Method and device for determining biological origin

Abstract

To provide a method and device for determining biological origin, which can determine biological origin through simple steps, regardless of the form of an object.SOLUTION: A method for determining a biological component by measuring the radioactivity of radioactive carbon contained in a sample, comprises: a combustion step of combusting the sample; a measurement sample preparation step of contacting the carbon dioxide gas obtained by the combustion step with a measurement reagent for determining a biological component containing a carbon dioxide reactive group-containing compound as a main component to prepare a measurement sample; and a detection step of dispersing the obtained measurement sample in a scintillator cocktail to prepare a dispersion solution, and using the dispersion solution to detect C14 with a liquid scintillator.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a biological origin determination method and a biological origin determination device that can accurately and easily determine whether or not a substance contains a biological origin component using a simple device. [Background technology]

[0002] In recent years, efforts have been made to move away from fossil fuels and to use bio-derived components in fuels and other products. There is a need to determine whether or not these bio-derived components are present. Methods for determining whether or not a substance is bio-derived can be divided into two types: (1) accelerator mass spectrometry and (2) liquid scintillation spectrometry. Method (1) is more accurate and is more widely used, but the problem is that the equipment itself costs several hundred million yen, making it expensive to measure, and there are only a few of these devices available, making it difficult to measure. As for method (2), various methods for determining bio-derived components that utilize liquid scintillation spectrometry have been proposed, as the equipment can be prepared relatively inexpensively. For example, Patent Document 1 proposes an accurate and simple method for measuring bioethanol in hydrocarbon-based automobile fuel containing plant-derived ethanol. Specifically, water is added to a sample of hydrocarbon-based automobile fuel containing plant-derived ethanol, and the mixture is allowed to stand. After that, an extraction operation is performed to obtain the aqueous phase, which is separated into two layers. 14 A method for measuring the plant-derived ethanol content in hydrocarbon-based motor fuels by analyzing the carbon content has been proposed. In addition, Patent Document 2 describes the radioactive carbon ( 14 A method has been proposed for determining the biomass origin of plastics by measuring radioactivity (C) in the solid state using the LSC method. Specifically, the method involves immersing solid plastic in a liquid scintillator containing a solvent as an aromatic compound and a fluorescent substance, allowing the solvent to penetrate into the amorphous region of the solid plastic and measuring the radioactivity, thereby determining the biomass origin of the solid plastic. Patent Document 3 proposes evaluating the amount of biomass waste in waste when producing chemical products from waste. Specifically, the proposed device includes a chemical product content acquisition unit that acquires the carbon-14 content in the chemical product, and a biomass amount evaluation unit that evaluates the amount of biomass waste in the waste based on the carbon-14 content in the chemical product acquired by the chemical product content acquisition unit. Furthermore, Non-Patent Document 1 proposes purifying biodiesel fuel using a column chromatograph and measuring the carbon-14 content in the fuel using liquid scintillation measurement, and Non-Patent Document 2 proposes directly measuring the carbon-14 content in bioethanol gasoline using liquid scintillation measurement with only a simple concentration procedure. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-297489 [Patent Document 2] Japanese Patent Application Laid-Open No. 2014-132255 [Patent Document 3] Japanese Patent Application Laid-Open No. 2014-166622 [Non-patent literature]

[0004] [Non-Patent Document 1] Masaaki Saito, "Radiocarbon Measurement of Biodiesel Fuel Using a Liquid Scintillation Counter," Radioisotopes, Japan Radioisotope Association, July 15, 2009, Vol. 58(7), pp. 455-460 [Non-patent document 2] Masaaki Saito and two others, "Technology for Determining the Origin of Biofuels Using Natural Radioactive Carbon C-14," Research Report, Tokyo Metropolitan Industrial Technology Research Institute, December 22, 2009, No. 4, pp. 16-19 Summary of the Invention [Problem to be solved by the invention]

[0005] However, all of the above proposals are limited to certain targets or require complicated pretreatment, and the current situation is that it is not possible to determine the biological origin of any target object in a simple process, regardless of its form. Therefore, an object of the present invention is to provide a biological origin determination method and a biological origin determination device that can determine whether an object is biologically originated through simple steps, regardless of the form of the object. [Means for solving the problem]

[0006] As a result of intensive research to solve the above problems, the inventors discovered that by using a specific measurement reagent, it is possible to determine whether a substance is of biological origin using a process that is simpler than conventional methods, and have thus completed the present invention. That is, the present invention provides the following inventions. 1. A method for determining biological components by measuring the radioactivity of radioactive carbon contained in a sample, a combustion step of combusting the sample; a measurement sample preparation step of contacting the carbon dioxide gas obtained by the combustion step with a measurement reagent for determining a biological component containing a carbon dioxide reactive group-containing compound as a main component to prepare a measurement sample; a detection step in which the obtained measurement sample is dispersed in a scintillator cocktail to prepare a dispersion solution, and the dispersion solution is used to detect C14 using a liquid scintillator; A method for determining a biological component, comprising: 2. The method for distinguishing a biological component according to 1, wherein the concentration of the measurement sample in the scintillator cocktail is 3 to 7 g / 10 ml. 3. A calibration curve creation step is provided in which a calibration curve is created using a plurality of measurement samples in which the blending ratio (wt%) of the bio-derived component is changed in advance; The proportion of bio-derived components can be quantitatively calculated. 1. A method for determining a biologically derived component according to claim 1. 4. The method for determining a biologically derived component according to 1, wherein the carbon dioxide reactive group-containing compound is a basic group-containing compound, and the basic group is a nitrogen-containing substituent. 5. The method for determining a biological component according to 1, wherein the carbon dioxide reactive group-containing compound is at least one selected from the group consisting of ammonia, diamine compounds, and heterocycle-containing compounds. An apparatus for carrying out the method for determining biological components according to 6.1, a combustion unit that combusts a sample to be measured; a reaction chamber in which the carbon dioxide gas in the gas obtained by combustion reacts with a measurement reagent for determining biological components; A biological component discrimination device comprising: [Effects of the Invention]

[0007] According to the biological origin determination method and biological origin determination device of the present invention, biological origin determination can be performed through simple steps, regardless of the form of the object. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is an explanatory diagram showing the main parts of the biological origin determination device of the present invention. [Figure 2] Figure 2 is a chart showing the relationship between weight and detected radiation dose for comparative petroleum products and bio-based products. [Figure 3] Figure 3 is a chart (calibration curve chart) showing the detected radiation doses of several types of measurement samples with different proportions of biologically derived components. [Explanation of symbols]

[0009] 1 Biological component discrimination device, 10 Combustion section, 11 Sample, 13 Tubular furnace, 15 Heating section, 17 Oxygen etc. supply path, 20 Cooling section, 21 Transfer pipe, 30 Drying section, 40 Reaction chamber, 41 Gas transfer pipe, 43 Exhaust pipe, 45 Measurement reagent solution DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be explained in more detail below, but the present invention is not limited thereto. Hereinafter, first, the reagent for determining a biologically derived component used in the method for determining a biologically derived component of the present invention will be described, and then the device for carrying out the method for determining a biologically derived component and the method for determining a biologically derived component of the present invention will be described. <Biological origin determination measurement reagents> The measurement reagent for determining biological components (hereinafter simply referred to as "measurement reagent") used in the determination method of the present invention is a measurement reagent used in the biological determination method for measuring the radioactivity of radiocarbon contained in a sample, and is characterized by containing a carbon dioxide reactive group-containing compound as its main component. Here, bio-derived components refer to fuels, plastics, etc. produced using biological resources as raw materials. In recent years, various biofuels and bioplastic processed products have been proposed from the perspective of zero emissions. However, when measuring the extent to which bio-derived components are used in commercially available biofuels, etc., or whether they are actually used, it is necessary to consider the C 14 By measuring this, it becomes possible to determine whether the material in question (including fuel) is bio-derived or not.

[0011] [Compound containing carbon dioxide reactive group] The carbon dioxide-reactive group-containing compound used as the main component of the measuring reagent in the present invention is a compound having a carbon dioxide-reactive group. Carbon dioxide-reactive means that it can react with carbon dioxide. The carbon dioxide reactive group-containing compound is preferably a basic group-containing compound, and examples of the basic group include nitrogen-containing substituents. Specifically, the carbon dioxide reactive group-containing compound can be one or more compounds selected from the group consisting of ammonia, diamine compounds, and heterocyclic ring-containing compounds. Examples of diamine compounds include ethylenediamine, diaminopropane, diaminobutane, N,N'-dimethylethylenediamine, 1,2-diaminocyclopentane, 1,2-diaminocyclohexane, and hydrazine. Examples of heterocyclic ring-containing compounds include piperazine, imidazolidine, pyrazolidine, 2-pyrazoline, 3-pyrazoline, imidazole, triazole, pyrazole, and imidazoline. These compounds can be used alone or in combination. [Other ingredients] Furthermore, other components may be added to the measuring reagent of the present invention as long as they do not inhibit the function of the carbon dioxide reactive compound. In particular, to dissolve the test reagent and react it with carbon dioxide in the gas obtained by burning the sample, it is preferable to use the test reagent as a solution in a solvent. Examples of solvents that can be used in this case include alcohols such as methanol, ethanol, and isopropanol, as well as water, acetone, acetonitrile, and tetrahydrofuran. The amount of solvent used is preferably such that the test reagent concentration is 100 g / L or more.

[0012] [How to use] The measurement reagent of the present invention can be used by carrying out the following method for distinguishing a biological component using the following device for distinguishing a biological component. Each of these will be explained below.

[0013] <Biological origin determination device> As shown in FIG. 1, the biological component discrimination device 1 according to one embodiment of the present invention for use with the measurement reagent of the present invention comprises a combustion unit 10 for combusting a sample to be measured; The apparatus is provided with a reaction chamber 40 in which the carbon dioxide gas in the gas obtained by combustion is reacted with the above-mentioned biological origin determination reagent. More specifically, the combustion section 10 includes a tubular furnace 13 in which a sample 11 to be measured is placed and in which the sample 11 is burned, a heating section 15 for heating the tubular furnace 13, and an oxygen supply path 17 arranged at one end of the tubular furnace 13 for supplying oxygen and nitrogen to the tubular furnace 13. A transfer pipe 21 is provided at the other end of the tubular furnace 13 for transferring gas (mainly CO2 and HO) generated by combustion in the combustion section 10, and the transfer pipe 21 passes through water provided in the cooling section 20 and is connected to the drying section 30. Calcium chloride is provided in the drying section 30, and the gas mixed with nitrogen gas has moisture removed and is dried by passing through the drying section provided with calcium chloride. A gas transfer pipe 41 is connected to the drying section 30, and the end of the gas transfer pipe 41 is immersed in the reaction solution containing the test reagent in the reaction chamber 40. The reaction chamber 40 is sealed, and the gas transferred by the gas transfer pipe 41 is released to the outside through an exhaust pipe 43 located at the top. In this embodiment, the reaction chamber 40 is filled with a measurement reagent solution 45 in which ethylenediamine is dissolved in ethanol as a measurement reagent. The biological component discrimination device 1 of this embodiment is equipped with a liquid scintillator (not shown), and is capable of discriminating between biological components by performing scintillation using a measurement sample 50 produced by the liquid scintillator. There are no particular limitations on the liquid scintillator that can be used, and any commonly used liquid scintillation device can be used. Specifically, the biologically derived component can be identified by carrying out the following method for identifying the biologically derived component.

[0014] <Method for identifying bio-derived ingredients> The method for determining a biological component of this embodiment is a method for determining a biological component by measuring the radioactivity of radioactive carbon contained in a sample, and can be carried out by carrying out the following steps: a combustion step in which the sample is combusted; a measurement sample preparation step in which carbon dioxide gas obtained by the combustion step is brought into contact with the above-mentioned measurement reagent for determining biological origin to prepare a measurement sample; and a detection step in which the obtained measurement sample is dispersed in a scintillator cocktail to prepare a dispersion solution, and C14 is detected using the dispersion solution with a liquid scintillator.

[0015] [Combustion process] The combustion step is carried out by burning the sample 11 in the above-mentioned combustion unit 10 to produce a gas containing carbon dioxide. The combustion temperature is arbitrary depending on the type of the sample 11.

[0016] [Measurement sample preparation process] In this embodiment, the gas obtained by the combustion step is passed through a cooling section 20 to be cooled, and is passed through a drying section 30 to remove moisture. The dried gas is then injected into the test reagent solution 45 in the reaction chamber 40, whereby ethylenediamine as a test reagent in the test reagent solution 45 reacts with carbon dioxide in the gas to produce ammonium carbamate. In this way, this step can be carried out by reacting a solution containing the test reagent with carbon dioxide contained in the gas obtained by burning the sample. Here, the carbon dioxide and the test reagent can be reacted by mixing the gas into the test reagent solution to produce the test sample.

[0017] [Detection step] The detection step can be carried out by dispersing the obtained measurement sample in a scintillator cocktail to prepare a dispersion solution, and then performing scintillation using a liquid scintillator using the dispersion solution. The measurement sample is generated in the above-mentioned measurement reagent solution, but it usually precipitates as a solid and can be isolated by filtration. If it is dissolved, it can be isolated as a solid by performing a conventional reprecipitation treatment. The isolated measurement sample (ammonium carbamate in this embodiment) is dispersed in a scintillator cocktail. The scintillator cocktail that can be used in this case is preferably hydrophobic. Furthermore, the viscosity is preferably in the range of 0.20 to 2.00 cP. A specific example of a hydrophobic scintillator cocktail that satisfies the above viscosity is one in which 4 g of DPO (2,5-diphenyloxazole) and 0.1 g of POPOP (1,4-bis(5-phenyl-2-oxazolyl)benzene) are dissolved in 1 liter of a solvent (toluene:xylene=95:5). Alternatively, commercially available products such as Scintisol (registered trademark) AL-1 and ULTIMA GOLD (registered trademark) can also be used. Furthermore, the concentration of the measurement sample relative to the scintillator cocktail is preferably 2 to 10 g / 10 ml, and more preferably 3 to 7 g / 10 ml. At such a concentration, the measurement sample is not dissolved but precipitated and dispersed in the scintillator cocktail to form a dispersion. By forming the measurement sample into a highly concentrated dispersion, it has been conventionally believed that measurement is only possible with a solution in which the measurement sample is dissolved in a scintillator cocktail. However, the present inventors have found that measurement samples obtained using the above-described measurement reagent can be successfully measured by forming the measurement sample into a dispersion rather than a solution. Therefore, the concentration is preferably within the above range. Other liquid scintillation procedures are not particularly limited and known techniques can be used.

[0018] [Other steps] (Calibration curve creation process) Furthermore, in this embodiment, a calibration curve creation step is carried out in which a calibration curve is created using a plurality of measurement samples in which the blending ratio (wt %) of the bio-derived component is changed in advance, and the proportion of the bio-derived component can be quantitatively calculated. To create a calibration curve, first prepare samples with bio-derived component contents of 0%, 25%, 50%, 75%, and 100% by weight. Next, perform the above-mentioned steps on these samples to obtain liquid scintillation measurement results. The obtained results can be charted and a calibration curve can be created by plotting the results. By creating a calibration curve, quantitative analysis can be performed on an unknown sample by comparing the liquid scintillation measurement results obtained through each of the above steps with the calibration curve.

[0019] [Effects and uses] According to the biological component discrimination method of this embodiment, which performs the above-mentioned steps, the method is carried out using the above-mentioned measurement reagent of the present invention and the above-mentioned biological component discrimination device of this embodiment. Therefore, since a liquid scintillation counter is used instead of an accelerator mass spectrometer, it is relatively easy to introduce in terms of both cost and space. Pretreatment is completed in one step using only simple experimental procedures, making discrimination simpler and easier than conventional methods. Furthermore, discrimination can be performed regardless of the sample's form, regardless of whether it is liquid or solid. Furthermore, when a calibration curve creation step is performed, the content of the biological component can be estimated by comparison with a standard sample, so the content of the biological component can be calculated even if the radiation detection rate in liquid scintillation measurement is not 100%. Because of these effects, the method can be widely used to distinguish between bio-derived components in various products.

[0020] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention. [Example]

[0021] The present invention will be explained in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples at all. Example 1 (1) CO2 capture using ethanol solutions of amino-containing organic compounds PHBV (Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)) pellets were used as samples, and the determination was performed using the apparatus shown in Figure 1. Specifically, PHBV was placed in a tubular furnace 13 and burned under oxygen gas flow. The CO2 generated as a result was transferred to a reaction chamber 40 and mixed with a test reagent solution 45, where ethylenediamine and CO2 were brought into contact and reacted. This resulted in a white precipitate of ammonium carbamate, which served as the test sample, and was collected by suction filtration. The resulting test sample was dried under reduced pressure in a desiccator overnight. (2) Preparation of standard samples with known amounts of bio-derived components and liquid scintillation measurement Ammonium carbamate was synthesized using two carbon sources with known bio-based content and used as standard samples. The carbon source with 0 bio-based content was a CO2 spray can made from petroleum-derived carbon (hereafter referred to as "petroleum carbon"), and the carbon source with 100 bio-based content was air (hereafter referred to as "biomass carbon"). The synthesis method for each standard sample is as follows. Petroleum carbon standard sample A solution of ethylenediamine (5.0 mL) in ethanol (50 mL) was prepared. CO2 gas diluted with oxygen gas was gradually passed through the solution, and the reaction with ethylenediamine produced a white solid of ammonium carbamate. The resulting precipitate was collected by suction filtration and washed with ethanol. This was dried under reduced pressure in a desiccator overnight and used as the sample for measurement. Biomass standard sample Ethylenediamine (5.0 mL) was dispensed into a conical beaker. This was left to stand in a draft for 8 days to allow the ethylenediamine to react with atmospheric CO2. After 8 days, ethanol was added and the mixture was stirred, yielding a white precipitate of ammonium carbamate. The resulting precipitate was collected by suction filtration and washed with ethanol. This was then dried under reduced pressure in a desiccator overnight to prepare the sample for measurement. (3) Radioactivity comparison of standard samples The two standard samples were weighed out in amounts of 1.0 g, 2.0 g, 3.0 g, 4.0 g, and 5.0 g, respectively, and placed in low-potassium glass vials for liquid scintillation counter measurement. 10 ml of Scintisol® AL-1 was added as a scintillator cocktail, and the ammonium carbamate and scintillator cocktail were thoroughly mixed using an ultrasonic cleaner. A vial containing only the scintillator cocktail was also prepared as a sample for background (BG) measurement. The results of liquid scintillation counting of these standard samples are shown in Figure 2. The petroleum carbon standard samples show radioactivity values ​​that are independent of sample weight, and the radioactive isotope of carbon, C 14 On the other hand, in the biomass carbon standard sample, the radioactivity increases monotonically with increasing sample weight, indicating that radioactive carbon C 14 Therefore, the radioactivity value of the synthesized ammonium carbamate indicates that the organic sample contains radiocarbon C 14 It was shown that it is possible to determine whether or not a substance contains (4) Preparation of measurement vials for liquid scintillation counter (before the detection process) 5.0 g of the ammonium carbamate obtained in (1) and (2) above was weighed and placed in a low-potassium glass vial for liquid scintillation counter measurement. 10 mL of Scintisol (registered trademark) AL-1 was added as a scintillator cocktail, and the ammonium carbamate and the scintillator cocktail were thoroughly mixed using an ultrasonic cleaner to obtain a dispersion. (5) Creation of a biobased content calibration curve using standard samples and evaluation of the biobased content of unknown samples (post-detection process and quantitative analysis) Using the radioactivity measurements obtained from liquid scintillation spectrometry of the standard samples prepared in (2) above, a calibration curve chart was created by plotting biobased content against radioactivity (Figure 3). For samples with 25%, 50%, and 75% bio-derived content, the petroleum carbon standard sample and biomass standard sample were mixed at ratios of 3.75g / 1.25g, 2.5g / 2.5g, and 1.25g / 3.75g, respectively, and ground in a mortar for 10 minutes. A calibration curve was created by applying the least squares method to the five plots obtained in this way. The equation for the calibration curve was calculated as y = 0.058 * x + 1.94, where x is the bio-derived content and y is the radioactivity. Next, the radioactivity of 5.0 g of ammonium carbamate synthesized from PHBV pellets using method (1) above was measured. The radioactivity of this sample was measured three times, yielding values ​​of 7.53, 7.70, and 7.63 DPM (shown in Figure 3). Substituting these three measured radioactivity values ​​into the calibration curve equation, the bio-based content was calculated to be 96.2%, 99.2%, and 96.5%, respectively. To determine the precise bio-based content of the PHBV pellets, we outsourced accelerator mass spectrometry (ACCMS), a current method, and obtained a result of 98%. This demonstrates that this method has sufficient measurement accuracy.

Claims

1. A method for determining biological components by measuring the radioactivity of radioactive carbon contained in a sample, a combustion step of combusting the sample; a measurement sample preparation step of contacting the carbon dioxide gas obtained by the combustion step with a measurement reagent for determining a biological component containing a carbon dioxide reactive group-containing compound as a main component to prepare a measurement sample; a detection step in which the obtained measurement sample is dispersed in a scintillator cocktail to prepare a dispersion solution, and the dispersion solution is used to detect C14 using a liquid scintillator; A method for determining a biological component, comprising:

2. The concentration of the measurement sample in the scintillator cocktail is 3 to 7 g / 10 ml. The method for determining a biological component according to claim 1.

3. a calibration curve creation step of creating a calibration curve using a plurality of measurement samples in which the blending ratio (wt%) of the bio-derived component is changed in advance; The proportion of bio-derived components can be quantitatively calculated. The method for determining a biological component according to claim 1.

4. The carbon dioxide reactive group-containing compound is a basic group-containing compound, and the basic group is a nitrogen-containing substituent. The method for determining a biological component according to claim 1.

5. The carbon dioxide reactive group-containing compound is at least one selected from the group consisting of ammonia, diamine compounds, and heterocycle-containing compounds. The method for determining a biological component according to claim 1.

6. An apparatus for carrying out the method for determining a biological component according to claim 1, a combustion unit that combusts a sample to be measured; a reaction chamber in which the carbon dioxide gas in the gas obtained by combustion reacts with a measurement reagent for determining biological components; A biological component discrimination device comprising:

Images