A composition for forming a plant interface gel in situ and a method of preparation

Abstract

This invention relates to a composition and preparation method for in-situ formation of plant interface gels. The composition, by weight, comprises 80-120 parts gelatin, 240-450 parts sodium L-pyrrolidone-5-carboxylate, 26-60 parts curdlan, and 280-460 parts pure water. It is prepared through a series of steps including static soaking, mixing and stirring, heating reaction, and in-situ curing at room temperature. The components synergistically form a three-dimensional interconnected network, with sodium L-pyrrolidone-5-carboxylate constructing ion conduction channels. The impedance response delay after watering is only 30 minutes, and the plants remain stable for 30 days after application. This composition does not damage the tree, has good biocompatibility, and a simple process, solving the problems of response delay and signal obstruction in existing monitoring schemes. It is suitable for real-time monitoring of plant moisture in precision irrigation.

Description

Technical Field

[0001] This invention relates to the field of biomaterials technology, specifically to a composition and preparation method for in situ forming plant interface gels. Background Technology

[0002] In the field of precision irrigation, real-time and accurate monitoring of plant water status is a core technological requirement. Existing monitoring solutions are mainly based on the principle of electrochemical impedance, but they generally suffer from technical defects such as response delay, signal transmission obstruction, risk of tree damage, and insufficient long-term stability.

[0003] Most mainstream solutions employ leaf impedance measurement, but this relies on water transport from the soil through the roots and stems to the leaves to reflect the tree's internal water content. The long transmission path results in significant response delays, failing to meet real-time control requirements. Another solution uses bark impedance measurement; however, the bark, as a natural interface barrier, significantly hinders electrical signal transmission, making it difficult to accurately and quickly respond to changes in internal tree water content, thus limiting monitoring accuracy. To improve signal transmission efficiency, some solutions attempt to remove local bark or outer tissue and directly attach conductive elements such as metal electrodes. While this improves signal sensitivity to some extent, it damages the cambium and protective layers, increasing the risk of disease infection and affecting long-term plant health, making long-term stable monitoring impossible. Furthermore, the lack of stable ion pathways between existing electrodes and the tree interface leads to poor electrical signal transmission stability, further exacerbating data fluctuations during long-term monitoring.

[0004] In summary, existing technologies have failed to construct a low-latency, low-impedance, stable and reliable signal transmission interface without damaging the tree, making it difficult to achieve real-time and accurate monitoring of the tree trunk's moisture status. This technological bottleneck has become a key factor restricting the development of precision irrigation technology. Therefore, developing a plant interface signal transmission scheme that can balance tree safety, signal transmission stability, and real-time monitoring is of great practical significance and research necessity. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides a composition and preparation method for in-situ formation of plant interface gels.

[0006] To achieve the above objectives, this application employs the following technical solution: This application provides a composition for in-situ formation of plant interface gels, comprising, by weight, the following components: 80 to 120 parts gelatin; 240 to 450 parts of sodium L-pyrrolidone-5-carboxylate; 26 to 60 parts of kerogen gum; 280 to 460 parts pure water.

[0007] Based on the above technical solution, the gelatin molecular chain is rich in hydrophilic groups such as hydroxyl and amino groups, which can strongly interact with the carboxyl and lactam rings in the L-pyrrolidone-5-carboxylate molecule through ionic and hydrogen bonding interactions. The hydroxyl groups in the gelatin molecular chain participate in multi-point hydrogen bonding association, and its acyl groups tend to form hydrophobic interactions, thus providing stable physical interaction units in the system. These multiple non-covalent interactions synergistically enable the components to form a continuous and stable molecular cooperative system in a pure aqueous dispersion environment. Simultaneously, the zwitterionic properties of L-pyrrolidone-5-carboxylate allow it to migrate effectively in the continuous ionic conduction environment constructed by gelatin, thereby endowing the system with excellent ionic conductivity.

[0008] As a further improvement of this application, the gelatin has a gel strength of 200-300 Bloom and a molecular weight of 10,000-50,000 Da. This molecular weight and gel strength range ensure that the gelatin fully absorbs water and swells during the wetting stage, with a moderate degree of molecular chain extension. This allows it to form stable entanglements and cross-links with other components without causing excessively high solution viscosity due to excessively long molecular chains, or insufficient mechanical support due to excessively short molecular chains.

[0009] As a further improvement of this application, the purity of the L-pyrrolidone-5-carboxylate sodium is ≥98%, and the moisture content is ≤0.5wt%. High purity can avoid impurity ions interfering with its intermolecular interaction with gelatin and guar gum, and prevent impurities from occupying cross-linking sites and causing defects in the gel network structure; low moisture content can ensure that its actual effective content in the formulation is stable, and avoid the impact of moisture fluctuations on the construction efficiency of ion conduction channels.

[0010] As a further improvement of this application, the gellan gum is a high-acyl gellan gum with an acyl content of 10-15 wt%. This acyl content range allows the gellan gum molecular chains to form moderate hydrophobic aggregations during the heating stage, generating uniformly distributed physical cross-linking points. These cross-linking points are precisely interwoven with the ionic bond network of gelatin-L-pyrrolidone-5-carboxylate sodium, constructing a high-strength, high-toughness gel network. If the acyl content is too high, it will lead to over-crosslinking and the gel will become brittle; if it is too low, it will lead to insufficient crosslinking and the gel will be easily deformed.

[0011] As a further improvement of this application, the resistivity of the pure water is 18.3 MΩ•cm. Using pure water can avoid interference from metal ions and impurity ions in the water with the intermolecular interactions of the components, prevent impurity ions from occupying ion conduction channels, and avoid affecting the conductivity of the gel. At the same time, the pH value of pure water is 7, which can avoid the hydrolytic degradation of gelatin molecular chains by acidic or alkaline environments, protect the active groups such as amino and hydroxyl groups of gelatin, and ensure the smooth progress of the cross-linking reaction.

[0012] To achieve the above objectives, this application also provides a method for preparing a plant-based interfacial gel, comprising the following steps: S1. By weight, add 80 to 120 parts of gelatin to the reaction vessel, then add 240 to 450 parts of sodium L-pyrrolidone-5-carboxylate, and let it stand at 20 to 30°C for 0.5 to 1.5 hours to allow the gelatin to fully absorb water and swell. S2. Add 26 to 60 parts of gellan gum and 280 to 460 parts of pure water to the reaction vessel of step S1, and stir at a stirring speed of 200 to 400 rpm for 15 to 30 minutes to mix the materials evenly and obtain a mixed solution. S3. Heat the mixed solution obtained in step S2 to 60℃~70℃, and stir continuously at a stirring speed of 250~350rpm for 30~60min until a uniform prepolymer gel precursor is formed. S4. Apply the prepolymerized gel precursor to a preset area of ​​the target substrate, the preset area being the designated location where the gel structure is to be formed, and cure in situ for 1-3 minutes at room temperature of 20-40℃ to obtain a plant interface gel.

[0013] Based on the above technical solution, gelatin, as a hydrolyzed product of collagen, contains a large number of hydrophilic groups such as hydroxyl and amino groups in its molecular chain. During the static soaking stage at 20-30℃, it comes into full contact with sodium L-pyrrolidone-5-carboxylate and pure water, absorbing water and swelling through hydrogen bonding. Sodium L-pyrrolidone-5-carboxylate, as a water-soluble zwitterionic compound, accelerates the swelling of gelatin through ion penetration, and strengthens the gel network by forming ionic bonds between the carboxyl groups and the amino groups of gelatin, and hydrogen bonds between the lactam ring and the hydroxyl groups of gelatin. At the same time, it constructs ion conduction channels by virtue of its zwitterionic properties to meet the conductivity requirements, and also improves the flowability of the prepolymerized gel precursor, facilitating subsequent application. During the heating stage at 60-70℃, the molecular chain of gelatin expands, with hydroxyl groups participating in hydrogen bond formation and acyl groups polymerizing through hydrophobic interactions. The gel forms physical cross-linking points, intertwining with the ionic bond network of gelatin and sodium L-pyrrolidone-5-carboxylate, significantly improving the mechanical properties of the gel without the need for additional chemical cross-linking agents, thus enhancing biocompatibility. Pure water serves as the dispersion medium, providing a clean environment for the intermolecular interactions of each component and preventing impurity ions from interfering with conductivity and reaction stability. During the 1-3 minute in-situ curing stage at room temperature, the slow evaporation of water promotes the shrinkage and densification of the gel network, achieving rapid molding. The components are formulated in a ratio of 80-120 parts gelatin, 240-450 parts sodium L-pyrrolidone-5-carboxylate, 26-60 parts guar gum, and 280-460 parts pure water, combined with specific process parameters, ultimately forming a uniform, electrically stable, mechanically excellent, and biocompatible plant interface gel.

[0014] As a further improvement of this application, in step S3, the viscosity of the prepolymerized gel precursor at 25°C is 500–2000 mPa•s. This viscosity range is determined by the ratio of each component and the degree of cross-linking at elevated temperature. The molecular entanglement of gelatin and the initial cross-linking of guar gum are the core factors for adjusting the viscosity. A suitable viscosity ensures that the prepolymerized gel precursor has fluidity when applied without sagging due to excessively low viscosity.

[0015] As a further improvement of this application, in step S3, the heating rate is 2-5℃ / min. Slow and uniform heating can avoid local overheating that could lead to gelatin molecular chain degradation and excessive cross-linking of gelatin, ensuring that all components undergo intermolecular interactions simultaneously during the heating process to form a uniform gel network; if the heating is too fast, defects such as excessively high local cross-linking density and the formation of bubbles inside the gel may occur.

[0016] As a further improvement of this application, in step S4, the application method is drop coating or coating. Preferably, the drop coating uses a quantitative dropper with a dropping rate of 0.5-2 mL / min and a single drop volume of 0.05-0.1 mL; the coating uses a doctor blade with a doctor blade gap of 50-200 μm and a coating speed of 5-15 cm / s.

[0017] As a further improvement to this application, in step S4, the target substrate may be a plant trunk, plant branch, plant stem, plant root system, plant leaf, etc.

[0018] The beneficial effects of this application are as follows: 1. By using a specific ratio and synergistic effect of gelatin, sodium L-pyrrolidone-5-carboxylate, guar gum and pure water, a three-dimensional interconnected gel network is formed. Sodium L-pyrrolidone-5-carboxylate constructs a highly efficient ion conduction channel with excellent signal transmission efficiency, solving the problem of signal transmission obstruction in existing solutions.

[0019] 2. The plant interface gel can be applied to the tree trunk without damaging the tree. After watering, the impedance response delay is only 30 minutes, which can provide real-time and accurate feedback on the plant's water status, breaking through the technical bottleneck of response delay in traditional monitoring solutions.

[0020] 3. The cross-linked network formed by guar gum and gelatin can stably adhere to the plant interface. The experimental group of plants still survived after 30 days, which significantly improved the stability of long-term monitoring and avoided the defects of existing methods such as tree damage and easy failure.

[0021] 4. The preparation process requires no additional chemical cross-linking agents, the components have good biocompatibility, the process is simple, it can be cured quickly at room temperature, the application method is flexible, and it has both safety and practicality, providing an efficient and reliable interface solution for plant water monitoring in the field of precision irrigation. Attached Figure Description

[0022] Figure 1 These are the Nyquist plots corresponding to Example 3 and Comparative Example 1; Figure 2 This is an analysis diagram of the sensitivity test of the plant interface gel reaction in Example 3; Figure 3 These are photos of plants 30 days after using the plant interface gel of Example 3. Detailed Implementation

[0023] The technical solution of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0024] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to specific embodiments.

[0025] Example 1 By weight, 80 parts of gelatin with a gel strength of 200 Bloom and a molecular weight of 10000 Da, 240 parts of sodium L-pyrrolidone-5-carboxylate with a purity ≥98% and a moisture content ≤0.5wt%, 26 parts of high-acyl curdlan gum with an acyl content of 10wt%, and 280 parts of pure water with a resistivity of 18.3 MΩ•cm and a pH of 7.0 were selected. In preparation, gelatin and sodium L-pyrrolidone-5-carboxylate were first added to a reaction vessel and allowed to stand at 20℃ for 0.5 h to allow the gelatin to fully absorb water and swell. Then, curdlan gum was added. Mix the mixture with pure water at a stirring speed of 200 rpm for 15 min to obtain a mixed solution. Then, heat the mixed solution to 60°C at a heating rate of 2°C / min and continue stirring at 250 rpm for 30 min at this temperature to form a uniform prepolymer gel precursor with a viscosity of 500 mPa•s at 25°C. Apply the prepolymer gel precursor to a preset area of ​​the target substrate by drop coating and cure in situ at room temperature of 20°C for 1 min to obtain the plant interface gel.

[0026] Example 2 By weight, 120 parts of gelatin with a gel strength of 300 Bloom and a molecular weight of 50,000 Da, 450 parts of sodium L-pyrrolidone-5-carboxylate with a purity ≥98% and a moisture content ≤0.5wt%, 60 parts of high-acyl currant with an acyl content of 15wt%, and 460 parts of pure water with a resistivity of 18.3 MΩ•cm and a pH of 7.0 were selected. In preparation, gelatin and sodium L-pyrrolidone-5-carboxylate were first added to a reaction vessel and allowed to stand at 30℃ for 1.5 hours to allow the gelatin to fully absorb water and swell. Then, currant was added. Mix the mixture with pure water and stir at 400 rpm for 30 min to obtain a mixed solution. Then, heat the mixed solution to 70°C at a heating rate of 5°C / min and continue stirring at 350 rpm for 60 min at this temperature to form a uniform prepolymer gel precursor with a viscosity of 2000 mPa•s at 25°C. Apply the prepolymer gel precursor to a preset area of ​​the target substrate by coating and cure in situ at 40°C for 3 min to obtain the plant interface gel.

[0027] Example 3 By weight, 100 parts of gelatin with a gel strength of 250 Bloom and a molecular weight of 30,000 Da, 320 parts of sodium L-pyrrolidone-5-carboxylate with a purity ≥98% and a moisture content ≤0.5wt%, 42 parts of high-acyl curdlan gum with an acyl content of 12wt%, and 350 parts of pure water with a resistivity of 18.3 MΩ•cm and a pH of 7.0 were selected. In preparation, gelatin and sodium L-pyrrolidone-5-carboxylate were first added to a reaction vessel and allowed to stand at 25°C for 1.0 h to allow the gelatin to fully absorb water and swell. Then, curdlan gum was added. Mix the mixture with pure water and stir at 300 rpm for 22 min to obtain a mixed solution. Then, heat the mixed solution to 65°C at a heating rate of 3°C / min and continue stirring at 300 rpm for 45 min at this temperature to form a uniform prepolymer gel precursor with a viscosity of 1200 mPa•s at 25°C. Apply the prepolymer gel precursor to a preset area of ​​the target substrate by coating and cure in situ at 30°C for 2 min to obtain the plant interface gel.

[0028] Comparative Example 1 Based on mass fractions, gels with the same specifications as in Example 3 and a gel strength of 250 were selected. The preparation consisted of 100 parts of gelatin with a molecular weight of 30,000 Da, 320 parts of sodium L-pyrrolidone-5-carboxylate with a purity ≥98% and a moisture content ≤0.5wt%, and 350 parts of pure water with a conductivity ≤500μS / cm and a pH of 7.0. In the preparation process, gelatin and sodium L-pyrrolidone-5-carboxylate were first added to a reaction vessel and allowed to stand at 25°C for 1.0 h to allow the gelatin to fully absorb water and swell. Then, all the pure water was added, and the mixture was stirred at 300 rpm for 22 min to obtain a mixed solution. Subsequently, the mixed solution was heated to 65°C at a heating rate of 3°C / min, and stirred continuously at 300 rpm for 45 min at this temperature to form a prepolymer gel precursor with a viscosity of 350 mPa•s at 25°C. This prepolymer gel precursor was applied to a predetermined area of ​​the target substrate using a coating method. After being placed at room temperature of 30°C for 2 min, it was cured in situ to obtain a plant interface gel without kerogen.

[0029] 1. Electrochemical impedance spectroscopy (EIS) was performed on the plant interface gels prepared in Example 3 and Comparative Example 1. The testing steps are as follows: Healthy trees (such as poplars) with uniform growth and a trunk diameter of 8-10 cm were selected as target substrates and divided into experimental and control groups. A flat, undamaged area free of pests and diseases was selected 50 cm above the ground as a pre-defined area. Two small peeling holes, approximately 5 mm in diameter and 2 cm apart, were made in this pre-defined area to expose the cambium or xylem tissue of the tree. Prepolymer gel precursors prepared in Example 3 and Comparative Example 1 were applied. Example 3 was applied to the two corresponding wound locations on the poplar trees in the experimental group, and Comparative Example 1 was applied to the two corresponding wound locations on the poplar trees in the control group, ensuring the test... The samples were bubble-free and defect-free, and cured in situ to form plant interface gels. Two sets of two-electrode systems were used, corresponding to Example 3 and Comparative Example 1, respectively. Platinum sheets with a purity of 99.99% were selected for the electrode assembly. The two working electrodes of the electrode assembly were placed parallel to each other and tightly attached to the surface of the plant interface gel. The electrode assembly holding the plant interface gel was then fixed in an insulating test fixture and placed in a constant temperature and humidity environment of 25°C and 50% relative humidity for 15 minutes to allow the plant interface gel-electrode interface to reach a stable state. The electrochemical workstation was then connected, and the test parameters were set: frequency range of 10... -2 ~10 5A sinusoidal AC disturbance signal with an amplitude of 10mV was applied at Hz. The test mode was AC impedance testing at open circuit potential. The test program was started, and the system was kept free from external vibration and electromagnetic interference during the test. After the test, the electrochemical workstation automatically recorded the real part Z′ and imaginary part Z′′ of the impedance at different frequencies and directly generated a Nyquist plot with Z′ as the abscissa and Z′′ as the ordinate. Finally, the original data was imported using ZView impedance analysis software, and an equivalent circuit was fitted based on the ion conduction characteristics of the plant interface gel to extract key parameters such as charge transfer resistance and interfacial contact resistance. To ensure data reliability, the above test was repeated 3 times, and the average data of the 3 tests was used to plot the final Nyquist plot. Figure 1 As shown, Figure 1 In the diagram: The intersection of the EIS curve and the real part Z′ of the horizontal axis in the coordinate system is the semicircular impedance value Z. Figure 1 In the text, C-PG represents Example 3, and GP represents Comparative Example 1. Figure 1 It is evident that the plant interface gel prepared by the technical solution of this application has a lower semicircular impedance value, which will inevitably result in superior signal transmission performance.

[0030] 2. Reactivity sensitivity test of the plant interface gel prepared in Example 3 Healthy plants (such as poplars) with uniform growth and a trunk diameter of 8-10cm were selected as the target substrate. A flat area free from damage and pests was selected 50cm above the ground on the trunk as the preset area. Two small peeling holes with a diameter of about 5mm were made in the preset area, with a center-to-center distance of about 2cm between the two holes, to expose the cambium or xylem living tissue of the tree. The prepolymer gel precursor prepared in Example 3 was taken and the sample was cured in situ at the two wound locations, ensuring that there were no air bubbles or defects, to form plant interface gels.

[0031] The electrode assembly was made of 99.99% pure platinum sheets. The two working electrodes of the assembly were placed parallel to each other and tightly against the surface of the plant interface gel, ensuring effective contact between the electrodes and the gel. The electrode assembly, holding the plant interface gel, was then fixed in an insulating test fixture and placed in a constant temperature and humidity environment of 25℃ and 50% relative humidity for 15 minutes to allow the plant interface gel-electrode interface to stabilize. The assembly was then connected to an electrochemical workstation, and the test parameters were set as follows: frequency range 10... -2 ~10 5 The test mode was AC impedance testing under open-circuit potential, with a sinusoidal AC voltage amplitude of 10mV and a frequency of Hz. Tree impedance spectrum data were monitored sequentially before and after three watering intervals, and the time-series tree impedance spectrum data were recorded. The ratio of the time-series tree impedance spectrum data to the impedance value Z0 of the completely dehydrated semicircle of the same tree species was calculated and recorded as the normalized impedance. The normalized impedance was then sorted according to time sequence, and a curve of normalized impedance changing with time was plotted, as shown below. Figure 2As shown, Figure 2 This is an analysis chart of the sensitivity test of the plant interface gel reaction in Example 3, which shows the delay time for a significant change in normalized impedance after watering. Figure 2 The time from the peak to the trough (the location of the dashed box) is 30 minutes, which means the time from the peak to the trough is 30 minutes.

[0032] It should be noted that the impedance value Z0 of the completely dehydrated semicircle in this embodiment is obtained from historical data, which is obtained by taking the average value of multiple sets of tree impedance spectrum data of healthy trees of the same variety under completely dehydrated conditions.

[0033] For example, select healthy trees (such as poplars) with uniform growth and a trunk diameter of 8-10cm as the target substrate. Select a flat, undamaged area free of pests and diseases at 50cm above the ground as the pre-defined area. Make two small peeling holes (approximately 5mm in diameter) with a center-to-center distance of about 2cm in this pre-defined area to expose the cambium or living xylem tissue of the tree. Apply the prepared prepolymer gel precursor to the corresponding two wound locations on the poplar tree, ensuring the sample is free of bubbles and defects. Allow it to solidify in situ to form an interface gel device. Use a two-electrode system, selecting platinum sheets with a purity of 99.99% for the electrode assembly. Place the two working electrodes of the electrode assembly parallel to each other and tightly against the surface of the interface gel device, ensuring effective contact between the electrodes and the device. Then, fix the electrode assembly holding the interface gel device in an insulating test fixture and place it in a constant temperature and humidity environment of 25℃ and 50% relative humidity for 15 minutes to allow the interface gel device-electrode interface to stabilize. Connect to an electrochemical workstation and set the test parameters: frequency range 10... -2 ~10 5 A sinusoidal AC disturbance signal with an amplitude of 10mV was applied at Hz, and the test mode was AC impedance testing under open circuit potential. When the healthy plant was in a completely dehydrated state, the test program was started. During the test, the system was kept free from external vibration and electromagnetic interference. After the test, the electrochemical workstation automatically recorded the real part Z′ and imaginary part Z′′ of the impedance at different frequencies and directly generated a Nyquist plot with Z′ as the abscissa and Z′′ as the ordinate. Finally, the original data was imported using ZView impedance analysis software, and the equivalent circuit was fitted by combining the ion conduction characteristics of the interface gel device to extract key parameters such as charge transfer resistance and interface contact resistance. To ensure data reliability, the above test was repeated 3 times, and the average data of the 3 tests was used to plot the final Nyquist plot. The intersection of the EIS curve and the real part Z′ of the horizontal axis in the Nyquist plot is the semicircular impedance value, which is the calibration history data corresponding to the semicircular impedance value Z0 of the completely dehydrated healthy plant.

[0034] 3. Lifetime test of the plant interface gels prepared in Example 3 and Comparative Example 1 Six healthy poplar trees with uniform growth (no significant differences in height, crown width, and trunk thickness) and a trunk diameter of 8-10 cm were selected and randomly divided into two groups (3 trees in each group, i.e., 3 parallel samples), labeled as the experimental group (corresponding to the plant interface gel in Example 3) and the control group (corresponding to the plant interface gel in Example 1). For each tree, a flat area free from damage and pests / diseases was selected at 50 cm above the ground as the pre-defined area. Two small peeling holes with a diameter of approximately 5 mm were made in the pre-defined area. The spacing between the centers was approximately 2 cm to expose the cambium or living xylem tissue of the tree. The prepolymerized gel precursor prepared in Example 3 was applied to the wound sites of the three plants in the experimental group, ensuring the samples were free of bubbles and defects, and cured in situ to form a plant interface gel. Simultaneously, the prepolymerized gel precursor prepared in Comparative Example 1 was applied to the wound sites of the three plants in the control group using the same method, ensuring the samples were free of bubbles and defects, and cured in situ to form a plant interface gel. The application and in-situ curing conditions were kept completely consistent between the two groups. A lifetime monitoring program was then initiated, and the appearance of the plant interface gel was observed periodically (whether it cracked, peeled off, weathered, or became moldy). Verification showed that the three plants in the experimental group remained viable after 30 days. Figure 3 This is a photo of one of the plants in the experimental group 30 days later; the three plants in the control group withered after 10 days.

[0035] In summary, the technical solution of this application demonstrates significant effectiveness. The plant interface gel prepared through specific components and processes exhibits excellent performance in conductivity, responsiveness, and lifespan. Electrochemical impedance spectroscopy (EIS) tests show that the plant interface gel of Example 3 (containing gluconolactone) has lower impedance, superior charge transfer and interfacial contact performance, and outstanding signal transmission efficiency compared to Comparative Example 1 (without gluconolactone). In the responsiveness test, after the plant interface gel was applied to the tree trunk, the impedance change was only delayed by 30 minutes, demonstrating rapid response to changes in plant moisture status and meeting real-time monitoring requirements. Lifespan tests show that the plants in the experimental group (plant interface gel of Example 3) survived for 30 days without cracking or peeling, while the plants in the control group (plant interface gel of Comparative Example 1) withered after 10 days, highlighting the crucial role of gluconolactone in the stability and biocompatibility of the gel network.

[0036] In addition, the preparation of plant interface gels does not require additional chemical cross-linking agents, has high biosafety, and does not damage the tree when applied. It solves the pain points of existing technologies such as response delay, signal blockage, tree damage, and insufficient stability, and provides a reliable interface transmission solution for real-time monitoring of plant moisture in precision irrigation.

[0037] Although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0038] The detailed descriptions listed above are merely specific descriptions of feasible implementation methods of this application and are not intended to limit the scope of protection of this application. All equivalent implementation methods or modifications made without departing from the spirit of the art of this application should be included within the scope of protection of this application.

Claims

1. A composition for in-situ formation of plant interfacial gels, characterized in that, Based on parts by weight, it includes the following components: 80 to 120 parts gelatin; 240 to 450 parts of sodium L-pyrrolidone-5-carboxylate; 26 to 60 parts of kerogen gum; 280 to 460 parts pure water.

2. The composition for in-situ formation of plant interface gels according to claim 1, characterized in that, The gel strength of the gelatin is 200-300 Bloom, and the molecular weight is 10,000-50,000 Da.

3. The composition for in-situ formation of plant interface gels according to claim 1, characterized in that, The purity of the L-pyrrolidone-5-carboxylic acid sodium salt is ≥98%, and the moisture content is ≤0.5wt%.

4. The composition for in-situ formation of plant interface gels according to claim 1, characterized in that, The kelden gum is a high-acyl kelden gum with an acyl content of 10-15 wt%.

5. The composition for in-situ formation of plant interface gels according to claim 1, characterized in that, The resistivity of the pure water is 18.3 MΩ•cm.

6. A method for preparing a plant-based interfacial gel, characterized in that, Includes the following steps: S1. By weight, add 80 to 120 parts of gelatin to the reaction vessel, then add 240 to 450 parts of sodium L-pyrrolidone-5-carboxylate, and let it stand at 20 to 30°C for 0.5 to 1.5 hours to allow the gelatin to fully absorb water and swell. S2. Add 26 to 60 parts of gellan gum and 280 to 460 parts of pure water to the reaction vessel of step S1, and stir at a stirring speed of 200 to 400 rpm for 15 to 30 minutes to mix the materials evenly and obtain a mixed solution. S3. Heat the mixed solution obtained in step S2 to 60℃~70℃, and stir continuously at a stirring speed of 250~350rpm for 30~60min until a uniform prepolymer gel precursor is formed. S4. Apply the prepolymerized gel precursor to a preset area of ​​the target substrate, the preset area being the designated location where the gel structure is to be formed, and cure in situ for 1-3 minutes at room temperature of 20-40℃ to obtain a plant interface gel.

7. The method for preparing plant interface gel according to claim 6, characterized in that, In step S3, at 25°C, the viscosity of the prepolymerized gel precursor is 500–2000 mPa•s.

8. The method for preparing plant interface gel according to claim 6, characterized in that, In step S3, the heating rate is 2–5 °C / min.

9. The method for preparing plant interface gel according to claim 6, characterized in that, In step S4, the application method is drop coating or coating.

10. The method for preparing plant interface gel according to claim 6, characterized in that, In step S4, the target substrate is any one of the following: plant trunk, plant branch, plant stem, plant root system, and plant leaf.

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