Method for simultaneously determining content of 5-hydroxymethylfurfural and bis-(5-formyl furfuryl) ether

Abstract

The invention discloses a method for simultaneously measuring the content of 5-hydroxymethylfurfural and bis-(5-formyl furfuryl) ether, which comprises the following steps: sampling a 5-hydroxymethylfurfural crude product, and preparing a to-be-measured sample solution by taking methanol as a solvent; the method comprises the following steps: under chromatographic conditions, carrying out high performance liquid chromatography analysis and determination on a to-be-detected sample solution, respectively recording chromatographic peak areas of 5-hydroxymethylfurfural and bis-(5-formyl furfuryl) ether, and substituting the chromatographic peak areas into a standard curve equation of 5-hydroxymethylfurfural and bis-(5-formyl furfuryl) ether to obtain a 5-hydroxymethylfurfural and bis-(5-formyl furfuryl) ether standard curve equation and a 5-hydroxymethylfurfural and bis-(5-formyl furfuryl) ether standard curve equation. And calculating to obtain the content of the 5-hydroxymethylfurfural and the content of the bis-(5-formyl furfuryl) ether. Under the chromatographic condition, the retention time of determining and analyzing HMF and OBMF is 4.9 min and 7.76 min, and the separation degree of the method is Rgt; and 1.5, the impurity interference is avoided, and the content of HMF and OBMF in the HMF crude product can be accurately measured at the same time.

Description

Technical Field

[0001] The present invention belongs to the technical field of furan bio-based content determination, and more specifically, relates to a method for simultaneously determining the contents of 5-hydroxymethylfurfural (abbreviated as "HMF") and bis-(5-formylfurfuryl) ether (abbreviated as "OBMF") in a 5-hydroxymethylfurfural crude product. Background Art

[0002] 5-Hydroxymethylfurfural is a bio-based intermediate with an aromatic furan structure. It is a platform compound with high technical content, huge application potential, and clean and environmentally friendly characteristics. It is expected to lead the chemical industry from the "benzene era" to the cleaner and more environmentally friendly "furan era".

[0003] Bis-(5-formylfurfuryl) ether is a bio-based intermediate with an aromatic furan structure. It is a platform compound with high technical content, great application potential, and clean and environmentally friendly. Bis-(5-formylfurfuryl) ether exists in many plants. People have isolated this compound from hawthorn, honeysuckle, ganoderma lucidum, and chuanxiong. Pharmacological experiments have shown that it has antiviral, antioxidant and tuberculosis inhibitory effects. However, there are few studies on its synthesis. Larousse C. et al. reported that 5-hydroxymethylfurfural was catalytically dehydrated at high temperature (155°C) in DMSO to generate bis-(5-formylfurfuryl) ether. There are also reports that bis-(5-formylfurfuryl) ether was prepared using sucrose as the starting material through three simple reactions: acid dehydration, halogenation, hydrolysis, and room temperature dehydration.

[0004] In the crude product of 5-hydroxymethylfurfural, due to the presence of acid and water, its etherification product, namely bis-(5-formylfurfuryl) ether, is easily generated. That is, bis-(5-formylfurfuryl) ether is the most important by-product generated during the synthesis and storage of the crude 5-hydroxymethylfurfural. The determination of the content of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether in the crude 5-hydroxymethylfurfural is helpful to understand the quality changes of 5-hydroxymethylfurfural and provide a theoretical basis for the separation of the two. Summary of the invention

[0005] Technical issues

[0006] The present invention is designed to solve the above-mentioned problems in the prior art. The purpose of the present invention is to provide a method for simultaneously determining the contents of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether. The method can simultaneously and accurately determine the contents of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether in a crude 5-hydroxymethylfurfural product, and the operation is simple and quick, and the result is accurate.

[0007] Technical Solution

[0008] In order to achieve the above object, according to the present invention, the present invention provides a method for simultaneously measuring the content of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether, the method comprising:

[0009] The crude 5-hydroxymethylfurfural product was sampled and methanol was used as solvent to prepare the sample solution to be tested;

[0010] Under the following chromatographic conditions, the above-mentioned sample solution was subjected to high performance liquid chromatography analysis and determination, and the chromatographic peak areas of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether were recorded respectively;

[0011] Substitute the chromatographic peak areas of the above 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether into the standard curve equations of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether, respectively, and calculate the contents of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether,

[0012] The chromatographic conditions were as follows:

[0013] Chromatographic column: C18 column;

[0014] Mobile phase: methanol / water, gradient elution;

[0015] Detection wavelength: 260~300nm.

[0016] Beneficial Effects

[0017] The method for simultaneously determining the contents of HMF and OBMF of the present invention is simple and easy to operate. The retention times of HMF and OBMF determined and analyzed under the chromatographic conditions of the present invention are 4.9 min and 7.76 min. By comparing the retention times of the standard and sample chromatograms, it can be determined that the sample measured is HMF and OBMF. By calculating the separation degree R>1.5, there is no interference from impurities, and the method is highly feasible. The method can simultaneously and accurately determine the contents of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether in the crude 5-hydroxymethylfurfural product. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of this specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention.

[0019] In the attached picture:

[0020] Figure 1 is the standard curve of OBMF obtained in the embodiment of the present invention;

[0021] Figure 2 is the standard curve of HMF obtained in the embodiment of the present invention;

[0022] Figure 3HPLC spectrum of the OBMF standard obtained in the embodiment of the present invention;

[0023] Figure 4 HPLC spectrum of HMF standard obtained in the embodiment of the present invention;

[0024] Figure 5 HPLC spectrum of HMF and OBMF in the sample solution prepared by sampling the crude 5-hydroxymethylfurfural product;

[0025] Figure 6 The trend diagram of OBMF content change over time obtained by HPLC analysis of HMF crude products at different storage temperatures;

[0026] Figure 7 The HPLC spectrum obtained by HPLC analysis of the HMF crude product sample solution in Comparative Example 1;

[0027] Figure 8 This is the HPLC spectrum obtained by performing HPLC analysis on the HMF crude product sample solution in Comparative Example 2. DETAILED DESCRIPTION

[0028] Hereinafter, the method for simultaneously determining the contents of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether of the present invention will be described in more detail to help understand the present invention.

[0029] According to the present invention, the present invention provides a method for simultaneously measuring the content of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether, the method comprising:

[0030] The crude 5-hydroxymethylfurfural product was sampled and methanol was used as solvent to prepare the sample solution to be tested;

[0031] Under the following chromatographic conditions, the above-mentioned sample solution was subjected to high performance liquid chromatography analysis and determination, and the chromatographic peak areas of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether were recorded respectively;

[0032] Substitute the chromatographic peak areas of the above 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether into the standard curve equations of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether, respectively, and calculate the contents of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether,

[0033] The chromatographic conditions were as follows:

[0034] Chromatographic column: C18 column;

[0035] Mobile phase: methanol / water, gradient elution;

[0036] Detection wavelength: 260~300nm.

[0037] According to one embodiment of the present invention, the crude 5-hydroxymethylfurfural is a crude 5-hydroxymethylfurfural which is easily generated during the synthesis and storage of 5-hydroxymethylfurfural due to the presence of acid and water, and its etherification product, namely bis-(5-formylfurfuryl) ether, is formed.

[0038] According to one embodiment of the present invention, when preparing the sample solution to be tested, for example, weigh the HMF crude product, add methanol as a solvent, adjust the volume to a 100 ml volumetric flask after ultrasonic dissolution, ultrasonic dissolution, cool to room temperature and set aside, and filter through a 0.45 μm filter membrane before HPLC determination. The ultrasonic dissolution time can be 1 to 60 s, preferably 10 to 30 s; the mass of the HMF crude product can be 5 mg to 25 mg, preferably 10 mg to 15 mg.

[0039] According to one embodiment of the present invention, the above-mentioned sample solution is subjected to high performance liquid chromatography analysis under the following chromatographic conditions, and the chromatographic peak areas of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether are recorded respectively. The chromatographic conditions are as follows:

[0040] Chromatographic column: C18 column;

[0041] Mobile phase: methanol / water, gradient elution;

[0042] Detection wavelength: 260~300nm.

[0043] The C18 chromatographic column is an octadecylsilane bonded silica gel chromatographic column, such as Agilent ZORBAXExtend C18, 4.6x250mm, 5μm HPLC column, or other equivalent C18 column.

[0044] The mobile phase can be methanol / water, and the gradient elution method can be as follows:

[0045] Time / min Methanol / volume % Water / volume % 0min 5 95 10min 100 0 15min 5 95 17min 5 95

[0046] When performing high performance liquid chromatography detection, the flow rate may be 0.4 to 2 mL / min, specifically, 1 mL / min.

[0047] When performing high performance liquid chromatography detection, the injection volume can be 5 μL to 20 μL, specifically, can be 10 μL.

[0048] When performing high performance liquid chromatography detection, the column temperature can be 25°C to 60°C, specifically, can be 40°C.

[0049] When performing high performance liquid chromatography detection, the detection wavelength may be 260 to 300 nm, specifically, 278 nm.

[0050] According to one embodiment of the present invention, the chromatographic peak areas of the above-mentioned 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether are respectively substituted into the standard curve equations of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether to calculate the respective contents of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether. The standard curve equations of the 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether are obtained as follows: accurately weigh 5-hydroxymethylfurfural standard and bis-(5-formylfurfuryl) ether standard, use methanol as solvent, prepare a series of HMF standard solutions and OBMF standard solutions of different concentrations, perform high performance liquid chromatography under the same chromatographic conditions, and record the peak areas respectively; use the peak area as the ordinate and the concentration of the standard solution as the abscissa to draw a standard curve to obtain a regression equation.

[0051] Example

[0052] Below, the method for simultaneously measuring the contents of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether of the present invention is more specifically described by examples, but the protection scope of the present invention is not limited to these examples.

[0053] The experimental methods in the following examples are conventional methods unless otherwise specified. The experimental materials used in the following examples are commercially available unless otherwise specified.

[0054] 1 Experimental part

[0055] 1.1 Raw materials and medicines

[0056] HMF standard (HPLC purity> 99.8%, Zhejiang Tangneng Technology Co., Ltd.), HMF crude product (obtained under different storage conditions); methanol (AR, Shanghai Titan Technology Co., Ltd.); methanol (chromatographic grade, Shanghai Titan Technology Co., Ltd.); OBMF standard (HPLC purity> 99.5%, Zhejiang Tangneng Technology Co., Ltd.); purified water (Wahaha purified water);

[0057] 1.2 Experimental instruments and equipment

[0058] High performance liquid chromatograph: Agilent 1260 (including online degasser, quaternary pump, autosampler, column oven, UV detector, chromatographic workstation); Chromatographic column: ZORBAX Extend C18, 4.6x250mm, 5μm (Agilent); analytical balance 0.00001g (Mettler-Toledo Instrument Co., Ltd.); ultrasonic cleaner (Shanghai Kedao Ultrasonic Instrument Co., Ltd.);

[0059] 1.3 Principle of the method

[0060] The present invention adopts high performance liquid chromatography to obtain a trend diagram of the change of HMF and OBMF contents in the HMF crude product over time at different storage temperatures, and takes the above storage samples at a certain sampling time to measure and analyze them.

[0061] Weigh about 0.01 g of each of the above samples, record the exact mass, dissolve it with methanol and make up to 100 ml volumetric flask, ultrasonically dissolve it, cool it to room temperature, prepare the sample solution to be tested, filter it through a 0.45 μm filter membrane, and determine it by HPLC.

[0062] 1.4 Chromatographic conditions

[0063] Mobile phase: 0 min, methanol: water = 5:95; 10 min, methanol: water = 100:0; 15 min, methanol: water = 5:95, post-running time 2 min gradient elution, where the ratio of methanol to water is volume ratio;

[0064] Detection wavelength: 278nm;

[0065] Flow rate: 1.0 mL / min;

[0066] Injection volume: 10 μL;

[0067] Column temperature: 40°C;

[0068] 1.5 Drawing of OBMF and HMF standard curves

[0069] 1.5.1 Drawing of the standard curve of OBMF

[0070] (1) Accurately weigh 0.01444 g of OBMF and dissolve it in methanol into a 100 mL volumetric flask. Use ultrasonic dissolution to prepare a 0.1444 g / L standard stock solution.

[0071] (2) Take 6.25mL, 12.5mL, 25mL, and 50mL of the above mother solution and dilute them to a 100mL volumetric flask, respectively, to 0.009g / L, 0.0180g / L, 0.0361g / L, 0.0722g / L, and 0.1444g / L; a total of 5 standards with increasing concentrations. Perform analysis under the above chromatographic conditions, inject each sample twice, and record the peak area of ​​OBMF. Figure 3 As shown, Figure 3 This is the HPLC spectrum of OBMF standard.

[0072] (3) Draw a standard curve with the peak area Y (mAu) axis as the ordinate and the standard sample concentration X (g / L) axis as the abscissa, and perform regression processing.

[0073] Figure 1 is the standard curve of OBMF.

[0074] according to Figure 1 , the standard curve is: Y = 67621.3542X-10.3899, the correlation coefficient R 2 =0.99999. This indicates that within the concentration range of OBMF from 0.009 g / L to 0.1444 g / L, the chromatographic peak area is linearly related to the sample concentration.

[0075] 1.5.2 Drawing of the standard curve of HMF

[0076] (1) Accurately weigh 0.01312 g of HMF and dissolve it in methanol into a 100 mL volumetric flask. Use ultrasonic dissolution to prepare a 0.1312 g / L standard stock solution.

[0077] (2) Take 6.25mL, 12.5mL, 25mL, and 50mL of the above mother solution and dilute them to a 100mL volumetric flask, respectively, to 0.0082g / L, 0.0164g / L, 0.0328g / L, 0.0656g / L, and 0.1312g / L; a total of 5 standards with increasing concentrations. Analyze under the above chromatographic conditions, inject each sample twice, and record and calculate the average peak area of ​​HMF. Figure 4 As shown, Figure 4 HPLC spectrum of HMF standard.

[0078] (3) Draw a standard curve with the peak area Y (mAu) axis as the ordinate and the standard sample concentration X (g / L) axis as the abscissa, and perform regression processing.

[0079] Figure 2 is the standard curve of HMF.

[0080] according to Figure 2 , the standard curve is: Y = 71507.8513X + 14.4614, the correlation coefficient R 2 =0.99997. This indicates that within the concentration range of 0.0082 g / L to 0.1312 g / L, the chromatographic peak area is linearly related to the sample amount.

[0081] 1.6 Precision test

[0082] 1.6.1 Precision test of OBMF determination (n = 6)

[0083] Prepare a 1wt% methanol solution of OBMF, that is, weigh about 1g of OBMF, record the exact mass, dissolve it in methanol and make it up to 100ml in a volumetric flask, shake it well, and make the sample solution to be tested, filter it through a 0.45μm filter membrane, and repeat the measurement 6 times on a HPLC machine. After conversion, the OBMF content and the relative standard deviation (RSD) of OBMF were obtained.

[0084]

[0085] It can be seen from the above table that the OBMF content in the sample remains basically unchanged, and its RSD value is 0.0539%, which is less than 1%, indicating that the precision of determining OBMF using this method is relatively high.

[0086] 1.6.2 Precision test of HMF determination (n=6)

[0087] Prepare a 0.5wt% methanol solution of HMF, that is, weigh about 0.5g HMF, record the exact mass, dissolve it with methanol and make it up to volume in a 100ml volumetric flask, shake it well, make the sample solution to be tested, filter it through a 0.45μm filter membrane, and repeat the measurement 6 times on a machine (HPLC), and obtain the HMF content and the relative standard deviation (RSD) of HMF after conversion.

[0088]

[0089] It can be seen from the above table that the HMF content in the sample remains basically unchanged, and its RSD value is 0.0690%, which is less than 1%, indicating that the precision of HMF determination using this method is high.

[0090] 1.7 Spike recovery experiment

[0091] 1.7.1 OBMF sample spike recovery test (n = 3)

[0092] 1) Prepare 0.5 g / kg OBMF sample by adding 0.5 g of pure OBMF to 999.5 g of methanol, dissolve with ultrasonic aid, and cool to room temperature to prepare sample A;

[0093] 2) Take 100 g of sample A, add 0.05 g of pure OBMF, dissolve with ultrasonic aid, cool to room temperature to prepare sample B, take 5 g of sample B into a 10 ml volumetric flask, dissolve with methanol and dilute to the scale, and calculate the OBMF content in sample B after detection by HPLC, that is, the OBMF measurement value, OBMF recovery rate = (OBMF measurement value - OBMF content in sample) / OBMF spiked amount × 100%, repeat three times.

[0094] 3) Take 100 g of sample A, add 0.1 g of pure OBMF, dissolve with ultrasonic aid, cool to room temperature to prepare sample C, take 5 g of sample C into a 10 ml volumetric flask, dissolve with methanol and dilute to the scale line, and calculate the OBMF content in sample C after detection by machine (HPLC), that is, the OBMF measurement value, OBMF recovery rate = (OBMF measurement value - OBMF content in sample) / OBMF spiked amount × 100%, repeat three times.

[0095] 4) Take 100 g of sample A, add 0.2 g of pure OBMF, dissolve with ultrasonic aid, cool to room temperature to prepare sample D, take 5 g of sample D into a 10 ml volumetric flask, dissolve with methanol and dilute to the scale, and calculate the OBMF content in sample D after detection by HPLC, that is, the OBMF measurement value, OBMF recovery rate = (OBMF measurement value - OBMF content in sample) / OBMF spiked amount × 100%, repeat three times.

[0096]

[0097] It can be seen from the above table that in the OBMF recovery test, the relative standard deviation of OBMF is less than 1%; and the measured recovery rate is between 90% and 110%, proving that this method has high accuracy.

[0098] 1.7.2 HMF sample spike recovery test (n = 3)

[0099] 1) Prepare a 0.5 g / kg HMF sample by adding 0.5 g of pure HMF to 999.5 g of methanol, dissolve it with ultrasonic aid, and cool it to room temperature to prepare sample A;

[0100] 2) Take 100 g of sample A, add 0.05 g of pure HMF, dissolve with ultrasonic aid, cool to room temperature to prepare sample B, take 5 g of sample B into a 10 ml volumetric flask, dissolve with methanol and dilute to the scale, and calculate the HMF content in sample B after detection by machine (HPLC), that is, the HMF determination value, HMF recovery rate = (HMF determination value - HMF content in sample) / HMF spiked amount × 100%, repeat three times.

[0101] 3) Take 100 g of sample A, add 0.1 g of pure HMF, dissolve with ultrasonic aid, cool to room temperature to prepare sample C, take 5 g of sample C into a 10 ml volumetric flask, dissolve with methanol and dilute to the scale, and calculate the HMF content in sample C after detection by machine (HPLC), that is, the HMF determination value, HMF recovery rate = (HMF determination value - HMF content in sample) / HMF spiked amount × 100%, repeat three times.

[0102] 4) Take 100 g of sample A, add 0.2 g of pure HMF, dissolve with ultrasonic aid, cool to room temperature, prepare sample D, take 5 g of sample D into a 10 ml volumetric flask, dissolve with methanol and dilute to the scale, and calculate the HMF content in sample D after detection by machine (HPLC), that is, the HMF determination value, HMF recovery rate = (HMF determination value - HMF content in sample) / HMF spiked amount × 100%, repeat three times.

[0103]

[0104] It can be seen from the above table that in the HMF recovery test, the relative standard deviation of HMF is less than 1%; and the measured recovery rate is between 90% and 110%, which proves that this method has high accuracy.

[0105] 1.8 Determination of HMF and OBMF content in samples

[0106] According to the method in steps 1.3 and 1.4, weigh about 0.01 g of HMF crude product sample, record the accurate mass, dissolve it with methanol and make it up to 100 ml volumetric flask, dissolve it with ultrasonic aid, cool it to room temperature, prepare the sample solution to be tested, filter it through a 0.45 μm filter membrane, and measure it on an HPLC machine to obtain Figure 5 Spectrum of .

[0107] Substitute the obtained OBMF chromatographic peak area (peak area 619.21) and HMF chromatographic peak area (peak area 7504.02) into the OBMF standard curve equation and HMF standard curve equation in step 1.5, respectively, and obtain the HMF content of 0.1047 g / L and the OBMF content of 0.0093 g / L.

[0108] 1.9 Determination of OBMF content in samples

[0109] According to the method in steps 1.3 and 1.4, the HMF crude product samples at different storage temperatures were treated and subjected to high performance liquid chromatography, and the obtained chromatographic peak area was substituted into the OBMF standard curve equation in step 1.5 to obtain the OBMF content in the HMF crude product.

[0110] 2 Results Analysis

[0111] 2.1 Feasibility analysis of experimental methods

[0112] The OBMF in the sample was determined under the above chromatographic conditions. The chromatograms of the standard and sample are shown in Figure 3 and Figure 5 .

[0113] Figure 3 This is the HPLC spectrum of OBMF standard.

[0114] Figure 5 This is the HPLC spectrum of OBMF sample.

[0115] The retention time of OBMF under the above chromatographic conditions is 7.76min. By comparing the retention time of the standard and sample chromatograms, it can be confirmed that the sample is OBMF. By calculating the separation R>1.5, there is no interference from impurities, and the method is highly feasible.

[0116] 2.2 Analysis of experimental results on OBMF content in HMF crude products at different storage temperatures

[0117] Figure 6 This is a trend chart of OBMF content in HMF crude product at different storage temperatures.

[0118] Depend on Figure 6 It can be seen that under the same storage time, the OBMF content has an obvious upward trend with the increase of storage temperature; when the storage temperature is greater than 0℃, the OBMF content has an increasing trend with the passage of time, and this trend is closely related to the storage temperature. Specifically, when the corresponding storage temperature rises, the OBMF content increases; when the storage temperature is less than or equal to 0℃, the OBMF content does not change significantly with time and maintains a low content level. Therefore, 0℃ and below is a better storage temperature for HMF crude products.

[0119] Comparative Example 1

[0120] Weigh about 0.01 g of crude HMF sample, record the exact mass, dissolve it in methanol and adjust the volume to 100 ml in a volumetric flask, dissolve it with ultrasonic aid, cool it to room temperature, prepare the sample solution to be tested, filter it through a 0.45 μm filter membrane, and measure it on an HPLC machine. The chromatographic conditions are as follows:

[0121] Mobile phase: methanol: water = 5:95 mixture (volume ratio);

[0122] elution; isocratic elution;

[0123] Detection wavelength: 278nm;

[0124] Flow rate: 1.0 mL / min;

[0125] Injection volume: 10 μL;

[0126] Column temperature: 40°C;

[0127] The spectrum is obtained as Figure 7 As shown, the HMF peak (RT=8.366 min) was a cleaved peak and the OBMF peak was not separated.

[0128] Comparative Example 2

[0129] Weigh about 0.01 g of crude HMF sample, record the exact mass, dissolve it in methanol and adjust the volume to 100 ml in a volumetric flask, dissolve it with ultrasonic aid, cool it to room temperature, prepare the sample solution to be tested, filter it through a 0.45 μm filter membrane, and measure it on an HPLC machine. The chromatographic conditions are as follows:

[0130] Mobile phase: methanol

[0131] elution; isocratic elution;

[0132] Detection wavelength: 278nm;

[0133] Flow rate: 1.0 mL / min;

[0134] Injection volume: 10 μL;

[0135] Column temperature: 40°C;

[0136] The spectrum is obtained as Figure 8 As shown, the HMF peak (RT = 2.55 min) is interfered by other peaks, that is, the separation is insufficient.

[0137] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for simultaneously measuring the contents of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether, the method comprising: The crude 5-hydroxymethylfurfural product was sampled and methanol was used as solvent to prepare the sample solution to be tested; Under the following chromatographic conditions, the above-mentioned sample solution was subjected to high performance liquid chromatography analysis and determination, and the chromatographic peak areas of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether were recorded respectively; Substitute the chromatographic peak areas of the above 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether into the standard curve equations of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether, respectively, and calculate the contents of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether, The chromatographic conditions were as follows: Chromatographic column: C18 column; Mobile phase: methanol / water, gradient elution; Detection wavelength: 260~300nm.

2. The method according to claim 1, characterized in that: The C18 chromatographic column is Agilent ZORBAX Extend C18, 4.6 x 250 mm, 5 μm HPLC column, or other equivalent C18 column.

3. The method according to claim 1, characterized in that: The gradient elution is: Mobile phase: 0 min, methanol: water = 5:95; 10 min, methanol: water = 100:0; 15 min, methanol: water = 5:95, post-running time 2 min gradient elution, wherein the ratio of methanol to water is volume ratio.

4. The method according to claim 1, wherein When performing high performance liquid chromatography detection, the flow rate is 0.4 to 2 mL / min, the injection volume is 5 μL to 20 μL, and the column temperature is 25°C to 60°C.

5. The method according to claim 1, characterized in that: The chromatographic conditions are as follows: Chromatographic column: C18 column; Mobile phase: 0 min, methanol: water = 5:95; 10 min, methanol: water = 100:0; 15 min, methanol: water = 5:95, post-running time 2 min gradient elution, where the ratio of methanol to water is volume ratio; Detection wavelength: 278nm; Flow rate: 1.0 mL / min; Injection volume: 10 μL; Column temperature: 40℃.

6. The method according to claim 1, wherein When preparing the sample solution to be tested, weigh the crude 5-hydroxymethylfurfural, add methanol as a solvent, and adjust the volume to a 100 ml volumetric flask after ultrasonic dissolution, ultrasonic dissolution, cool to room temperature and keep for later use, wherein the ultrasonic dissolution time is 1 to 60 s, and the mass of the HMF crude product is weighed to be 5 mg to 25 mg.

7. The method according to claim 1, characterized in that: The standard curve equations of 5-hydroxymethylfurfural and bis-(5-formylfurfuryl) ether are obtained by the following method: accurately weighing 5-hydroxymethylfurfural standard and bis-(5-formylfurfuryl) ether standard respectively, using methanol as solvent, preparing a series of HMF standard solutions and OBMF standard solutions of different concentrations, performing high performance liquid chromatography under the same chromatographic conditions as mentioned above, and recording the peak areas respectively; drawing a standard curve with the peak area as the ordinate and the concentration of the standard solution as the abscissa to obtain a regression equation.

8. The method according to claim 5, characterized in that: The retention time of the 5-hydroxymethylfurfural is 4.9 min; the retention time of the bis-(5-formylfurfuryl) ether is 7.76 min.

9. The method according to claim 5, characterized in that: The standard curve equation of the 5-hydroxymethylfurfural is Y=71507.8513X+14.4614; the standard curve equation of the bis-(5-formylfurfuryl) ether is Y=67621.3542X-10.3899.

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