Preparation method and application of volatile aldehyde compound colorimetric detection card
By preparing a colorimetric detection card combining metal-organic framework materials and chemical indicators, the problems of expensive and complex detection equipment for volatile aldehydes have been solved, achieving portable, rapid, and sensitive detection results.
Patent Information
- Application Number
- CN202411089314.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-08
- Publication Date
- 2026-02-10
AI Technical Summary
Existing methods for detecting volatile aldehydes require expensive equipment and professional personnel, and are not suitable for rapid on-site monitoring.
A portable colorimetric detection card was prepared by combining metal-organic frameworks (MOFs) with chemical indicators. The rapid detection of volatile aldehydes was achieved by utilizing the porosity of MOFs and the reaction of indicators.
It achieves highly sensitive, low-cost, and easy-to-use detection of volatile aldehydes, making it suitable for on-site detection in various scenarios.
Smart Images
Figure CN121499475A_ABST
Abstract
Description
Technical Field
[0001] This application relates to a method for preparing a colorimetric detection card for volatile aldehyde compounds and its application, belonging to the field of rapid detection technology for volatile gases. Background Technology
[0002] Volatile aldehydes are widely present in the environment, primarily originating from industrial emissions, vehicle exhaust, and smoking. Long-term exposure poses potential health hazards, as they can irritate the eyes and respiratory tract, cause allergic reactions, and some aldehydes are even carcinogenic. Furthermore, volatile aldehydes are a significant pollutant in indoor air quality control, potentially impacting the health of residents. To reduce the environmental and human health impacts of volatile aldehydes, many countries and organizations have established relevant emission standards and control measures. Therefore, accurate monitoring of the emission process of these compounds is necessary to minimize harm to human health and the environment.
[0003] Common methods for detecting volatile aldehydes include gas chromatography, high-performance liquid chromatography, and mass spectrometry. These traditional methods rely on expensive equipment, require long operating times and highly trained personnel, and are not suitable for on-site monitoring. Summary of the Invention
[0004] To overcome these shortcomings, this application develops a portable detection device based on colorimetry for monitoring volatile aldehydes. By combining MOF frameworks and chemical indicators as sensing materials, it detects common volatile aldehydes in the environment.
[0005] The purpose of this invention is to provide a rapid and sensitive colorimetric detection card for testing volatile aldehyde compounds. The developed detection card has the advantages of high sensitivity, low cost and ease of use, making it very suitable for application in a variety of scenarios.
[0006] To this end, the present invention first prepares a metal-organic framework (MOF) material, and then adds various indicators to the MOFs to construct an encapsulated composite material. The composite material is then mixed with ethanol to form a uniform suspension droplet, which is then deposited onto a supporting substrate to develop a colorimetric detection card for volatile aldehyde compounds.
[0007] According to one aspect of this application, a method for preparing a colorimetric detection card for volatile aldehyde compounds, the method comprising at least the following steps:
[0008] Step I: Mix ZrCl4, formic acid and water, and 1,3,5-benzenetricarboxylic acid to form a mixture, and obtain MOF material;
[0009] Step II: Mix the MOFs material obtained in Step I with ethanol to form Suspension I, add an indicator, stir, and obtain the encapsulated composite material;
[0010] Step III: Mix the composite material obtained in Step II with ethanol to form Suspension II, and apply it to the substrate to obtain a colorimetric detection card for volatile aldehyde compounds.
[0011] Optionally, in step I, the molar ratio of ZrCl4 to 1,3,5-benzenetricarboxylic acid in the mixture is 1:1 to 3:2.
[0012] Optionally, in the mixture of formic acid and water, the volume ratio of formic acid to H2O is 1:1 to 1:6.
[0013] Optionally, in step II, the concentration of suspension I is 5–20 mg / mL.
[0014] Optionally, the indicator includes at least one of 2,4-dinitrophenylhydrazine, phenolic reagent, and pararosaniline.
[0015] Optionally, the indicator is a mixed indicator comprising a phenol reagent and indicator A, wherein the mass ratio of the phenol reagent and indicator A is 1:1.
[0016] Optionally, when the phenol reagent is phenol red, the indicator A is pararosaniline;
[0017] When the phenolic reagent is thymol blue, the indicator A is selected from hydroxylamine hydrochloride and pararosaniline.
[0018] Optionally, the stirring time is 6 to 24 hours.
[0019] Optionally, the concentration of the indicator is 10–30 mg / mL.
[0020] Optionally, in step III, the concentration of suspension II is 5–20 mg / mL.
[0021] Optionally, the substrate is selected from at least one of polyvinylidene fluoride membrane, filter paper, and wax printing paper.
[0022] According to another aspect of this application, an application of a colorimetric detection card for volatile aldehydes is provided, wherein the colorimetric detection card is placed in a detection device and reacts with volatile aldehydes.
[0023] Optionally, the volatile aldehyde compound is selected from at least one of formaldehyde, acetaldehyde, and propionaldehyde.
[0024] Optionally, the concentration of the volatile aldehyde compound is 1.0 to 50 ppm.
[0025] Optionally, the contact reaction time is 10 to 20 minutes.
[0026] The beneficial effects that this application can produce include:
[0027] 1) The colorimetric detection card of the present invention utilizes the porosity of MOFs materials as an ideal framework to encapsulate guest molecules. This host-guest system can effectively restrict the movement of guest molecules, reduce quenching caused by guest aggregation, and effectively improve the stability of the sensing material.
[0028] 2) Powdered MOFs have poor processability. Dropping them onto a polyvinylidene fluoride (PVDF) membrane substrate allows for the fabrication of a portable colorimetric detection device. This colorimetric detection card is simple to prepare, easy to operate, and suitable for on-site detection. It provides clear detection results with only a short contact time with the target analyte.
[0029] In summary, the simple and efficient preparation of this material has significant scientific and practical value. Attached Figure Description
[0030] Figure 1 Color comparison of the colorimetric detection card prepared in this application before and after exposure to formaldehyde environment; a) before exposure to formaldehyde environment; b) after exposure to formaldehyde environment; (position 1: MOFs@2,4-dinitrophenylhydrazine, position 2: MOFs@phenol reagent, position 3: MOFs@pararosaniline, position 4: MOFs@phenol red, position 5: MOFs@hydroxylamine hydrochloride / thymol blue, position 6: MOFs@pararosaniline / thymol blue, position 7: MOFs@pararosaniline / phenol red);
[0031] Figure 2 The XRD patterns of MOFs before and after encapsulation of the indicator in Example 5 of this application are shown. Detailed Implementation
[0032] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.
[0033] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.
[0034] The preparation examples and analytical methods in this application are as follows:
[0035] The MOF materials before and after encapsulation with the indicator were tested using X-ray diffraction.
[0036] According to one embodiment of this application, a method for constructing MOF materials is provided:
[0037] A certain amount of zirconium chloride (ZrCl4) was added to a mixture of formic acid / H2O at a certain volume ratio, and then a certain amount of 1,3,5-benzenetricarboxylic acid was added to the solution. The mixture was then stirred at room temperature for 24 hours. After the solution turned milky white, the sample was collected by centrifugation, and then washed repeatedly with a methanol / H2O mixture. After centrifugation, the sample was heated in a vacuum oven at 60°C for 12 hours to obtain a white MOF sample.
[0038] The molar ratio of ZrCl4 to 1,3,5-benzenetricarboxylic acid is 3:1, with ZrCl4 having a molar amount of 1.0 mmol. The volume ratio of formic acid / H2O mixture is 1:1 to 1:6, and the volume of the mixed solution is 20 mL.
[0039] According to one embodiment of this application, a method for constructing MOFs@indicator materials is disclosed.
[0040] The obtained MOFs materials were dispersed in ethanol, with a concentration of 5-20 mg / mL. 10-30 mg of indicator (the ratio of the two indicators in the mixed indicator was 1:1) was added to the mixed solution. After magnetic stirring for 6-24 hours, the sample was obtained by centrifugation. The sample was then repeatedly washed and centrifuged with ethanol solution to obtain the encapsulated composite material.
[0041] According to one embodiment of this application, the supporting substrate used is a polyvinylidene fluoride membrane. A certain amount of an ethanol suspension of the composite material (5-20 mg / mL) is drop-coated onto the substrate, and after drying, a colorimetric detection card for volatile aldehyde compounds is obtained.
[0042] According to another aspect of this application, after the prepared colorimetric test card reacts with formaldehyde gas at room temperature for 10 minutes, the color of the colorimetric test card deepens.
[0043] Preparation Example 1: Preparation of Metal-Organic Frameworks (MOFs) Materials
[0044] 1.0 mmol of zirconium chloride (ZrCl4) was added to a 1:1 mixture of formic acid and H2O (total volume 20 mL), followed by 0.33 mmol of 1,3,5-benzenetricarboxylic acid. The mixture was then stirred at room temperature for 24 hours. After the solution turned milky white, the sample was collected by centrifugation, washed repeatedly with a methanol / H2O mixture, centrifuged again, and then heated in a vacuum oven at 60 °C for 12 hours to obtain a white MOF sample.
[0045] Preparation Example 2: Preparation of Metal-Organic Frameworks (MOFs) Materials
[0046] 1.0 mmol of zirconium chloride (ZrCl4) was added to a mixture of formic acid / H2O (total volume 20 mL) at a volume ratio of 1:2. Then, 0.33 mmol of 1,3,5-benzenetricarboxylic acid was added to the solution, and the mixture was stirred at room temperature for 24 hours. After the solution turned milky white, the sample was collected by centrifugation, washed repeatedly with a methanol / H2O mixture, centrifuged again, and then heated in a vacuum oven at 60 °C for 12 hours to obtain a white MOF sample.
[0047] Preparation Example 3: Preparation of Metal-Organic Frameworks (MOFs) Materials
[0048] 1.0 mmol of zirconium chloride (ZrCl4) was added to a mixture of formic acid / H2O (total volume 20 mL) at a volume ratio of 1:4. Then, 0.33 mmol of 1,3,5-benzenetricarboxylic acid was added to the solution, and the mixture was stirred at room temperature for 24 hours. After the solution turned milky white, the sample was collected by centrifugation, washed repeatedly with a methanol / H2O mixture, centrifuged again, and then heated in a vacuum oven at 60 °C for 12 hours to obtain a white MOF sample.
[0049] Preparation Example 4: Preparation of Metal-Organic Frameworks (MOFs) Materials
[0050] 1.0 mmol of zirconium chloride (ZrCl4) was added to a mixture of formic acid / H2O (total volume 20 mL) at a volume ratio of 1:5. Then, 0.33 mmol of 1,3,5-benzenetricarboxylic acid was added to the solution, and the mixture was stirred at room temperature for 24 hours. After the solution turned milky white, the sample was collected by centrifugation, washed repeatedly with a methanol / H2O mixture, centrifuged again, and then heated in a vacuum oven at 60 °C for 12 hours to obtain a white MOF sample.
[0051] Preparation Example 5: Preparation of Metal-Organic Frameworks (MOFs) Materials
[0052] 1.0 mmol of zirconium chloride (ZrCl4) was added to a mixture of formic acid / H2O (total volume 20 mL) at a volume ratio of 1:6. Then, 0.33 mmol of 1,3,5-benzenetricarboxylic acid was added to the solution, and the mixture was stirred at room temperature for 24 hours. After the solution turned milky white, the sample was collected by centrifugation, washed repeatedly with a methanol / H2O mixture, centrifuged again, and then heated in a vacuum oven at 60 °C for 12 hours to obtain a white MOF sample. Figure 2 This indicates that the prepared MOFs material has good phase purity.
[0053] Example 1: Preparation of MOFs@Indicator Composite Material
[0054] The MOFs material obtained in Preparation Example 5 was dispersed in ethanol with a concentration of 5 mg / mL. 10 mg of 2,4-dinitrophenylhydrazine indicator was added to the mixed solution. After stirring magnetically for 6 hours, the sample was obtained by centrifugation. The encapsulated composite material was obtained by repeatedly washing and centrifuging with ethanol solution.
[0055] Example 2: Preparation of MOFs@Indicator Composite Material
[0056] The MOFs material obtained in Preparation Example 5 was dispersed in ethanol with a concentration of 5 mg / mL. 20 mg of phenol reagent indicator was added to the mixed solution. After stirring magnetically for 6 hours, the sample was obtained by centrifugation. The encapsulated composite material was obtained by repeatedly washing and centrifuging with ethanol solution.
[0057] Example 3: Preparation of MOFs@Indicator Composite Material
[0058] The MOFs material obtained in Preparation Example 5 was dispersed in ethanol with a concentration of 5 mg / mL. 30 mg of pararosaniline indicator was added to the mixed solution. After stirring magnetically for 6 hours, the sample was obtained by centrifugation. The encapsulated composite material was obtained by repeatedly washing and centrifuging with ethanol solution.
[0059] Example 4: Preparation of MOFs@Indicator Composite Material
[0060] The MOFs material obtained in Preparation Example 5 was dispersed in ethanol with a concentration of 10 mg / mL. 20 mg of phenol red indicator was added to the mixed solution. After stirring magnetically for 6 hours, the sample was obtained by centrifugation. The encapsulated composite material was obtained by repeatedly washing and centrifuging with ethanol solution.
[0061] Example 5: Preparation of MOFs@Indicator Composite Material
[0062] The MOFs material obtained in Preparation Example 5 was dispersed in ethanol, and the concentration of the MOFs ethanol suspension was 20 mg / mL. 20 mg of mixed indicator (the mass ratio of hydroxylamine hydrochloride indicator to thymol blue indicator in the mixed indicator was 1:1) was added to the mixed solution. After stirring magnetically for 6 hours, the sample was obtained by centrifugation. After repeated washing and centrifugation with ethanol solution, the encapsulated composite material was obtained.
[0063] Example 6: Preparation of MOFs@Indicator Composite Material
[0064] The MOFs material obtained in Preparation Example 5 was dispersed in ethanol, and the concentration of the MOFs ethanol suspension was 10 mg / mL. 20 mg of mixed indicator (the mass ratio of pararosaniline indicator to thymol blue indicator in the mixed indicator was 1:1) was added to the mixed solution. After magnetic stirring for 12 hours, the sample was obtained by centrifugation. After repeated washing and centrifugation with ethanol solution, the encapsulated composite material was obtained.
[0065] Example 7: Preparation of MOFs@Indicator Composite Material
[0066] The MOFs material obtained in Preparation Example 5 was dispersed in ethanol, with a MOFs ethanol suspension concentration of 10 mg / mL. 20 mg of a mixed indicator (the mass ratio of pararosaniline indicator to phenol red indicator in the mixed indicator was 1:1) was added to the mixed solution. After magnetic stirring for 24 hours, the sample was obtained by centrifugation. The sample was then repeatedly washed with ethanol solution and centrifuged again to obtain the encapsulated composite material. Figure 2 It can be seen that the XRD patterns of MOFs materials before and after encapsulation are almost unchanged, indicating that the encapsulation of the indicator has no effect on the framework structure of MOFs.
[0067] Example 8: Preparation of a colorimetric detection card for volatile aldehyde compounds
[0068] The MOFs@indicator material prepared in Example 7 was mixed with an ethanol solution to form a uniform suspension with a concentration of 5 mg / mL. Using a polyvinylidene fluoride membrane as a supporting substrate, a certain amount of the suspension was drop-coated onto the substrate, and after drying, a colorimetric detection card for volatile aldehyde compounds was obtained.
[0069] Example 9: Preparation of a colorimetric detection card for volatile aldehyde compounds
[0070] The MOFs@indicator material prepared in Example 7 was mixed with an ethanol solution to form a uniform suspension with a concentration of 10 mg / mL. Using a polyvinylidene fluoride membrane as a supporting substrate, a certain amount of the suspension was drop-coated onto the substrate, and after drying, a colorimetric detection card for volatile aldehyde compounds was obtained.
[0071] Example 10: Preparation of a colorimetric detection card for volatile aldehyde compounds
[0072] The MOFs@indicator material prepared in Example 7 was mixed with an ethanol solution to form a uniform suspension with a concentration of 20 mg / mL. Using a polyvinylidene fluoride membrane as a supporting substrate, a certain amount of the suspension was drop-coated onto the substrate, and after drying, a colorimetric detection card for volatile aldehyde compounds was obtained.
[0073] Example 11
[0074] The colorimetric detection card prepared in Example 9 was placed in the designed detection device for detection. When exposed to a trace amount of formaldehyde gas (formaldehyde concentration of 1.0 ppm), after a reaction of 10 minutes, the formaldehyde concentration was measured. Figure 1 As can be seen, the colorimetric test card shows obvious color changes.
[0075] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.
Claims
1. A method for preparing a colorimetric detection card for volatile aldehyde compounds, characterized in that, The method includes at least the following steps: Step I: Mix ZrCl4, formic acid and water, and 1,3,5-benzenetricarboxylic acid to form a mixture, and obtain MOF material; Step II: Mix the MOFs material obtained in Step I with ethanol to form Suspension I, add an indicator, stir, and obtain the encapsulated composite material; Step III: Mix the composite material obtained in Step II with ethanol to form Suspension II, and apply it to the substrate to obtain a colorimetric detection card for volatile aldehyde compounds.
2. The preparation method according to claim 1, characterized in that, In step I, In the mixture, the molar ratio of ZrCl4 to 1,3,5-benzenetricarboxylic acid is 1:1 to 3:
2.
3. The preparation method according to claim 1, characterized in that, In a mixture of formic acid and water, the volume ratio of formic acid to H2O is 1:1 to 1:
6.
4. The preparation method according to claim 1, characterized in that, In step II, the concentration of suspension I is 5–20 mg / mL; Preferably, the indicator comprises at least one of 2,4-dinitrophenylhydrazine, phenolic reagent, and pararosaniline; Preferably, the indicator is a mixed indicator comprising a phenol reagent and indicator A, wherein the mass ratio of the phenol reagent and indicator A is 1:1; Preferably, when the phenol reagent is phenol red, the indicator A is pararosaniline; When the phenolic reagent is thymol blue, the indicator A is selected from hydroxylamine hydrochloride and pararosaniline. Preferably, the stirring time is 6 to 24 hours.
5. The preparation method according to claim 4, characterized in that, In step II, The concentration of the indicator is 10–30 mg / mL.
6. The preparation method according to claim 1, characterized in that, In step III, the concentration of suspension II is 5–20 mg / mL; Preferably, the substrate is selected from at least one of polyvinylidene fluoride membrane, filter paper, and wax printing paper.
7. An application of a colorimetric detection card for volatile aldehyde compounds, characterized in that, Place the colorimetric test card in the detection device and allow it to react with volatile aldehyde compounds; The colorimetric test card is prepared by the preparation method of any one of claims 1 to 6.
8. The application according to claim 7, characterized in that, The volatile aldehydes are selected from at least one of formaldehyde, acetaldehyde, and propionaldehyde.
9. The application according to claim 7, characterized in that, The concentration of the volatile aldehyde compounds is 1.0 to 50 ppm.
10. The application according to claim 7, characterized in that, The contact reaction time is 10 to 20 minutes.