:

[0024] 1) preparing multiple choline chloride standard solutions (aqueous solutions) of different concentrations, and then calibrating their concentrations in the laboratory (the concentrations of the choline chloride standard solutions are known);

[0025] 2) Near-infrared spectrometer acquisition: Use a near-infrared spectrometer to acquire the spectrum of the choline chloride standard solution, sequentially acquire choline chloride standard solutions of different concentrations and save the near-infrared spectral data;

[0026] 3) Establishing a mathematical model: The collected near-infrared spectral data of the choline chloride standard solution were randomly divided into two data groups, one data group was used as a modeling group for establishing the mathematical model, and the other data group was used as a validation group for validation;

[0027] A mathematical model between the near-infrared spectral data of the modeling group and the concentration of the choline chloride standard solution is established using partial least squares method;

[0028] 4) verification and correction: the near infrared spectrum data of the verification group is introduced into the mathematical model to verify and correct the mathematical model;

[0029] 5) using the near infrared spectrometer to collect the spectrum of the measured choline chloride solution, then introducing the collected near infrared spectrum data into the mathematical model, and then the mathematical model outputs the concentration of the measured choline chloride solution after calculation.

[0030] In an embodiment of the present application, in step 1), the mass percentage concentration of the choline chloride standard solution is 60%-81%.

[0031] In an embodiment of the present application, the near infrared spectrometer is preheated and calibrated before collecting the spectrum to ensure the stability and accuracy of the instrument, and the scanning wavelength of the near infrared spectrometer is 250-1700nm.

[0032] In an embodiment of the present application, before establishing the mathematical model, the near infrared spectrum data is pretreated, and Savitzky-Golay smoothing filter is used to eliminate noise.

[0033] The model parameters including the number of principal components are optimized by the cross-validation method to improve the accuracy and stability of the mathematical model.

[0034] In the present application, Figure 1 The near infrared spectrum of the choline chloride standard solution with different concentrations is shown in Fig. Figure 1 It can be seen from the figure that with the change of the concentration of choline chloride, the absorption intensity of the near infrared spectrum at some characteristic wavelengths changes obviously.

[0035] Figure 2 The comparison chart of the predicted value and the measured value of the mathematical model established by the partial least squares method is shown in Fig. Figure 2 It can be seen from the figure that the predicted value and the measured value have a good linear relationship, indicating that the mathematical model has high detection accuracy.

[0036] The methods and devices not described in detail in the present application are prior art and will not be described again.

[0037] In order to further understand the present application, a method for detecting the concentration of choline chloride by using near infrared spectrum provided by the present application is described in detail below, and the protection scope of the present application is not limited by the following examples.

[0038] Example 1

[0039] A method for detecting the concentration of choline chloride by using near infrared spectrum, comprising the following steps in sequence:

[0040] 1) Preparing multiple choline chloride standard solutions of different concentrations and then calibrating their concentrations in the laboratory;

[0041] In step 1), the mass percentage concentration of the choline chloride standard solution is 60%-81%;

[0042] 2) Near-infrared spectrometer acquisition: Use a near-infrared spectrometer to acquire the spectrum of the choline chloride standard solution, sequentially acquire choline chloride standard solutions of different concentrations and save the near-infrared spectral data;

[0043] Before collecting the spectrum, the near-infrared spectrometer was preheated and calibrated to ensure the stability and accuracy of the instrument. The scanning wavelength of the near-infrared spectrometer was 250-1700 nm;

[0044] 3) Establishing a mathematical model: The collected near-infrared spectral data of the choline chloride standard solution were randomly divided into two data groups, one data group was used as a modeling group for establishing the mathematical model, and the other data group was used as a validation group for validation;

[0045] A mathematical model between the near-infrared spectral data of the modeling group and the concentration of the choline chloride standard solution is established using partial least squares method;

[0046] Before establishing the mathematical model, the near-infrared spectral data were preprocessed and the Savitzky-Golay smoothing filter was used to eliminate noise;

[0047] Optimize model parameters including the number of principal components through cross-validation to improve the accuracy and stability of the mathematical model;

[0048] 4) Verification and calibration: Import the near-infrared spectral data of the validation group into the mathematical model to verify and calibrate the mathematical model;

[0049] 5) Using a near-infrared spectrometer to collect a spectrum of the choline chloride solution to be measured, and then importing the collected near-infrared spectrum data into a mathematical model, and then the mathematical model outputs the concentration of the choline chloride solution to be measured after calculation.

[0050] 1.1 Accuracy Experiment

[0051] Table 1. Experimental data of the accuracy of the detection method of the present invention

[0052] Measured value / wt% Predicted value / wt% Absolute error / % Relative error / % Sample 1 61.9200％ 62.2700％ 0.3500％ 0.565％ Sample 2 65.3200％ 65.1185％ -0.2015％ 0.308％ Sample 3 67.4600％ 67.6232％ 0.1632％ 0.242％ Sample 4 69.8300％ 69.5959％ -0.2341％ 0.335％ Sample 5 71.0300％ 71.4323％ 0.4023％ 0.566％ Sample 6 75.7600％ 75.7884％ 0.0284％ 0.037％ Sample 7 79.2200％ 79.3456％ 0.1256％ 0.159％ Sample 8 80.9700％ 81.0459％ 0.0759％ 0.094％

[0053] The accuracy test of the choline chloride solution was carried out using the detection method provided by the present invention, and the results are shown in Table 1. As can be seen from the results in Table 1, the accuracy of the detection method is high.

[0054] 1.2 Precision experiment

[0055] Samples 9-13 of the same choline chloride solution were taken and tested respectively according to the same detection method of the present application as in Example 1. The test results are shown in Table 2.

[0056] Table 2 Experimental data of the precision of the detection method of the present invention

[0057] Measured value / wt% Predicted value / wt% Absolute error / % Relative error / % Sample 9 64.0800％ 63.6403％ -0.4397％ 0.686％ Sample 10 64.0800％ 64.4139％ 0.3339％ 0.521％ Sample 11 64.0800％ 64.0966％ 0.0166％ 0.026％ Sample 12 64.0800％ 63.9612％ -0.1188％ 0.185％ Sample 13 64.0800％ 64.5104％ 0.4304％ 0.672％

[0058] The choline chloride content in samples 9 to 13 was measured five times in parallel using the detection method provided by the present invention. The results are shown in Table 2. As can be seen from the results in Table 2, the detection method provided by the present invention can accurately determine the choline chloride content in the choline chloride solution with high repeatability, indicating that the detection method has high precision.

[0059] The above embodiments are only intended to help understand the method and core concept of the present invention. It should be noted that, without departing from the principles of the present invention, a number of improvements and modifications may be made to the present invention by those skilled in the art, and such improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A method for detecting choline chloride concentration using near-infrared spectroscopy, characterized in that: The method includes the following steps: 1) preparing multiple choline chloride standard solutions of different concentrations, and then calibrating their concentrations in the laboratory; 2) Near-infrared spectrometer acquisition: Use a near-infrared spectrometer to acquire the spectrum of the choline chloride standard solution, sequentially acquire choline chloride standard solutions of different concentrations and save the near-infrared spectral data; 3) Establishing a mathematical model: The collected near-infrared spectral data of the choline chloride standard solution were randomly divided into two data groups, one data group was used as a modeling group for establishing the mathematical model, and the other data group was used as a validation group for validation; A mathematical model between the near-infrared spectral data of the modeling group and the concentration of the choline chloride standard solution is established using partial least squares method; 4) Verification and calibration: Import the near-infrared spectral data of the validation group into the mathematical model to verify and calibrate the mathematical model; 5) Using a near-infrared spectrometer to collect a spectrum of the choline chloride solution to be measured, and then importing the collected near-infrared spectrum data into a mathematical model, and then the mathematical model outputs the concentration of the choline chloride solution to be measured after calculation.

2. A method for detecting choline chloride concentration using near-infrared spectroscopy according to claim 1, characterized in that, In step 1), the mass percentage concentration of the choline chloride standard solution is 60%-81%.

3. A method for detecting choline chloride concentration using near-infrared spectroscopy according to claim 1, characterized in that: Before collecting the spectrum, the near-infrared spectrometer was preheated and calibrated to ensure the stability and accuracy of the instrument. The scanning wavelength of the near-infrared spectrometer was 250-1700 nm.

4. A method for detecting choline chloride concentration using near-infrared spectroscopy according to claim 1, characterized in that, Before establishing the mathematical model, the near-infrared spectral data were preprocessed and the Savitzky-Golay smoothing filter was used to eliminate noise; The model parameters including the number of principal components are optimized through cross-validation method to improve the accuracy and stability of the mathematical model.

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