A real-time monitoring and analysis system for pollutant degradation and its application in antibiotic pollutant analysis.

Abstract

This invention belongs to the field of mass spectrometry analysis technology, specifically relating to a real-time monitoring and analysis system for pollutant degradation. It includes a photocatalytic device unit, a DC high-voltage device unit, a three-layer capillary, and a mass spectrometry detection unit connected in sequence. The three-layer capillary consists of an outer capillary, a middle capillary, and an inner capillary. The photocatalytic device unit, under illumination, uses a photocatalytic degradation cell for antibiotic pollutants and is connected to the DC high-voltage device unit via a conduit. One end of the DC high-voltage device unit is connected to the photocatalytic device unit, and the other end is connected to the three-layer capillary. The DC high-voltage device unit is also connected to a high-voltage power supply, sheath gas, and sheath fluid. This invention enables highly sensitive real-time online detection of the environmental pollutant degradation process.

Description

Technical Field

[0001] This invention belongs to the field of mass spectrometry analysis technology, specifically relating to a real-time monitoring and analysis system for pollutant degradation and its application in the analysis of antibiotic pollutants. Background Technology

[0002] Roxithromycin is a semi-synthetic macrolide antibiotic with the chemical name 9E-[O-[(2-methoxyethoxy)-methyloxime]erythromycin and the molecular formula C. 41 H 76 N2O 15 Roxithromycin is widely present in aquatic environments. Roxithromycin and its metabolites can accumulate in aquatic animals, leading to biochemical dysfunction in aquatic animals, posing risks to aquatic and terrestrial ecosystems, and further endangering human health.

[0003] Real-time online technology mainly combines photocatalytic degradation devices with label-free high-resolution mass spectrometry to monitor the degradation process of antibiotic pollutants in real time. It provides a rapid and sensitive analytical method for detecting the degradation process of roxithromycin. This technology can achieve continuous online monitoring of pollutant degradation. This real-time monitoring overcomes the time lag problem of traditional manual sampling and analysis methods and avoids the phenomena of data discontinuity and incompleteness during the monitoring process. Summary of the Invention

[0004] The purpose of this invention is to provide a real-time monitoring and analysis system for pollutant degradation and its application in antibiotic pollutant analysis. This system enables highly sensitive analysis of the degradation process of environmental pollutants in real time. A peristaltic pump introduces the degradation liquid from the degradation tank into a three-layer capillary tube. The degradation liquid is transported in the capillary tube and forms charged droplets. The sheath gas and sheath liquid assist each other to achieve better ionization efficiency of the charged droplets. With the addition of a DC high-voltage power supply, the system enters the mass spectrometry detection unit for mass spectrometry detection and analysis.

[0005] The specific technical solution adopted by this invention is as follows:

[0006] A real-time monitoring and analysis system for pollutant degradation includes a photocatalytic device unit, a DC high-voltage device unit, a three-layer capillary, and a mass spectrometry detection unit connected in sequence; the three-layer capillary is divided into an outer capillary, a middle capillary, and an inner capillary.

[0007] The photocatalytic device unit, under illumination, employs a degradation pool for the photocatalytic degradation of antibiotic pollutants and is connected to a DC high-voltage device unit via a conduit.

[0008] One end of the DC high voltage device unit is connected to the photocatalytic device unit, and the other end of the DC high voltage device unit is connected to the three-layer capillary tube. The DC high voltage device unit is also connected to a high voltage power supply, sheath gas, and sheath fluid.

[0009] One end of the three-layer capillary is connected to the DC high-voltage device unit, and the other end of the three-layer capillary is a mass spectrometry electrospray needle, one end of which is connected to the mass spectrometry detection unit.

[0010] The light intensity of the photocatalytic device unit is 6.379 mW / cm². 2 .

[0011] The photocatalytic device unit also includes a peristaltic pump with a flow rate of 1-10 μL / min.

[0012] The distance between the mass spectrometer electro-spray needle and the inlet of the mass spectrometer detection unit is 5-20 mm.

[0013] The inner capillary of the three-layer capillary has an inner diameter of 30-60 μm, the middle capillary has an inner diameter of 200-300 μm, and the outer capillary has an inner diameter of 500-600 μm.

[0014] The length of each of the three capillary layers is 10-100cm.

[0015] The high-voltage power supply is a DC high-voltage power supply with a voltage value of ±1-5kV.

[0016] The three-layer capillary is located at one end of the mass spectrometer electrospray needle. The outlet end of the middle capillary is 5 mm longer than the inner capillary. The outer capillary and the middle capillary are connected by a sheath gas line, and the outer capillary is 1 mm shorter than the middle capillary, which is used to load nitrogen gas.

[0017] Preferably, the sheath fluid is methanol, a volatile solvent, and the sheath gas is nitrogen.

[0018] The application of a real-time monitoring and analysis system for pollutant degradation in the real-time monitoring and analysis of the degradation process of roxithromycin antibiotic pollutants includes the following steps:

[0019] At a light intensity of 6.379 mW / cm 2 Under irradiation, 1 mg / L roxithromycin antibiotic was photocatalytically degraded in pure water for 40 min in the photodegradation unit. The pollutants and their degradation solution in the degradation tank were introduced into a three-layer capillary through a peristaltic pump. Sheath fluid (methanol) and sheath gas (nitrogen) were added to the three-layer capillary. The degradation process was monitored and analyzed in real time by a mass spectrometry detection unit through a mass spectrometry electrospray needle and a DC high voltage power supply.

[0020] Preferably, the antibiotic includes one of tetracyclines, macrolides, penicillins, and quinolones.

[0021] More preferably, the antibiotic contaminant includes at least one of roxithromycin, lincomycin, clarithromycin, norfloxacin, and moxifloxacin. Roxithromycin is preferred as the antibiotic contaminant.

[0022] The technical effects achieved by this invention are as follows:

[0023] This invention discloses a real-time monitoring and analysis system for pollutant degradation and its application in antibiotic pollutant analysis. It combines a photocatalytic degradation device with high-resolution atmospheric pressure mass spectrometry to monitor the degradation of antibiotic pollutants in real time, providing a rapid and sensitive analytical method for monitoring the degradation process of roxithromycin. This method is simple to operate, requires no complex sample pretreatment or chromatographic separation, offers fast analysis speed, high sensitivity, and can fully realize online analysis and real-time monitoring of pollutant degradation processes. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the high-resolution atmospheric pressure mass spectrometry online detection device according to an embodiment of the present invention;

[0025] Figure 2 This is a structural diagram of the high-resolution atmospheric pressure mass spectrometry online detection device according to an embodiment of the present invention;

[0026] Figure 3 This invention relates to an online detection system for the degradation and extraction of roxithromycin using a real-time pollutant degradation analysis method.

[0027] Figure 4 This is a diagram showing the online detection mode of the real-time monitoring and analysis system for pollutant degradation according to an embodiment of the present invention;

[0028] The attached diagram lists the components represented by each number as follows:

[0029] 1. Illumination device; 2. Degradation tank; 3. Pollutant degradation liquid channel; 4. Methanol; 5. DC high voltage device; 6. Sheath liquid channel; 7. Nitrogen; 8. Sheath gas channel; 9. High-resolution mass spectrometry. Detailed Implementation

[0030] To make the objectives and advantages of this invention clearer, the invention will be specifically described below with reference to embodiments. It should be understood that the following text is merely used to describe one or more specific embodiments of the invention and does not strictly limit the scope of protection specifically claimed by the invention.

[0031] Example 1:

[0032] like Figures 1-2As shown, a real-time monitoring and analysis system for pollutant degradation includes photocatalytic device units 1 and 2, DC high voltage device unit 5, three-layer capillary tubes 3, 7, and 8, and mass spectrometry detection unit 9 connected in sequence; the three-layer capillary tubes are divided into an outer capillary tube, a middle capillary tube, and an inner capillary tube, which correspond to the pollutant degradation liquid channel 3, the sheath liquid channel 6, and the sheath gas channel 8, respectively.

[0033] The photocatalytic device unit is located under the illumination device 1 and uses the photocatalytic degradation pool 2 to degrade antibiotic pollutants. It is connected to the DC high voltage device unit 5 through the pollutant degradation liquid channel 3 conduit.

[0034] One end of the DC high voltage device unit 5 is connected to the photocatalytic device unit 2, and the other end of the DC high voltage device unit 5 is connected to the three-layer capillary tube. The three-layer capillary tube consists of a pollutant degradation liquid channel 3, a sheath liquid channel 6, and a sheath gas channel 8. The DC high voltage device unit 5 is also connected to the sheath liquid 6 and the sheath gas 8. The sheath liquid is methanol 4 and the sheath gas is nitrogen 7.

[0035] One end of the three-layer capillary is connected to the DC high voltage device unit 5, and the other end of the three-layer capillary is a mass spectrometry electrospray needle, one end of which is connected to the high-resolution mass spectrometry unit 9.

[0036] like Figure 2 As shown, in the illumination device 1, pollutants are degraded in the photodegradation cell 2. A precision peristaltic pump introduces the pollutant degradation liquid into the pollutant degradation liquid channel 3. The DC high-voltage device unit 5 is a conductive metal component connected to a three-layer capillary tube as the pollutant degradation liquid input pipeline. The flow rate controls the distribution and analysis speed of the degradation liquid in the pipeline. A high-voltage power supply applies a DC high-voltage electric field through the DC high-voltage device unit, charging the flowing droplets. Sheath fluid 6, connected to the DC high-voltage device unit 5, enters the middle capillary tube. The degradation liquid is focused and separated by the surrounding sheath fluid 6 and flows along the axis towards the outlet. Under the action of the high-voltage electric field 5, these substances form charged droplets. The sheath gas 8 pipeline, connected to the DC high-voltage device unit 5, enters the outer capillary tube to load nitrogen gas 7, assisting in the solvent evaporation of the charged droplets to achieve better power efficiency. The other end of the three-layer capillary tube serves as a mass spectrometry electrospray needle. The degradation solution enters the inner capillary for transport and forms charged droplets, which then enter the mass spectrometry detection unit 9 for detection and analysis.

[0037] The light intensity of the photocatalytic device unit is 6.379 mW / cm². 2 .

[0038] The photocatalytic device unit also includes a peristaltic pump with a flow rate of 1-10 μL / min.

[0039] The distance between the mass spectrometer electrospray needle and the inlet of the mass spectrometer detection unit is 5-20 mm.

[0040] The inner capillary of the three-layer capillary has an inner diameter of 30-60 μm, the middle capillary has an inner diameter of 200-300 μm, and the outer capillary has an inner diameter of 500-600 μm.

[0041] The lengths of the three capillary layers are all 10-100cm.

[0042] The high-voltage power supply is a DC high-voltage power supply with a voltage value of ±1-5kV.

[0043] In this embodiment, the analysis system consists of a photocatalytic device unit, a DC high-voltage device unit, a three-layer capillary, and a mass spectrometry detection unit, as follows: Figure 1 As shown; the peristaltic pump flow rate is 3 μL / min, the distance between the mass spectrometer electrospray needle and the inlet of the mass spectrometer detection unit is 10 mm, the inner capillary of the three-layer capillary has an inner diameter of 50 μm and an outer diameter of 220 μm, the middle capillary has an inner diameter of 250 μm and an outer diameter of 363 μm, and the outer capillary has an inner diameter of 530 μm and an outer diameter of 680 μm, the sheath fluid flow rate is 15 μL / min, the sheath gas pressure is 0.5 MPa, and the high-voltage power supply is a DC high-voltage power supply with a voltage of +3 kV.

[0044] The three capillary layers are located at one end of the mass spectrometer electrospray needle. The outlet end of the middle capillary is 5 mm longer than that of the inner capillary. The degradation liquid can be focused and separated by the surrounding sheath fluid and flow along the axis to the outlet. Under the action of the high voltage electric field, these substances form charged droplets. The outer capillary and the middle capillary are connected by a sheath gas channel. The outer capillary is 1 mm shorter than the middle capillary and is used to load nitrogen gas to assist the solvent evaporation of the charged droplets to obtain better power efficiency.

[0045] Example 2:

[0046] The application of a real-time monitoring and analysis system for pollutant degradation in the real-time monitoring and analysis of the degradation process of roxithromycin antibiotic pollutants includes the following steps:

[0047] Solution preparation:

[0048] Accurately weigh 10 mg of roxithromycin standard using an analytical balance, and place the weighed roxithromycin into a 10 mL volumetric flask protected from light. Dissolve the roxithromycin in an appropriate amount of methanol, first adding a small amount of solvent, and then shaking thoroughly to completely dissolve the roxithromycin. Make up the volume to 10 mL to obtain 1 mg / mL roxithromycin.

[0049] Accurately pipette 50 μL of 1 mg / mL roxithromycin solution and transfer the solution to a 50 mL volumetric flask. Dilute to 50 mL with ultrapure water and mix thoroughly to obtain 50 mL of 1 mg / L roxithromycin aqueous solution.

[0050] 50 mL of 1 mg / L roxithromycin was added to the photocatalytic degradation cell at a light intensity of 6.379 mW / cm². 2 Under irradiation, 1 mg / L roxithromycin ( m / z 837.53) Antibiotics were photocatalytically degraded for 40 minutes in a photodegradation unit under pure water medium. The pollutants and their degradation liquid in the degradation tank were introduced into a three-layer capillary through a peristaltic pump. Sheath fluid (methanol) and sheath gas (nitrogen) were added to the three-layer capillary. The degradation process was monitored and analyzed in real time by a mass spectrometer electrospray needle and a DC high-voltage power supply in positive ion mode.

[0051] To investigate the dynamic changes in the degradation process of the antibiotic roxithromycin, an open-circuit mass spectrometer at ambient pressure was used for real-time online monitoring of the degradation process. In this embodiment, the degradation changes of roxithromycin were monitored to allow for real-time observation and analysis of the degradation rate.

[0052] Example 3:

[0053] Based on Example 2, the parameters of the degradation device were optimized:

[0054] (1) Optimization of gas flow rate

[0055] This study used nitrogen as the sheath gas, which promotes the ionization of charged droplets. The effects of different sheath gas sizes on pollutant degradation analysis were investigated and compared. The results showed that when the nitrogen content was too low, the charged droplets were not completely ionized, resulting in a weak target signal intensity. As the carrier gas intensity increased, both the total ion intensity and the target ion intensity increased. The strongest signal intensity was observed in the degradation solution when the nitrogen concentration was 0.5 MPa. When the carrier gas intensity was greater than 0.5 MPa, the target ion intensity weakened because excessively high carrier gas concentrations could cause charged droplets to be blown away, making it difficult for charged ions to enter the mass spectrometer for detection. Therefore, 0.5 MPa was chosen as the optimal sheath gas intensity for subsequent experiments.

[0056] (2) Optimization of sheath fluid flow rate

[0057] The sheath fluid flow rate is a crucial factor affecting the signal of the degradation solution. Adjusting the flow rates of the peristaltic pump and the sheath fluid allows for a more balanced ion distribution within the detection system, facilitating detection. Excessive flow rate leads to over-dilution of the sample, reducing the signal of the degradation solution; conversely, insufficient flow rate prevents complete ionization of the degradation solution during real-time online monitoring and fails to generate a stable signal. At a sheath fluid flow rate of 15 μL / min, the device generates a stable signal with a strong detection of the target ion. Increasing the flow rate reduces the signal of the target pollutant per unit time, as the target substance is over-diluted, resulting in a decrease in signal intensity. Within the sheath fluid flow rate range of 10-15 μL / min, the mass spectrometry signal decreases with decreasing flow rate. Therefore, after optimization, 15 μL / min was selected as the optimal sheath fluid flow rate for subsequent experiments.

[0058] (3) DC voltage optimization

[0059] The magnitude of the applied high voltage determines the ionization efficiency of the target substance. Lower applied voltages result in lower ionization efficiency, or even no ionization at all, severely impacting the target substance's response intensity and sensitivity. Conversely, higher applied voltages increase ionization efficiency, but voltages exceeding a certain range can easily cause capillary tip discharge, negatively affecting the signal-to-noise ratio and hindering the analysis of degradation solutions. This study compared the effects of different high-voltage electric fields (0, 0.5, 1, 1.5, 2.0, 2.5, 3.0, 3.5, and 4.0 kV) on the target ion intensity. Results showed that at lower voltages, the mass spectrometry signal was weak and unstable, and dripping occurred at the capillary outlet. With increasing high-voltage electric field, the obtained mass spectrometry signal intensity gradually increased, reaching its highest at +3 kV. When the applied high-voltage electric field exceeded 3 kV, the mass spectrometry signal weakened; therefore, 3 kV was chosen as the optimal applied voltage for subsequent experiments.

[0060] Example 4:

[0061] Based on Examples 1-3, this example discloses the degradation performance of roxithromycin under different light exposure times:

[0062] To further investigate the degradation efficiency of roxithromycin at different time points, four main degradation times were selected and recorded. Mass spectrometry analysis revealed that the degradation solution changed significantly over time. The degradation rates of pollutants were recorded at light exposure times of 0 min, 10 min, 25 min, and 40 min.

[0063] The following experimental parameters were used: peristaltic pump flow rate of 3 μL / min; sheath fluid flow rate of 15 μL / min; sheath gas pressure of 0.5 MPa; DC high voltage of 3 kV; detection mode of positive ion; and photocatalytic device with a light intensity of 6.379 mW / cm². 2 When the sample was irradiated in the photodegradation cell for 0 minutes, the degradation rate of roxithromycin was 0%.

[0064] The following experimental parameters were used: peristaltic pump flow rate of 3 μL / min; sheath fluid flow rate of 15 μL / min; sheath gas pressure of 0.5 MPa; DC high voltage of 3 kV; detection mode of positive ion; and photocatalytic device with a light intensity of 6.379 mW / cm². 2 When the sample was irradiated in a photodegradation cell for 10 minutes, the degradation rate of roxithromycin was 83.41%.

[0065] The following experimental parameters were used: peristaltic pump flow rate of 3 μL / min; sheath fluid flow rate of 15 μL / min; sheath gas pressure of 0.5 MPa; DC high voltage of 3 kV; detection mode of positive ion; and photocatalytic device with a light intensity of 6.379 mW / cm². 2 When the sample was irradiated in the photodegradation cell for 25 minutes, the degradation rate of roxithromycin was 95.98%.

[0066] The following experimental parameters were used: peristaltic pump flow rate of 3 μL / min; sheath fluid flow rate of 15 μL / min; sheath gas pressure of 0.5 MPa; DC high voltage of 3 kV; detection mode of positive ion; and photocatalytic device with a light intensity of 6.379 mW / cm². 2 When the sample was irradiated in the photodegradation cell for 40 minutes, the degradation rate of roxithromycin was 98.36%.

[0067] Experimental results

[0068] Depend on Figure 3 It is known that in positive ion mode m / z The signal of roxithromycin was measured at 837.5315, with a response value of 10. 6 Under light exposure time of 0-15 min, roxithromycin showed a significant degradation trend, and its degradation slowed down after 15 min.

[0069] Depend on Figure 4 It is known that in positive ion mode m / z Roxithromycin was detected at 837.5328.

[0070] The above description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described or explained in this invention are implemented according to conventional methods in the art unless otherwise specified or limited.

Claims

1. A real-time monitoring and analysis system for antibiotic pollutant degradation, characterized in that: It includes a photocatalytic device unit, a DC high-voltage device unit, a three-layer capillary, and a mass spectrometry detection unit connected in sequence; the three-layer capillary is divided into an outer capillary, a middle capillary, and an inner capillary. The photocatalytic device unit also includes a peristaltic pump with a flow rate of 3 μL / min; The photocatalytic device unit, under illumination, employs a degradation pool for the photocatalytic degradation of antibiotic pollutants and is connected to a DC high-voltage device unit via a conduit. One end of the DC high voltage device unit is connected to the photocatalytic device unit, and the other end of the DC high voltage device unit is connected to the three-layer capillary tube. The DC high voltage device unit is also connected to a high voltage power supply, sheath gas, and sheath fluid. One end of the three-layer capillary is connected to the DC high voltage device unit, and the other end of the three-layer capillary is a mass spectrometer electrospray needle, one end of which is connected to the mass spectrometer detection unit. The three-layer capillary is located at one end of the mass spectrometer electrospray needle. The outlet end of the middle capillary is 5 mm longer than the inner capillary. The outer capillary is connected to the middle capillary via a sheath gas line, and the outer capillary is 1 mm shorter than the middle capillary. This line is used to load nitrogen gas. The distance between the mass spectrometer electrospray needle and the inlet of the mass spectrometer detection unit is 10 mm. The inner capillary of the three-layer capillary has an inner diameter of 50 μm and an outer diameter of 220 μm, the middle capillary has an inner diameter of 250 μm and an outer diameter of 363 μm, and the outer capillary has an inner diameter of 530 μm and an outer diameter of 680 μm. The sheath fluid flow rate is 15 μL / min, the sheath gas pressure is 0.5 MPa, and the high-voltage power supply is a DC high-voltage power supply with a voltage of 3 kV.

2. The real-time monitoring and analysis system for antibiotic pollutant degradation according to claim 1, characterized in that: The light intensity of the photocatalytic device unit is 6.379 mW / cm². 2 .

3. The real-time monitoring and analysis system for antibiotic pollutant degradation according to claim 1, characterized in that: The length of each of the three capillary layers is 10-100cm.

4. The application of the real-time monitoring and analysis system for antibiotic pollutant degradation according to any one of claims 1-3 in the real-time monitoring and analysis of the degradation process of roxithromycin antibiotic pollutants.

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