Bamboo-based photothermal evaporation enrichment monitoring device, preparation method thereof and application of the device in monitoring drugs in river basin

Abstract

The present application relates to a bamboo-based photothermal evaporation enrichment monitoring device and its preparation method and river basin drug monitoring application, the preparation method comprises: bamboo pieces are treated by acidic deep eutectic solution, loaded with ZnO and carbonized on the surface for a short time to obtain a bamboo-based solar evaporator; the bamboo-based solar evaporator is immersed in a pyrrole / rGO / AuNPs water mixture to construct a PPy-rGO-AuNPs conductive amplification layer; then it is placed in a Tris buffer containing 6-MAM, MOR and dopamine for 1-6h reaction and elution of the template to construct a 6-MAM / MOR double-template PDA molecularly imprinted recognition layer, obtaining a drug-responsive bamboo-based evaporation sensing unit; several evaporation sensing units are inserted into the circular pearl cotton in a staggered manner to form a bamboo-based evaporation monitoring array, and embedded into a life buoy type floating base; the evaporation monitoring array is integrated with an EIS impedance measurement module, a wireless communication module, a photovoltaic power supply module and a condensate water collection module to obtain a bamboo-based photothermal evaporation enrichment monitoring device. The present application can be used for in-situ evaporation enrichment, impedance identification and wireless early warning of heroin source drug markers in river basins.

Description

Technical Field

[0001] This invention belongs to the field of solar photothermal conversion and water environment electrochemical monitoring technology, specifically relating to a bamboo-based photothermal evaporation enrichment monitoring device, its preparation method, and its application in watershed drug monitoring. Background Technology

[0002] Freshwater is a strategic resource essential for human survival, and monitoring urban rivers and watersheds is a crucial link in maintaining regional ecological and public safety. Currently, watersheds face challenges such as low concentrations of micropollutants, high toxicity, complex migration pathways, and difficulties in on-site monitoring. Besides conventional micropollutants like organic dyes, antibiotics, and bacteria, heroin-derived drug markers and their metabolites can also enter urban water systems through domestic sewage, combined sewer overflows, and tributary flows, exhibiting characteristics such as low concentrations, large spatial and temporal fluctuations, and a strong need for early warning. Therefore, developing a floating water evaporation monitoring device that combines water evaporation enrichment, drug marker identification, and wireless in-situ monitoring capabilities is of great significance.

[0003] Currently, most mainstream solar evaporators adopt a dual-layer structure design of photothermal layer / water transport channel, which enhances the evaporation rate through localized heat effect. For example, patent document CN116623361B discloses the use of a tree-inspired woven fiber skeleton and the use of polypyrrole-modified Tencel yarn for water supply to generate heat and evaporate water; another example is patent document CN119059595A, which reports the preparation of a hydrogel interface evaporator using polyvinyl alcohol and nanocellulose, endowing the hydrogel with broad-spectrum absorption properties and seawater desalination performance. However, the above devices mainly focus on evaporation efficiency or water purification performance, and have not yet integrated evaporation enrichment, specific molecule recognition, EIS impedance readout, and floating array deployment into a complete device for watershed drug monitoring.

[0004] Among existing drug detection technologies, molecular imprinting and electrochemical sensing are commonly used approaches. For example, patent document CN101788489B discloses a molecularly imprinted polymer sensitive film doped with noble metal nanoparticles for the detection of drugs such as heroin, morphine, and cocaine; patent document CN114674886B discloses a molecularly imprinted electrochemical sensor for detecting ecstasy components; and patent document CN105548151B discloses a method for detecting codeine based on the combined use of ionic iridium complex electrochemiluminescence and molecular imprinting recognition technology. These technologies demonstrate the feasibility of molecular imprinting recognition in drug detection, but they typically rely on independent electrodes, laboratory sample processing, or fixed detection scenarios, making them difficult to directly adapt to long-term floating, continuous water intake, solar self-powered, and multi-point wireless early warning systems in open waterways.

[0005] Therefore, a new bamboo-based photothermal evaporation enrichment monitoring device is still needed, which enables the bamboo-based evaporator to perform continuous water absorption, solar evaporation and interfacial enrichment functions, enables the PPy-rGO-AuNPs conductive layer and PDA molecular imprinted layer to perform drug marker identification and impedance response functions, and enables in-situ watershed monitoring through floating array, EIS module, wireless communication and photovoltaic power supply. Summary of the Invention

[0006] Based on the above-mentioned shortcomings and deficiencies in the existing technology, one of the objectives of this invention is to provide a bamboo-based photothermal evaporation enrichment monitoring device, its preparation method, and its application in watershed drug monitoring. The bamboo-based photothermal evaporation enrichment monitoring device simultaneously possesses the capabilities of solar water evaporation, drug marker enrichment identification, EIS impedance monitoring, and floating array deployment.

[0007] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: A method for preparing a bamboo-based photothermal evaporation enrichment monitoring device includes the following steps: (1) After washing and drying the bamboo strips, soak them in an acidic deep eutectic solution and heat them at 80-100℃ for 5-8 hours. Then wash them until neutral and dry them to obtain lignin-free bamboo strips. Soak the lignin-free bamboo strips in a ZnO / water mixed solution for 0.5-1 hours, take them out and air dry them naturally, and place them on a heating platform at 250-300℃ for 30-60 seconds to obtain a bamboo-based solar evaporator. By treating the bamboo strips with acidic deep eutectic solution to remove lignin, ZnO loading and short-time surface carbonization, a bamboo-based solar evaporator with the ability to retain the multi-level pores of bamboo and photothermal evaporation is formed. (2) Immerse the bamboo-based solar evaporator in a pyrrole / rGO / AuNPs aqueous solution and add FeCl3 aqueous solution for oxidative polymerization for 0.5-2h to obtain a bamboo-based solar evaporator with a PPy-rGO-AuNPs conductive amplification layer; then place it in a Tris buffer containing 6-monoacetylmorphine 6-MAM, morphine MOR and dopamine for 1-6h, and then elute the 6-MAM and MOR template molecules to obtain a drug-responsive bamboo-based evaporation sensing unit with a 6-MAM / MOR dual template PDA molecular imprint recognition layer; (3) Several drug-responsive bamboo-based evaporation sensing units are interleaved and inserted into a circular pearl cotton to form a bamboo-based evaporation monitoring array, and the bamboo-based evaporation monitoring array is embedded in a ring-shaped floating substrate; (4) The bamboo-based evaporation monitoring array is integrated with the EIS impedance measurement module, wireless communication module, photovoltaic power supply module and condensate collection module to obtain a bamboo-based photothermal evaporation enrichment monitoring device that can float, be powered and transmit signals.

[0008] As a preferred embodiment, the acidic deep eutectic solution comprises choline chloride and oxalic acid in a molar ratio of 1:(1-4).

[0009] As a preferred embodiment, in the pyrrole / rGO / AuNPs aqueous mixture, the concentration of pyrrole is 0.05-0.20 mol / L, the concentration of rGO is 0.5-2.0 mg / mL, and the concentration of AuNPs (calculated as gold) is 0.1-1.0 mmol / L; The concentration of the FeCl3 aqueous solution is 0.05-0.20 mol / L.

[0010] As a preferred embodiment, the Tris buffer has a pH of 8.0-8.8, a dopamine concentration of 1-5 mg / mL, a molar ratio of 6-MAM to MOR of 1:(0.5-2), and a molar ratio of total template molecules of 6-MAM and MOR to dopamine of 1:(50-200).

[0011] As a preferred embodiment, in step (2), the elution solution for the template molecule is a mixture of ethanol / acetic acid or methanol / acetic acid with a volume ratio of 9:1, and the elution time is 0.5-2h.

[0012] As a preferred embodiment, the number of the drug-responsive bamboo-based evaporation sensing units is 3-12, preferably 9; if there are fewer than 3 units, the effective evaporation and sampling area is insufficient, and if there are more than 12 units, the array is too dense and affects vapor dissipation and impedance stability.

[0013] As a preferred option, the drug-responsive bamboo-based evaporation sensing unit is embedded in the inner ring of the ring-shaped floating substrate.

[0014] As a preferred embodiment, the outer diameter of the ring-shaped floating base is 410mm, the inner diameter is 240mm, and the thickness is 70mm; the diameter of the circular pearl cotton is 240mm.

[0015] As a preferred embodiment, the EIS impedance measurement module and the wireless communication module are located inside the ring-shaped floating substrate, and the photovoltaic power supply module is located on the surface of the ring-shaped floating substrate; the condensate collection module is located above the bamboo-based evaporation monitoring array.

[0016] As a preferred embodiment, the EIS impedance monitoring uses charge transfer resistance Rct as the main signal parameter, and the higher the concentration of drug markers, the larger Rct is.

[0017] The present invention also provides a bamboo-based photothermal evaporation enrichment monitoring device prepared by the preparation method described in any of the above schemes.

[0018] As a preferred option, the bamboo-based photothermal evaporation enrichment monitoring device has an evaporation flux of no less than 30 kg / m² under a single solar irradiation.

[0019] The present invention also provides a watershed drug monitoring application for the bamboo-based photothermal evaporation enrichment monitoring device described above, which is used for in-situ evaporation enrichment, EIS impedance monitoring, and wireless early warning of heroin-derived drug markers in watershed water bodies.

[0020] Compared with the prior art, the beneficial effects of this invention are: (1) This invention utilizes the synergistic evaporation mechanism of bamboo's multi-level channels, ZnO nanoparticles and surface carbonization layer, which can achieve an evaporation flux of no less than 30 kg / m² under a single solar irradiation, realizing continuous water absorption, interface renewal and evaporation enrichment; (2) The present invention determines that PPy-rGO-AuNPs are used as the conductive amplification layer and 6-MAM / MOR dual-template PDA molecular imprinted polymer is used as the recognition layer, so that the bamboo-based vaporizer is transformed from a single evaporation unit into a drug-responsive evaporation sensing unit. (3) In this invention, Rct is used as the core indicator for EIS monitoring. The higher the concentration of drug marker, the larger the Rct. The monitoring stability for different concentration gradients is R²=0.99, and the monitoring accuracy reaches 1ng / L. (4) The present invention forms a floating array by adjusting the number of sensing units and integrates it with photovoltaic power supply, wireless communication and condensate collection modules, which is suitable for distributed deployment and in-situ early warning in the upper, middle and lower reaches of the basin. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the bamboo-based photothermal evaporation enrichment monitoring device of the present invention (taking a nine-unit array as an example). Figure 2 This is a schematic diagram of the structure of the drug-responsive bamboo-based evaporation sensing unit of the present invention; Figure 3 This is a schematic diagram illustrating the EIS impedance monitoring principle of the present invention; Figure 4 This is a comparison chart of the evaporation performance of Embodiment 1 of the present invention and related comparative examples under a single solar irradiation. Figure 5 This is a comparison graph of the charge transfer resistance response of Embodiment 1 of the present invention and related comparative examples to different concentrations of drug markers; Figure 6 This is an EIS Nyquist curve diagram of Example 1 of the present invention at different concentrations of drug markers; Figure 7 This is a comparison chart showing the impact of different numbers of sensing units on evaporation and monitoring performance in this invention. Detailed Implementation

[0022] The following provides a detailed description of the bamboo-based photothermal evaporation enrichment monitoring device, its preparation method, and its application in watershed drug monitoring.

[0023] This invention uses abundant natural bamboo as raw material, employs an acidic deep eutectic solvent to remove lignin while preserving and widening the multi-level pores of the bamboo, and then forms a bamboo-based solar evaporator through ZnO nanoparticle loading and short-term surface carbonization. On this basis, a PPy-rGO-AuNPs conductive amplification layer and a 6-MAM / MOR dual-template PDA molecular imprint recognition layer are constructed to obtain a drug-responsive bamboo-based evaporation sensing unit. Furthermore, several sensing units are assembled into a floating array and integrated with EIS impedance measurement, wireless communication, photovoltaic power supply and condensate collection modules to finally form a bamboo-based photothermal evaporation enrichment monitoring device that can be used for in-situ drug monitoring in watersheds.

[0024] Specifically, the preparation method of the bamboo-based photothermal evaporation enrichment monitoring device of the present invention includes the following steps: (1) After washing and drying the bamboo strips, soak them in an acidic deep eutectic solution and heat them at 80-100℃ for 5-8 hours. Then wash them until neutral and dry the resulting material to obtain lignin-free bamboo strips. The acidic deep eutectic solution includes choline chloride and oxalic acid. Soak the lignin-free bamboo strips in a ZnO / water mixed solution for 0.5-1 hours. The bamboo strips adsorb the solution and load ZnO onto the lignin-free bamboo strips. Then air dry them to obtain ZnO / bamboo strips. Place the ZnO / bamboo strips on a heating platform at 250-300℃ for 30-60 seconds to form organic carbonization on the surface to obtain a bamboo-based solar evaporator. (2) Immerse the bamboo-based solar evaporator in a pyrrole / rGO / AuNPs aqueous solution, add FeCl3 aqueous solution and oxidize and polymerize at room temperature for 0.5-2h. After washing and drying, obtain the PPy-rGO-AuNPs conductive amplification layer. Then place it in a Tris buffer containing 6-MAM, MOR and dopamine and react for 1-6h. Then elute with an ethanol / acetic acid mixture or a methanol / acetic acid mixture for 0.5-2h to obtain a 6-MAM / MOR dual-template PDA molecular imprint recognition layer. Finally, obtain the drug-responsive bamboo-based evaporation sensing unit. (3) Insert 3-12 drug-responsive bamboo-based evaporation sensing units alternately into circular pearl cotton to form a bamboo-based evaporation monitoring array; wherein the diameter of the circular pearl cotton is 240mm and it is embedded in the inner ring of the ring-shaped floating substrate; (4) Connect the EIS impedance measurement module to the bamboo-based evaporation monitoring array, connect the wireless communication module to the EIS impedance measurement module, and embed the EIS impedance measurement module and the wireless communication module inside the ring-shaped floating substrate; set a small photovoltaic power generation panel on the surface of the ring-shaped floating substrate, and set a semi-circular acrylic cover and a water storage tank above the bamboo-based evaporation monitoring array to obtain a complete bamboo-based photothermal evaporation enrichment monitoring device.

[0025] The molar ratio of choline chloride to oxalic acid in the above-mentioned acidic deep eutectic solution is 1:(1-4), which can be determined according to the actual application requirements.

[0026] In this process, choline chloride is mixed with oxalic acid and stirred at 40-60℃ for 30-60 minutes to obtain an acidic deep eutectic solution; the specific temperature and time can be determined according to the actual application requirements.

[0027] The solid-liquid ratio of the dried bamboo strips to the acidic deep eutectic solution is (5-10) g: (400-500) mL. The specific solid-liquid ratio can be determined according to the actual application requirements.

[0028] The solid-liquid ratio of the above ZnO / water mixed solution is (1-3) g: (400-500) mL, and the solid-liquid ratio of the lignin-free bamboo chips to the ZnO / water mixed solution is (2-7) g: (400-500) mL. The specific ratio can be determined according to the actual application requirements.

[0029] In the above-mentioned pyrrole / rGO / AuNPs aqueous mixture, the concentration of pyrrole is 0.05-0.20 mol / L, the concentration of rGO is 0.5-2.0 mg / mL, and the concentration of AuNPs (calculated as gold) is 0.1-1.0 mmol / L; the concentration of FeCl3 aqueous solution is 0.05-0.20 mol / L, which can be determined according to the actual application requirements.

[0030] The pH of the above Tris buffer is 8.0-8.8, the dopamine concentration is 1-5 mg / mL, the molar ratio of 6-MAM to MOR is 1:(0.5-2), the molar ratio of total template molecules of 6-MAM and MOR to dopamine is 1:(50-200), the elution buffer for template molecules is a mixture of ethanol / acetic acid or methanol / acetic acid with a volume ratio of 9:1, and the elution time is 0.5-2 h, which can be determined according to the actual application requirements.

[0031] The number of the above-mentioned drug-responsive bamboo-based evaporation sensing units is 3-12, preferably 9. When the number of sensing units is too small, the effective evaporation area and water sampling representativeness are insufficient. When the number of sensing units is too large, the array is too dense, which will affect water vapor dissipation, electrode connection stability and impedance repeatability.

[0032] The bamboo strips of this invention are selected from moso bamboo, thunder bamboo, Ci bamboo or Gang bamboo, and the specific selection can be determined according to actual application requirements.

[0033] The bamboo-based photothermal evaporation enrichment monitoring device prepared by the above preparation method has an evaporation flux of not less than 30 kg / m² under a single solar irradiation. The charge transfer resistance Rct in the EIS test is used as the drug monitoring signal. The higher the concentration of the drug marker, the larger Rct is. The monitoring stability under different drug concentration gradients is R²=0.99, and the monitoring accuracy reaches 1 ng / L.

[0034] The bamboo-based photothermal evaporation enrichment monitoring device of the present invention has excellent water evaporation and in-situ watershed monitoring capabilities. It can utilize the multi-level pores of bamboo to achieve continuous water absorption and interface enrichment, utilize the PPy-rGO-AuNPs conductive layer to improve the impedance response signal, utilize the 6-MAM / MOR dual-template PDA molecular imprint layer to achieve drug marker identification, and achieve multi-point deployment in the watershed through a floating array.

[0035] like Figure 1 As shown, the bamboo-based photothermal evaporation enrichment monitoring device of the present invention includes a lifebuoy-type floating base, a nine-unit bamboo-based evaporation monitoring array, an EIS impedance measurement module, a wireless communication module (RF), a photovoltaic power supply module, a semi-circular acrylic cover, and a water storage tank. The lifebuoy-type floating base provides floating support and waterproof installation space. The bamboo-based evaporation monitoring array is located in its inner circle, the EIS impedance measurement module and the wireless communication module are located inside it, the photovoltaic power supply module is located on its surface, and the semi-circular acrylic cover and the water storage tank are located above the array.

[0036] like Figure 2 As shown, the drug-responsive bamboo-based evaporation sensing unit of the present invention comprises, from the inside out, a bamboo-based solar evaporator, a PPy-rGO-AuNPs conductive amplification layer, and a 6-MAM / MOR dual-template PDA molecular imprint recognition layer. The bamboo-based solar evaporator performs water transport and photothermal evaporation functions, the conductive amplification layer reduces baseline impedance and increases signal strength, and the molecular imprint recognition layer provides recognition cavities matched with 6-MAM and MOR.

[0037] like Figure 3 As shown, the EIS impedance monitoring of this invention uses Rct as the core signal parameter. When 6-MAM and MOR enter the molecularly imprinted pores, interfacial charge transfer is hindered, and Rct increases; the higher the concentration of the target analyte, the more imprinted sites are occupied, and the greater the increase in Rct. Using Rct0 in a blank water body as a benchmark, the change in drug marker concentration can be characterized by ΔRct / Rct0.

[0038] The bamboo-based photothermal evaporation enrichment monitoring device of the present invention is used for watershed drug monitoring. Its main detection target is heroin-derived drug markers in water bodies; 6-MAM is 6-monoacetylmorphine, and MOR is morphine. The detection method is as follows: the device is placed in water bodies or simulated water bodies containing different concentrations of drug markers, the change of Rct is recorded by the EIS impedance measurement module, and quantitative analysis is performed by the linear relationship between ΔRct / Rct0 and the concentration of drug markers.

[0039] The monitoring accuracy test method of the present invention is to increase the concentration of drug markers in a gradient of 1-50 ng / L, record the change of Rct at each gradient, and output the linear relationship between ΔRct / Rct0 and the concentration of drug markers; wherein, the linear relationship of Example 1 is not less than 0.99, and the lowest resolvable concentration is 1 ng / L.

[0040] The following detailed description of the bamboo-based photothermal evaporation enrichment monitoring device, its preparation method, and its application in watershed drug monitoring, through specific embodiments and comparative examples, further illustrates these inventions.

[0041] Example 1: The preparation method of the bamboo-based photothermal evaporation enrichment monitoring device in this embodiment includes the following steps: Choline chloride and oxalic acid (molar ratio 1:2) were placed in a beaker and stirred in a 50°C water bath for 45 min to prepare an acidic deep eutectic solution. Bamboo chips were then washed with water and air-dried at room temperature. 8 g of the bamboo chip precursor material was immersed in 450 mL of the acidic deep eutectic solution and heated in a 90°C water bath for 7 h. Subsequently, the mixture was washed with deionized water until neutral and dried in a 60°C oven to obtain lignin-free bamboo chips. 5g of lignin-free bamboo chips were soaked in 450mL of a 2g / L ZnO / water mixed solution for 0.8h. After being removed, the chips were air-dried at room temperature to obtain ZnO / bamboo chips. The ZnO / bamboo chips were placed on a heating platform at 250℃ for 40 seconds to rapidly carbonize their surface, thus obtaining a bamboo-based solar evaporator. A pyrrole / rGO / AuNPs aqueous mixture was prepared, wherein the concentration of pyrrole was 0.10 mol / L, the concentration of rGO was 1.0 mg / mL, and the concentration of AuNPs (calculated as gold) was 0.5 mmol / L. A bamboo-based solar evaporator was immersed in the mixture, and a 0.10 mol / L FFeCl3 aqueous solution was added. Oxidative polymerization was carried out at room temperature for 1 h. The mixture was then washed and dried to obtain a PPy-rGO-AuNPs conductive amplification layer. Tris buffer solution with pH 8.5 was prepared, in which the dopamine concentration was 2 mg / mL, the molar ratio of 6-MAM to MOR was 1:1, and the molar ratio of the total template molecules of 6-MAM and MOR to dopamine was 1:100. A bamboo-based solar evaporator with a PPy-rGO-AuNPs conductive amplification layer was placed in this solution and reacted for 3 h. Then it was eluted with an ethanol / acetic acid mixture (volume ratio of 9:1) for 1 h to obtain a 6-MAM / MOR dual-template PDA molecular imprint recognition layer, namely a drug-responsive bamboo-based evaporation sensing unit. Nine drug-responsive bamboo-based evaporation sensing units were interleaved and inserted into a 240mm diameter circular pearl cotton to form a bamboo-based evaporation monitoring array; the array was then embedded in a lifebuoy-like floating substrate with an outer diameter of 410mm, an inner diameter of 240mm, and a thickness of 70mm. The EIS impedance measurement module was connected to the bamboo-based evaporation monitoring array, and the wireless communication module was also connected to the EIS impedance measurement module. Both were placed inside the circular floating substrate. A small photovoltaic panel was placed on the surface of the circular floating substrate, covering an area of ​​one-third of the circular surface of the lifebuoy. A semi-circular acrylic cover with a diameter of 250 mm was placed above the bamboo-based evaporation monitoring array, and a water storage tank was set up to collect the evaporation condensate. Finally, a bamboo-based photothermal evaporation enrichment monitoring device was obtained.

[0042] The device obtained in this embodiment has an evaporation flux of 33 kg / m² under a single solar irradiation. EIS testing was performed on the concentration gradient of drug markers from 1 to 50 ng / L. ΔRct / Rct0 showed a linear relationship with the concentration, the monitoring stability was R²=0.99, and the monitoring accuracy reached 1 ng / L.

[0043] Example 2: The preparation method of the bamboo-based photothermal evaporation enrichment monitoring device in this embodiment includes the following steps: Choline chloride and oxalic acid (molar ratio 1:2) were placed in a beaker and stirred in a 45°C water bath for 50 min to prepare an acidic deep eutectic solution. Bamboo chips were then washed with water and air-dried at room temperature. 8 g of the bamboo chip precursor material was immersed in 450 mL of the acidic deep eutectic solution and heated in a 90°C water bath for 7 h. Subsequently, the mixture was washed with deionized water until neutral and dried in a 60°C oven to obtain lignin-free bamboo chips. 5g of lignin-free bamboo chips were soaked in 450mL of a 2g / L ZnO / water mixed solution for 0.8h. After being removed, the chips were air-dried at room temperature to obtain ZnO / bamboo chips. The ZnO / bamboo chips were placed on a heating platform at 260℃ for 40 seconds to rapidly carbonize their surface, thus obtaining a bamboo-based solar evaporator. A pyrrole / rGO / AuNPs aqueous mixture was prepared, wherein the concentration of pyrrole was 0.08 mol / L, the concentration of rGO was 0.8 mg / mL, and the concentration of AuNPs (calculated as gold) was 0.4 mmol / L. A bamboo-based solar evaporator was immersed in the mixture, and a 0.08 mol / L FFeCl3 aqueous solution was added. Oxidative polymerization was carried out at room temperature for 0.5 h. The mixture was then washed and dried to obtain a PPy-rGO-AuNPs conductive amplification layer. Tris buffer solution with pH 8.5 was prepared, in which the dopamine concentration was 2 mg / mL, the molar ratio of 6-MAM to MOR was 1:1, and the molar ratio of the total template molecules of 6-MAM and MOR to dopamine was 1:100. A bamboo-based solar evaporator with a PPy-rGO-AuNPs conductive amplification layer was placed in this solution and reacted for 3 h, followed by elution with an ethanol / acetic acid mixture for 1 h to obtain a drug-responsive bamboo-based evaporation sensing unit. Nine drug-responsive bamboo-based evaporation sensing units were interleaved and inserted into a 240mm diameter circular pearl cotton, and then embedded in a lifebuoy-style floating substrate. After that, an EIS impedance measurement module, a wireless communication module, a photovoltaic power supply module, a semi-circular acrylic cover and a water storage tank were connected to produce a bamboo-based photothermal evaporation enrichment monitoring device.

[0044] The evaporation flux of the device obtained in this embodiment is 31 kg / m² under a single solar irradiation. Due to the shortened polymerization time of the conductive amplification layer, the continuity of the conductive network is lower than that in Example 1. The stability of the drug marker concentration gradient monitoring is R²=0.97, and the monitoring accuracy is 2 ng / L.

[0045] Example 3: The preparation method of the bamboo-based photothermal evaporation enrichment monitoring device in this embodiment includes the following steps: Choline chloride and oxalic acid (molar ratio 1:3) were placed in a beaker and stirred in a 55°C water bath for 35 min to prepare an acidic deep eutectic solution. Bamboo chips were then washed with water and air-dried at room temperature. 8 g of the bamboo chip precursor material was immersed in 450 mL of the acidic deep eutectic solution and heated in a 90°C water bath for 7 h. Subsequently, the mixture was washed with deionized water until neutral and dried in a 60°C oven to obtain lignin-free bamboo chips. 5g of lignin-free bamboo chips were soaked in 450mL of a 2g / L ZnO / water mixed solution for 0.8h. After being removed, the chips were air-dried at room temperature to obtain ZnO / bamboo chips. The ZnO / bamboo chips were placed on a heating platform at 270℃ for 40 seconds to rapidly carbonize their surface, thus obtaining a bamboo-based solar evaporator. A pyrrole / rGO / AuNPs aqueous mixture was prepared, wherein the concentration of pyrrole was 0.10 mol / L, the concentration of rGO was 1.0 mg / mL, and the concentration of AuNPs (calculated as gold) was 0.5 mmol / L. A bamboo-based solar evaporator was immersed in the mixture, and a 0.10 mol / L FFeCl3 aqueous solution was added. Oxidative polymerization was carried out at room temperature for 1 h. The mixture was then washed and dried to obtain a PPy-rGO-AuNPs conductive amplification layer. Tris buffer solution with pH 8.5 was prepared, in which the dopamine concentration was 2 mg / mL, the molar ratio of 6-MAM to MOR was 1:2, and the molar ratio of the total template molecules of 6-MAM and MOR to dopamine was 1:50. A bamboo-based solar evaporator with a PPy-rGO-AuNPs conductive amplification layer was placed in this solution and reacted for 2 h, followed by elution with an ethanol / acetic acid mixture for 1 h to obtain a drug-responsive bamboo-based evaporation sensing unit. Nine drug-responsive bamboo-based evaporation sensing units were interleaved and inserted into a 240mm diameter circular pearl cotton, and then embedded in a lifebuoy-style floating substrate. After that, an EIS impedance measurement module, a wireless communication module, a photovoltaic power supply module, a semi-circular acrylic cover and a water storage tank were connected to produce a bamboo-based photothermal evaporation enrichment monitoring device.

[0046] The evaporation flux of the device obtained in this embodiment under a single solar irradiation is 32 kg / m². Due to the change in template ratio and PDA reaction time, the number of imprint pores and uniformity are slightly lower than in Example 1. The stability of drug marker concentration gradient monitoring is R²=0.98, and the monitoring accuracy is 2 ng / L.

[0047] Example 4: The preparation method of the six-unit bamboo-based photothermal evaporation enrichment monitoring device in this embodiment includes the following steps: Choline chloride and oxalic acid (molar ratio 1:2) were placed in a beaker and stirred in a 50°C water bath for 45 min to prepare an acidic deep eutectic solution. Bamboo chips were then washed with water and air-dried at room temperature. 8 g of the bamboo chip precursor material was immersed in 450 mL of the acidic deep eutectic solution and heated in a 90°C water bath for 7 h. Subsequently, the mixture was washed with deionized water until neutral and dried in a 60°C oven to obtain lignin-free bamboo chips. 5g of lignin-free bamboo chips were soaked in 450mL of a 2g / L ZnO / water mixed solution for 0.8h. After being removed and air-dried, the chips were placed on a 250℃ heating platform for 40 seconds to obtain a bamboo-based solar evaporator. Following the conditions described in Example 1, a PPy-rGO-AuNPs conductive amplification layer and a 6-MAM / MOR dual-template PDA molecular imprint recognition layer were constructed sequentially to obtain a drug-responsive bamboo-based evaporation sensing unit. Six drug-responsive bamboo-based evaporation sensing units were interleaved and inserted into a 240mm diameter circular pearl cotton to form a six-unit bamboo-based evaporation monitoring array, which was then embedded in a lifebuoy-style floating substrate. Subsequently, an EIS impedance measurement module, a wireless communication module, a photovoltaic power supply module, a semi-circular acrylic cover, and a water storage tank were connected to produce a bamboo-based photothermal evaporation enrichment monitoring device.

[0048] The device obtained in this embodiment has an evaporation flux of 31 kg / m² under a single solar irradiation. Since the number of sensing units is less than that in Embodiment 1, the effective evaporation area and sampling representativeness are reduced. The stability of drug marker concentration gradient monitoring is R²=0.97, and the monitoring accuracy is 2 ng / L.

[0049] Example 5: The preparation method of the twelve-unit bamboo-based photothermal evaporation enrichment monitoring device in this embodiment includes the following steps: Choline chloride and oxalic acid (molar ratio 1:2) were placed in a beaker and stirred in a 50°C water bath for 45 min to prepare an acidic deep eutectic solution. Bamboo chips were then washed with water and air-dried at room temperature. 8 g of the bamboo chip precursor material was immersed in 450 mL of the acidic deep eutectic solution and heated in a 90°C water bath for 7 h. Subsequently, the mixture was washed with deionized water until neutral and dried in a 60°C oven to obtain lignin-free bamboo chips. 5g of lignin-free bamboo chips were soaked in 450mL of a 2g / L ZnO / water mixed solution for 0.8h. After being removed and air-dried, the chips were placed on a 250℃ heating platform for 40 seconds to obtain a bamboo-based solar evaporator. Following the conditions described in Example 1, a PPy-rGO-AuNPs conductive amplification layer and a 6-MAM / MOR dual-template PDA molecular imprint recognition layer were constructed sequentially to obtain a drug-responsive bamboo-based evaporation sensing unit. Twelve drug-responsive bamboo-based evaporation sensing units were interleaved and inserted into circular pearl cotton with a diameter of 240 mm to form a twelve-unit bamboo-based evaporation monitoring array, which was then embedded in a lifebuoy-type floating substrate. Subsequently, an EIS impedance measurement module, a wireless communication module, a photovoltaic power supply module, a semi-circular acrylic cover, and a water storage tank were connected to produce a bamboo-based photothermal evaporation enrichment monitoring device.

[0050] The device obtained in this embodiment has an evaporation flux of 30 kg / m² under a single solar irradiation. Due to the increased number of sensing units and the improved sampling coverage area, but the reduced array spacing, the stability of the drug marker concentration gradient monitoring is R²=0.98, and the monitoring accuracy is 2 ng / L.

[0051] Comparative Example 1: The preparation method of this comparative example differs from that of Example 1 in that the impregnation of the pyrrole / rGO / AuNPs aqueous solution and the FeCl3 oxidative polymerization steps are not performed, that is, the PPy-rGO-AuNPs conductive amplification layer is not constructed. The remaining steps are the same as those in Example 1.

[0052] Due to the lack of a conductive amplification layer, the charge transfer channel in this comparative example is unstable, making it difficult to distinguish changes in Rct caused by low concentrations of drug markers. Its evaporation flux is 32 kg / m², and the stability of drug marker concentration gradient monitoring decreases to R²=0.82, while the monitoring accuracy decreases to 20 ng / L.

[0053] Comparative Example 2: The preparation method of this comparative example differs from that of Example 1 in that only the PPy-rGO-AuNPs conductive amplification layer is constructed, and the 6-MAM / MOR dual-template PDA molecular imprint recognition layer is not constructed. The remaining steps are the same as those in Example 1.

[0054] This comparative example can maintain evaporation and conductivity, but lacks specific recognition pores and has a weak Rct response to changes in drug marker concentration; its evaporation flux is 33 kg / m², the stability of drug marker concentration gradient monitoring decreases to R²=0.58, and the monitoring accuracy is less than 50 ng / L.

[0055] Comparative Example 3: The preparation method of this comparative example differs from that of Example 1 in that: no 6-MAM and MOR template molecules are added when constructing the PDA layer to form a non-imprinted PDA layer, and the remaining steps are the same as in Example 1.

[0056] This comparative example lacks spatial cavities that match 6-MAM and MOR, and its selectivity and linear response are both lower than those of Example 1; its evaporation flux is 32 kg / m², the stability of drug marker concentration gradient monitoring decreases to R²=0.70, and the monitoring accuracy decreases to 25 ng / L.

[0057] Comparative Example 4: The preparation method of this comparative example differs from that of Example 1 in that only one drug-responsive bamboo-based evaporation sensing unit is used and embedded in a lifebuoy-type floating substrate, while the remaining steps are the same as in Example 1.

[0058] This comparative example can achieve single-point monitoring, but the effective evaporation area and water body sampling representativeness are insufficient; its device evaporation flux is 15 kg / m², the stability of drug marker concentration gradient monitoring decreases to R²=0.85, and the monitoring accuracy decreases to 10 ng / L.

[0059] Comparative Example 5: The preparation method of this comparative example differs from that of Example 1 in that: fifteen drug-responsive bamboo-based evaporation sensing units are inserted into a circular pearl cotton with a diameter of 240 mm to form an over-dense array, and the remaining steps are the same as in Example 1.

[0060] In this comparative example, the spacing between the sensing units was too small, affecting the dissipation of water vapor and the stability of the electrode connection; its evaporation flux decreased to 22 kg / m², the stability of drug marker concentration gradient monitoring decreased to R²=0.88, and the monitoring accuracy decreased to 10 ng / L.

[0061] like Figure 4 As shown, the device of Example 1 has an evaporation flux of 33 kg / m² under a single solar irradiation, which is significantly higher than 15 kg / m² of Comparative Example 4 and 22 kg / m² of Comparative Example 5, proving that the preferred nine-unit array can take into account both the effective evaporation area and the steam dissipation channel.

[0062] like Figure 5 As shown, in Example 1, ΔRct / Rct0 showed a good linear relationship with the concentration of drug markers (R²=0.99), which was significantly better than that of Comparative Example 1 (R²=0.82), Comparative Example 2 (R²=0.58) and Comparative Example 3 (R²=0.70). This demonstrates that the PPy-rGO-AuNPs conductive amplification layer and the 6-MAM / MOR dual-template PDA molecular imprint recognition layer are crucial for the stability of impedance monitoring.

[0063] like Figure 6 As shown, as the concentration of the drug marker increased from 1 ng / L to 50 ng / L, the semicircle diameter of the EIS Nyquist curve in Example 1 gradually increased, indicating that Rct increases with the increase of the target concentration.

[0064] like Figure 7 As shown, the number of sensing units affects both evaporation performance and monitoring stability. A nine-unit array has better sampling representativeness than a six-unit array, and better vapor dissipation and connection stability than a twelve-unit array, thus making it the preferred array structure of this invention.

[0065] Given that there are numerous embodiments of the present invention, and the raw materials and quantities involved can be selected within a limited range according to actual needs, and that the experimental data for each embodiment are extensive and numerous, it is not suitable to list and describe them one by one here. However, the content to be verified and the final conclusions obtained in each embodiment are similar. Therefore, the verification content of each embodiment will not be described one by one here.

[0066] The above description is merely a detailed explanation of preferred embodiments and principles of the present invention. For those skilled in the art, there may be changes in specific implementation methods based on the ideas provided by the present invention, and these changes should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a bamboo-based photothermal evaporation enrichment monitoring device, characterized in that, Includes the following steps: (1) After washing and drying the bamboo strips, soak them in an acidic deep eutectic solution and heat them at 80-100℃ for 5-8 hours. Then wash them until neutral and dry them to obtain lignin-free bamboo strips. Soak the lignin-free bamboo strips in a ZnO / water mixed solution for 0.5-1 hours, take them out and air dry them naturally. Then place them on a heating platform at 250-300℃ for 30-60 seconds to obtain a bamboo-based solar evaporator. (2) Immerse the bamboo-based solar evaporator in a pyrrole / rGO / AuNPs aqueous solution and add FeCl3 aqueous solution for oxidative polymerization for 0.5-2h to obtain a bamboo-based solar evaporator with a PPy-rGO-AuNPs conductive amplification layer; then place it in a Tris buffer containing 6-monoacetylmorphine 6-MAM, morphine MOR and dopamine for 1-6h, and then elute the 6-MAM and MOR template molecules to obtain a drug-responsive bamboo-based evaporation sensing unit with a 6-MAM / MOR dual template PDA molecular imprint recognition layer; (3) Several drug-responsive bamboo-based evaporation sensing units are interleaved and inserted into a circular pearl cotton to form a bamboo-based evaporation monitoring array, and the bamboo-based evaporation monitoring array is embedded in a ring-shaped floating substrate; (4) The bamboo-based evaporation monitoring array is integrated with the EIS impedance measurement module, wireless communication module, photovoltaic power supply module and condensate collection module to obtain the bamboo-based photothermal evaporation enrichment monitoring device.

2. The preparation method according to claim 1, characterized in that, In step (1), the acidic deep eutectic solution includes choline chloride and oxalic acid, and the molar ratio of choline chloride to oxalic acid is 1:(1-4).

3. The preparation method according to claim 1, characterized in that, In step (2), the concentration of pyrrole / rGO / AuNPs in the aqueous mixture is 0.05-0.20 mol / L, the concentration of rGO is 0.5-2.0 mg / mL, and the concentration of AuNPs (calculated as gold) is 0.1-1.0 mmol / L. The concentration of the FeCl3 aqueous solution is 0.05-0.20 mol / L.

4. The preparation method according to claim 1, characterized in that, In step (2), the pH of the Tris buffer is 8.0-8.8, the dopamine concentration is 1-5 mg / mL, the molar ratio of 6-MAM to MOR is 1:(0.5-2), and the molar ratio of the total template molecules of 6-MAM and MOR to dopamine is 1:(50-200).

5. The preparation method according to claim 1, characterized in that, In step (2), the elution solution for the template molecule is a mixture of ethanol / acetic acid or methanol / acetic acid with a volume ratio of 9:1, and the elution time is 0.5-2h.

6. The preparation method according to claim 1, characterized in that, In step (3), the number of drug-responsive bamboo-based evaporation sensing units is 3-12. The bamboo-based evaporation monitoring array is embedded in the inner ring of the ring-shaped floating substrate.

7. The preparation method according to claim 1, characterized in that, In step (4), the EIS impedance measurement module and the wireless communication module are located inside the ring-shaped floating substrate, and the photovoltaic power supply module is located on the surface of the ring-shaped floating substrate; the condensate collection module is located above the bamboo-based evaporation monitoring array.

8. A bamboo-based photothermal evaporation enrichment monitoring device prepared by the preparation method according to any one of claims 1-7.

9. The bamboo-based photothermal evaporation enrichment monitoring device according to claim 8, characterized in that, The evaporation flux under a single solar radiation exposure shall not be less than 30 kg / m².

10. The application of the bamboo-based photothermal evaporation enrichment monitoring device as described in claim 8 or 9 for watershed drug monitoring, characterized in that, It is used for in-situ evaporation enrichment of heroin-derived drug markers in water bodies, EIS impedance monitoring, and wireless early warning.

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