A method for rapid detection of redox active compounds in air

Abstract

The invention discloses a method for rapidly detecting redox active compounds in the air, which combines the color development reaction of gold nanoparticles, the redox characteristics of the redox active compounds in the air and the photochemical reaction, selects benzoquinone as a standard, reduces chloroauric acid in situ on the surface of the filter membrane under light to obtain colored gold nanoparticles, extracts the RGB color intensity value of the filter membrane through the smart phone software Color Swatch, uses the color average value of the G component to establish the quantitative relationship between the effective absorbance of the filter membrane and the benzoquinone concentration, draws a standard curve of the benzoquinone concentration, and thus realizes the measurement of the concentration of the redox active compounds in the air. The detection method provided by the invention is simple to operate, does not require large instruments, omits complex processes such as sample extraction, has rapid detection, intuitive results, low cost, and a detection limit of up to 0.026 μg·mm ‑2 , which can realize in situ rapid detection on the filter membrane.

Description

Technical Field

[0001] The invention relates to the fields of optical technology and environmental monitoring, and in particular to a method for rapidly detecting redox active compounds in the air. Background Art

[0002] At present, studies have found that atmospheric particulate matter has many adverse effects on human health, atmospheric environment and global climate change. Among them, redox-active compounds in the air are considered to be the main cause of human lung cancer, cardiovascular diseases and other diseases. These compounds have high oxidation potential and can be activated into electrophilic active metabolites, which in turn induce the production of reactive oxygen species (ROS) in cells, leading to oxidative stress and airway inflammation. Therefore, the quantitative and qualitative analysis of redox-active compounds in the air is very important for evaluating the impact on air quality, ecological health and global climate. Among them, quinones and transition metals are considered to be one of the main components of this type of redox-active compounds.

[0003] In the related art, the commonly used methods for quantitative detection of redox-active compounds in the air are mainly dithiothreitol method (DTT) and total organic carbon method. The DTT method is a method based on the reduction capacity of DTT, according to which the consumption rate of DTT is proportional to the amount of redox-active compounds to quantify the amount of active compounds in the air. Such redox-active compounds catalyze DTT to reduce oxygen to superoxide compounds. Another commonly used total organic carbon method is based on the conversion of particulate matter into carbon dioxide to measure the concentration of carbon. Such methods can only determine the carbon content of redox-active compounds in the atmosphere. Due to the differences in the source and region of particulate matter, the conversion coefficient of organic carbon and organic particulate matter cannot be determined, and the acidification pretreatment easily leads to the loss of some organic matter due to low solubility under acidic conditions; in addition, the total organic carbon method cannot measure the inorganic components of redox-active compounds in the air, such as some transition metals. However, both widely used detection methods require the extraction of air particles and dissolution in water or organic solvents before analyzing the particles. Therefore, the development of a method for rapid in-situ detection directly on the filter membrane without extracting particles is of great significance to human health and safety and air quality assessment.

[0004] After searching domestic and foreign patents and literature, we only found that smartphones were used to detect pH test strips, NO2 in the air, urine, etc., such as Li H et al. Analytical Chemistry, 93 (46), 15452-15458; Cerrato-Alvarez, Metal. Sensors and Actuators B: Chemical, 338, 129867; Publication No. CN109752374A. No related reports have been found on the quantitative detection of redox active compounds in the air based on smartphones using the reducibility of redox active compounds in the air, the color development characteristics of gold nanoparticles and photochemical reactions. Summary of the invention

[0005] The purpose of the present invention is to provide a fast and simple method for detecting redox active compounds in the air, so as to overcome the defects of the existing detection methods that are complicated and require professional detection personnel to operate, avoid the cumbersome particle extraction process, and realize the in-situ detection of redox active compounds in the air on the filter membrane.

[0006] In order to achieve the above object, the present invention is implemented by the following technical methods:

[0007] A method for rapidly detecting redox-active compounds in the air, in which gold nanoparticles are obtained by in-situ reduction on the surface of a filter membrane under light, and redox-active compounds in the air are detected using a smart phone based on the color development reaction and photochemical reaction of the gold nanoparticles.

[0008] Preferably, the method for rapid detection of redox active compounds in air of the present invention is characterized by comprising the following steps:

[0009] (1) Collection of standard samples and real air samples

[0010] Benzoquinone was selected as the standard sample of redox-active compounds in the air. The prepared standard solution of benzoquinone was first passed through a dust generating device to obtain benzoquinone particles, which were then collected on a filter membrane for different periods of time to obtain benzoquinone particles of different masses. The PM10 sample was collected on the filter membrane through a flow air sampler.

[0011] (2) Establishment of standard curve of air redox active compounds based on smartphone

[0012] First, collect standard samples of different concentrations, cut a certain circular area, spray 12.75mM chloroauric acid solution on the filter membrane by spraying, and place it under light. The distance between the membrane and the xenon lamp is 5cm. After a certain period of light exposure, the color of the filter membrane changes from brown to pink purple;

[0013] The color-developed filter membrane is placed in a sealed, light-proof box made of stainless steel. The bottom of the box can be pulled out and inserted to place the sample. A small light bulb is placed on the side to maintain a fixed light intensity. There is an opening on the top of the box that is the same size as the mobile phone camera, which is used to align the mobile phone camera. The center position of the filter membrane and the center point of the camera hole are in the same vertical direction so that the camera of the smartphone can fully capture the bottom through the top opening to collect the RGB color intensity of the filter membrane;

[0014] Place the phone at the opening of the box and open the Color Swatch software; read the RGB color intensity value of the filter;

[0015] Select the color average of the G component and define the effective absorbance EA G As the dependent variable, establish EA G The quantitative relationship between the concentration of isoquinone and the concentration of isoquinone is plotted as the independent variable. G is the standard curve of the dependent variable;

[0016] (3) Substitute the G value obtained from the collected PM10 air sample according to steps (1) and (2) into the above standard curve, and the redox-active compounds in the real sample can be calculated based on the air flow rate and sampling area.

[0017] Preferably, the gold nanoparticles of the present invention are gold nanoparticles that are colored by in-situ reduction of chloroauric acid by redox-active compounds on the surface of the filter membrane under light.

[0018] Preferably, the filter membrane of the present invention is a glass fiber membrane, and the filter membrane area ranges from 78.5 to 15394 mm 2 .

[0019] Preferably, the present invention uses a 100 ppm concentration of benzoquinone solution, the collection time is 5-180 min, and the mass on the filter membrane is measured by the total organic carbon method. The specific process of the total organic carbon method is: first extract the benzoquinone particles on the filter membrane in deionized water and then measure the water-soluble organic carbon on the filter membrane to obtain the benzoquinone concentration per unit area of ​​the filter membrane.

[0020] Preferably, the real PM10 sample collection of the present invention requires that the filter membrane be baked at 450°C for 12 hours, cooled to room temperature and dried, and then collected on the filter membrane through a flow air sampler at a sampling flow rate of 500L / min. After the sample collection is completed, it is sealed with aluminum foil and stored in a -20°C refrigerator for later use.

[0021] Preferably, the cross-sectional area of ​​the standard sample of the present invention is 78.5-1962mm 2 , 12.75mM chloroauric acid solution was sprayed on the filter membrane by spraying, with a spraying mass of 0.12-0.3g.

[0022] Preferably, the present invention uses a xenon lamp to excite the photochemical reaction, and the illumination time is 10-30min.

[0023] Preferably, the flashlight is turned off when the mobile phone of the present invention reads the RGB color intensity, and the linear concentration range of the obtained benzoquinone particles is 0.026-0.49 μg / mm 2 , E.A. G The linear relationship with benzoquinone concentration is EA G =0.1897x+0.0013,R 2 =0.973.

[0024] Compared with the prior art, the present invention has the following advantages and effects:

[0025] 1. The present invention provides a method for quickly detecting redox-active compounds in the air based on smartphone colorimetry, which combines the redox properties of redox-active compounds in the air, the color development reaction of gold nanoparticles, and the photochemical reaction characteristics and is applied to atmospheric environment detection.

[0026] 2. The present invention provides a method for rapidly detecting redox-active compounds in the air based on a smartphone colorimetric method. The method does not require complicated extraction steps and can directly reduce gold nanoparticles in situ on the filter membrane surface to achieve rapid and efficient detection of redox-active compounds. The method has a short reaction time, a simple system, and a wide range of applications.

[0027] 3. The present invention provides a method for quickly detecting redox-active compounds in the air based on smartphone colorimetry, which uses a mobile phone App to perform image acquisition and color analysis, so that the colorimetric detection results are accurate, fast, easy to read, and can achieve rapid detection of redox-active compounds in particulate matter without the need for additional equipment and complex testing.

[0028] 4. The present invention applies the photochemical reaction and color development reaction of gold nanoparticles to the detection of atmospheric particulate matter, and develops a new application of smartphones in the field of air sensors for the detection of redox-active compounds in the air.

[0029] 5. The method for rapid detection of redox-active compounds in the air based on smartphone colorimetry established by the present invention can be applied to the detection of redox-active compounds in PM10 under different environments, and has great application value and marketability for remote areas with a lack of analytical equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a working principle diagram of the rapid detection of redox active compounds in the air of the present invention.

[0031] Figure 2 The invention relates to a dust generating device for the benzoquinone particles.

[0032] Figure 3 is the mass of benzoquinone per unit area of ​​the filter membrane at different deposition times.

[0033] Figure 4 It is the scanning electric mobility particle size spectrometer of the present invention.

[0034] Figure 5 1 is a particle size distribution diagram of benzoquinone of the present invention.

[0035] Figure 6 This is the XRD characterization of the gold nanoparticles@glass fiber filter membrane of the present invention.

[0036] Figure 7 The RGB color intensity changes of the gold nanoparticles@glass fiber filter membrane at different concentrations of the present invention.

[0037] Figure 8 EA of the present invention G Standard curve with different concentrations of benzoquinone particles.

[0038] Fig. 9 This is a comparison chart of redox active compounds and PM10 concentrations in the Bern region of Switzerland in December according to the present invention.

[0039] Fig.10 This is a comparison chart of redox active compounds and PM10 concentrations in the Rigi mountain region of Switzerland in December of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in combination with specific implementation methods and examples. The specific embodiments described here are only used to explain the present invention and are not used to limit the invention.

[0041] A method for rapidly detecting redox active compounds in air comprises the following steps:

[0042] 1. Collection of standard samples and real air samples

[0043] The present invention selects benzoquinone as a standard sample of redox-active compounds in the air, selects a benzoquinone solution with a concentration of 100 ppm as a dust-generating solution, and collects the generated benzoquinone particles on a glass fiber membrane through a dust-generating device. The collection time is 5-180 minutes. The mass on the filter membrane is measured by a total organic carbon method. The specific process is to first extract the benzoquinone particles on the filter membrane in deionized water and then measure the water-soluble organic carbon on the filter membrane to obtain the benzoquinone concentration per unit area of ​​the filter membrane.

[0044] The specific process of collecting PM10 air samples is to bake the filter membrane at 450℃ for 12h, cool it to room temperature and dry it, and then collect it on the filter membrane through a flow air sampler with a sampling flow rate of 500L / min. After the sample is collected, it is sealed with aluminum foil and stored in a -20℃ refrigerator for later use.

[0045] 2. Establishment of standard curve of air redox active compounds based on smartphone

[0046] (1) First, collect standard samples of different concentrations, cut a certain circular area, and then spray 12.75mM chloroauric acid solution on the filter membrane by spraying. Place it under light with the distance between the membrane and the xenon lamp being 5cm. After a certain period of light exposure, the color of the filter membrane changes from brown to pink purple.

[0047] (2) The color-developed filter membrane is placed in a sealed, light-proof box made of stainless steel. The bottom of the box can be pulled out and inserted to place the sample. A small light bulb is placed on the side to maintain a fixed light intensity. An opening of the same size as the mobile phone camera is set at the top of the box for aligning the mobile phone camera. The center position of the filter membrane and the center point of the camera hole are in the same vertical direction so that the camera of the smartphone can fully capture the bottom through the top opening to collect the RGB color intensity of the filter membrane.

[0048] Place the smartphone at the opening of the box, turn off the flash, and open the Color Swatch software to read the RGB color intensity value of the filter.

[0049] (3) Preparation of blank filter membrane sample: The filter membrane without benzoquinone particles is colored in the same manner as steps (1) and (2) to obtain the RGB color value of the blank filter membrane sample.

[0050] (4) Select the color average of the G component and define the effective absorbance EA G is the dependent variable, EA G The formula is as follows,

[0051]

[0052] Among them G b -Color intensity value of G component in the filter sample, G s -Color intensity value of G component in blank filter sample,

[0053] Building an EA G The quantitative relationship between the concentration of isoquinone and the concentration of isoquinone is plotted as the independent variable. G is the standard curve of the dependent variable.

[0054] 3. Detection of air redox active compounds

[0055] Cut off the same area of ​​the collected PM10 air sample as the standard sample, and substitute the G value obtained in steps (1) and (2) into the above standard curve in step (4). The concentration of redox-active compounds in the real sample can be calculated based on the air flow rate and sampling area.

[0056] The present invention utilizes the reducibility of redox active compounds in the air, the color development characteristics of gold nanoparticles and photochemical reactions to quantitatively detect redox active compounds in the air based on smartphones. Combining the reducibility of particulate matter, the color development reaction of gold nanoparticles with a portable and popular smartphone mobile terminal device, the establishment of a new method for rapid, convenient and sensitive in-situ detection of redox active compounds in the air is of great significance for evaluating human health and air quality.

[0057] The detection method of the present invention is described in detail below with reference to the accompanying drawings:

[0058] 1. Instruments and Reagents

[0059] All chemical reagents were purchased from commercial sources and used directly without further purification. The dust generating device consisted of an atomizer, a diffusion dryer, a high efficiency filter and a fixture.

[0060] 2. Collection and Characterization of Standard Samples

[0061] like Figure 1 As shown in the figure, under light conditions, benzoquinone molecules can undergo redox reactions with chloroauric acid solution to generate colored gold nanoparticles. At the same time, benzoquinone molecules are also one of the components of redox-active compounds in the air, and the benzoquinone molecule has a simple structure, so we chose benzoquinone as the standard sample and collected it on the filter membrane. Under the action of light, a color reaction occurred, and the brown membrane surface was in situ reduced to obtain pink gold nanoparticles. Using the principle of color reaction under light, we use Figure 2 The device shown is equipped with a 100ppm benzoquinone solution. High-speed compressed air is first filtered through a high-efficiency filter and then passed through an atomizer containing the benzoquinone solution. The atomizer generates polydispersed benzoquinone particles that enter the diffusion dryer. Since the diffusion dryer is filled with silica gel particles, when the particles are emitted from the atomizer and enter the diffusion dryer, the moisture on their surface will be adsorbed by the silica gel particles to obtain dry particles. The dried benzoquinone particles are collected on the glass fiber membrane. The collection time is 5-180 minutes, and the corresponding benzoquinone particle mass per unit area on the filter membrane is 0.026-0.49μg / mm 2 , corresponding to Figure 3 We used a scanning mobility particle sizer (SMPS) to perform particle size scanning analysis ( Figure 4), SMPS is composed of a differential mobility analyzer (Differential Mobility Analyzer, referred to as DMA) and a condensation particle counter (Condensation Particle Counters, referred to as CPC). DMA is used to screen out monodisperse particles with different mobility diameters, and CPC is used to detect the number concentration of the screened particle size. The particle size of the benzoquinone particles obtained by the dust generation device is mostly concentrated around 65nm ( Figure 5 ).

[0062] 3. Establishing a standard curve for air redox-active compounds based on a smartphone

[0063] (1) Ten standard samples of different concentrations were collected, and a circular area with a diameter of 20 mm was cut. Then, a 12.75 mM 0.12 g chloroauric acid solution was sprayed on the filter membrane by spraying. The membrane was placed under light, and the distance between the membrane and the xenon lamp was 5 cm. After 20 minutes of light exposure, the color of the filter membrane changed from brown to pink purple. X-ray diffractometer can prove that the gold nanoparticles formed by in-situ reduction on the surface of the filter membrane are polycrystalline ( Figure 6 ).

[0064] (2) The color-developed filter membrane is placed in a sealed, light-proof box made of stainless steel. The bottom of the box can be pulled out and inserted to place the sample. A small light bulb is placed on the side to maintain a fixed light intensity. An opening of the same size as the mobile phone camera is set at the top of the box for aligning the mobile phone camera. The center position of the filter membrane and the center point of the camera hole are in the same vertical direction so that the camera of the smartphone can fully capture the bottom through the top opening to collect the RGB color intensity of the filter membrane.

[0065] Place the smartphone in the opening of the box, turn off the flash, and open the Color Swatch software. Read the RGB color intensity value of the filter. We see that the color of the image is complementary to the color absorbed. The pink-purple filter absorbs green light and reflects red and blue light. And from Figure 7 It can be seen that the intensity of green G, which is complementary to red, decreases more significantly. Therefore, we choose the G component as the next dependent variable. Substituting the G values ​​at different concentrations into the effective absorbance formula, we get EA G . Create an EA G The linear relationship with the concentration of benzoquinone is shown in the working curve. Figure 8 shown.

[0066] The concentration of benzoquinone particles ranged from 0.026-0.49 μg / mm 2 With EA G The color intensity is linearly related as follows:EA G=0.1897x+0.0013R 2 = 0.973, where EAG is the effective absorbance of the membrane sample, and x is the equivalent benzoquinone concentration of the membrane sample.

[0067] The detection limit is defined as the lowest concentration of the sample tested, that is, the color response or absorption peak intensity of the lowest concentration sample is greater than three times the standard deviation (SD) of the blank sample measurement, that is, the signal-to-noise ratio (S / N) is greater than 3;

[0068] S / N=(average sample -average blank ) / SD blank

[0069] Among them, average sample 、average blank , SD blank They represent the average absorption peak intensity of the real sample, the average absorption peak intensity of the blank sample, and the standard deviation of the absorption peak intensity of the blank sample respectively.

[0070] According to the above formula, the detection limit is 0.026 μg / mm 2 .

[0071] Embodiment 1:

[0072] PM10 filter membrane samples in Bern, Switzerland (collection point is located at a traffic intersection) were collected every other day from December 1, 2020 to December 31, 2020. See Table 1 for details. After cutting a circular area with a diameter of 20 mm from the filter membrane, 12.75 mM 0.12 g chloroauric acid solution was sprayed on the filter membrane by spraying, and placed under light. The distance between the membrane and the xenon lamp was 5 cm. After 20 minutes of illumination, the color of the filter membrane changed from brown to pink purple. The color-developed filter membrane was placed in a closed and opaque box made of stainless steel. The bottom of the box can be pulled out and inserted to place the sample. A small light bulb is placed on the side to maintain a fixed light intensity. An opening of the same size as the mobile phone camera is set at the top of the box for aligning the mobile phone camera. The center position of the filter membrane and the center point of the camera hole are in the same vertical direction so that the camera of the smartphone can fully capture the bottom through the top opening to collect the RGB color intensity of the filter membrane.

[0073] Place the iPhone 13 at the opening of the box, turn off the flash, and open the Color Swatch software. Read the RGB color intensity value of the filter membrane. Substitute the G value at different concentrations into the effective absorbance formula to obtain EA GThe concentration of redox active compounds in the real sample can be calculated based on the standard curve, air flow rate and sampling area. The concentration of redox active compounds in the air in December in Bern, Switzerland can be found in Fig. 9 .Depend on Fig. 9 It can be seen that the concentration of redox active compounds in the Bern area ranges from 3.63 to 9.81 μg·m -3 And it is basically consistent with the changing trend of PM10.

[0074] Embodiment 2:

[0075] PM10 filter samples were collected once a day in the Rigi Mountain area of ​​Switzerland (the collection point is located at an altitude of more than 1000m). The sample collection time was from December 1, 2020 to December 31, 2020. Sample collection failed on some dates due to weather and other reasons. See Table 2 for details. After cutting a circular area with a diameter of 20mm from the filter membrane, 12.75mM 0.12g chloroauric acid solution was sprayed on the filter membrane by spraying, and placed under light. The distance between the membrane and the xenon lamp was 5cm. After 20min of illumination, the color of the filter membrane changed from brown to pink purple.

[0076] Place the colored filter membrane in a sealed, light-proof box made of stainless steel. The bottom can be pulled out and inserted to place the sample. A small light bulb is placed on the side to maintain a fixed light intensity. An opening of the same size as the mobile phone camera is set on the top of the box to align the mobile phone camera. The center position of the filter membrane and the center point of the camera hole are in the same vertical direction so that the smartphone camera can fully capture the bottom through the top opening to collect the RGB color intensity of the filter membrane. Place the smartphone at the opening of the box, turn off the flash, and open the Color Swatch software. Read the RGB color intensity value of the filter membrane. Substitute the G value at different concentrations into the effective absorbance formula to obtain EA G The concentration of redox active compounds in the real sample can be calculated based on the standard curve, air flow rate and sampling area. The concentration of redox active compounds in the air in the Rigi Mountains in Switzerland in December is shown in Fig.10 .Depend on Fig. 9 It can be seen that the concentration of redox active compounds in the Rigi Mountains ranges from 0.48 to 2.8 μg·m -3 There are fewer human activities in high altitude areas and higher wind speeds in winter, which leads to relatively low concentrations of redox active compounds, and the concentration of redox active compounds is basically consistent with the changing trend of PM10.

[0077] Table 1 Collection information of PM10 filter samples in Bern, Switzerland

[0078]

[0079] Table 2 Collection information of PM10 filter samples in the Rigi Mountains, Switzerland

[0080]

[0081]

Claims

1. A method for rapid detection of redox active compounds in air, characterized in that: Gold nanoparticles were obtained by in-situ reduction on the filter membrane surface under light, and redox-active compounds in the air were detected using a smartphone based on the color development reaction and photochemical reaction of the gold nanoparticles. The steps include: (1) Collection of standard samples and real air samples Benzoquinone was selected as the standard sample of redox-active compounds in the air. The prepared standard solution of benzoquinone was first passed through a dust generating device to obtain benzoquinone particles, which were then collected on a filter membrane for different periods of time to obtain benzoquinone particles of different masses. The PM10 sample was collected on the filter membrane through a flow air sampler. (2) Establishment of standard curve of air redox active compounds based on smartphone First, collect standard samples of different concentrations, cut a certain circular area, spray 12.75mM chloroauric acid solution on the filter membrane by spraying, and place it under light. The distance between the filter membrane and the xenon lamp is 5cm. After a certain period of light exposure, the color of the filter membrane changes from brown to pink purple; The color-developed filter membrane is placed in a sealed, light-proof box made of stainless steel. The bottom of the box can be pulled out and inserted to place the sample. A small light bulb is placed on the side to maintain a fixed light intensity. There is an opening on the top of the box that is the same size as the mobile phone camera, which is used to align the mobile phone camera. The center position of the filter membrane and the center point of the camera hole are in the same vertical direction so that the camera of the smartphone can fully capture the bottom through the top opening to collect the RGB color intensity of the filter membrane; Place the phone at the opening of the box and open the Color Swatch software; read the RGB color intensity value of the filter; Select the color average of the G component and define the effective absorbance EA G As the dependent variable, establish EA G The quantitative relationship between the concentration of isoquinone and the concentration of isoquinone is plotted as the independent variable. G is the standard curve of the dependent variable; (3) Substitute the G value of the PM10 air sample collected according to steps (1) and (2) into the above standard curve, and calculate the redox active compounds in the real sample based on the air flow rate and sampling area.

2. The method for rapid detection of redox active compounds in air according to claim 1, characterized in that The above filter membrane is a glass fiber membrane with a filter area range of 78.5-15394mm 2 .

3. The method for rapid detection of redox active compounds in air according to claim 1, characterized in that A 100 ppm concentration of benzoquinone solution was selected, and the collection time was 5-180 min. The mass on the filter membrane was measured by the total organic carbon method. The specific process of the total organic carbon method was: first extract the benzoquinone particles on the filter membrane in deionized water and then measure the water-soluble organic carbon on the filter membrane to obtain the benzoquinone concentration per unit area of ​​the filter membrane.

4. The method for rapid detection of redox active compounds in air according to claim 1, characterized in that To collect real PM10 samples, the filter membrane must first be baked at 450°C for 12 hours, cooled to room temperature and dried, and then collected on the filter membrane through a flow air sampler with a sampling flow rate of 500L / min. After the sample is collected, it must be sealed with aluminum foil and stored in a -20°C refrigerator for later use.

5. The method for rapid detection of redox active compounds in air according to claim 1, characterized in that The standard sample cut area is 78.5-1962mm 2 , 12.75mM chloroauric acid solution was sprayed on the filter membrane with a spraying mass of 0.12-0.3g.

6. The method for rapid detection of redox active compounds in air according to claim 1, characterized in that The photochemical reaction was stimulated by a xenon lamp with an illumination time of 10-30 minutes.

7. The method for rapid detection of redox active compounds in air according to claim 1, characterized in that The flashlight was turned off when the mobile phone read the RGB color intensity, and the linear concentration range of benzoquinone particles was 0.026-0.49μg / mm 2 , E.A. G The linear relationship with benzoquinone concentration is EA G =0.1897x+0.0013,R 2 =0.973.

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