Preparation method of culture medium and modified porous calcium titanate flaky carrier

Abstract

The preparation method of the culture medium comprises the following steps: preparing a composite culture solution; immersing the modified porous calcium titanate flaky carrier into the composite culture solution, and standing until the carrier adsorbs nutrients to be saturated; after soaking, taking out the nutrient-loaded carrier and naturally airing; the preparation method comprises the following steps: dissolving silk fibroin in deionized water to form a solution, adding glacial acetic acid into the solution, mechanically stirring, and standing to obtain a silk fibroin slow-release solution; and brushing the surface of the obtained nutrient-loaded carrier with the prepared silk fibroin slow-release solution to finally prepare the calcium titanate-based slow-release culture medium attached with the silk fibroin film. The invention also provides a preparation method of the modified porous calcium titanate flaky carrier. The calcium titanate-based periphyton slow-release culture medium is adopted in the culture medium, a modified calcium titanate adsorption carrier sheet is soaked in a culture solution, silk fibroin is brushed on the surface of a carrier, so that a slow-release film with a net structure is formed, and organic carbon and nutrient elements are provided for growth of periphyton.

Description

[0001] The present invention is a divisional application of application number: 2024103113081, patent application date: 2024-03-19, and invention name: "A device for in situ cultivation and collection of peripheral organisms on an artificial matrix and a method for preparing a culture matrix and a modified porous calcium titanate sheet carrier." Technical Field

[0002] The invention relates to the technical field of biological culture, in particular to a device for in-situ culture and collection of surrounding organisms on an artificial matrix, and a method for preparing a culture matrix and a modified porous calcium titanate sheet carrier. Background Art

[0003] Periclastic organisms are commonly found on the surface of various substrates in wetlands and are important biological indicators of the health of wetland ecosystems. At present, most of the research on periiclastic organisms at home and abroad is mainly based on closed laboratory cultivation and collection, focusing on the effects of different environmental factors (light, pH, water flow rate, substrate, etc.) on the community structure of periiclastic organisms, as well as the mechanism of periiclastic organisms in removing pollutants from water and soil.

[0004] Since most periphyton in the natural environment exist at the water-soil interface and there are many influencing factors in the environment, it is difficult to simulate the growth conditions of periphyton in the laboratory, so laboratory culture has the characteristics of few species and low richness. Therefore, periphyton cultivated in artificially simulated natural environment cannot completely replace the periphyton grown naturally in the in situ environment. Periphyton in the natural environment can be divided into periphyton attached to rocks, periphyton attached to trees, and periphyton attached to plants. When using tools to collect natural periphyton samples, due to the high degree of adhesion between periphyton and the surface of natural matrix and its common presence in water, the biomass that can be collected is often small and the collection is unstable, so it is difficult to collect using tools alone.

[0005] At present, there are devices for in-situ cultivation of periphyton in natural environments. The interior of the devices is an artificial matrix for cultivating periphyton, and the exterior is mostly a box structure, which can provide growth space for periphyton and exchange water, nutrients and other substances with the external environment, so as to achieve enrichment and cultivation of periphyton grown under natural environment conditions. However, during the cultivation process, particles such as water sediment or other impurities will enter and precipitate in the in-situ cultivation device, resulting in the cultured periphyton often being difficult to collect completely and having many attached impurities, which ultimately affects the subsequent research and application of periphyton.

[0006] In addition, the current culture matrix of Zhou Cong organisms also has the following shortcomings. First, the materials used are not environmentally friendly and will produce toxic and harmful substances after long-term use, or the natural materials used are easily degraded, resulting in a relatively short service life; second, some materials with relatively small specific surface areas have a single structure of the cultured Zhou Cong organism community and are unstable in nature, which can easily cause shedding, resulting in low biomass and weak activity of Zhou Cong organisms, which cannot meet the research and application needs of Zhou Cong organisms; third, the culture matrix cannot provide sufficient and long-term nutrients for Zhou Cong organisms, cannot form a stable and multifunctional microbial community, and cannot form a steady-state micro-ecosystem. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention provides a device for in-situ cultivation and collection of periphyton on an artificial matrix, a culture matrix and a preparation method of a modified porous calcium titanate sheet carrier, which overcomes the shortcomings of the prior art, realizes automatic energy supply through solar panels to provide electricity for a water pump, and then the water pump can maintain a fixed flow rate of water for the growth of periphyton, and the collector body is detachable to facilitate the collection of growing periphyton, thereby effectively realizing the two functions of in-situ cultivation and collection. And by using the modified calcium titanate adsorption carrier sheet as a loading matrix material and modifying it with barium ferrite magnetic powder, a magnetic field is formed to strengthen the initial adsorption of periphyton bacteria on the surface of calcium titanate, so as to facilitate the subsequent stable growth of biofilm; and by brushing silk fibroin on the carrier surface, organic carbon and nutrient elements are continuously provided for the growth of periphyton on the carrier.

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0009] A device for in-situ culture and collection of peripheral organisms on an artificial matrix, comprising a collector body, a placement slot is provided on the front side of the collector body, detachable enclosures are embedded on the left and right sides of the placement slot, a culture matrix is ​​installed in the placement slot, a buffer grille is provided on the outside of the culture matrix, and both ends of the buffer grille are clamped on the inner side of the detachable enclosure;

[0010] A protective cover is installed on the rear side of the collector body, and a water pump is installed inside the protective cover. The water inlet end of the water pump is connected to one end of the water inlet pipe, and the other end of the water inlet pipe passes through the protective cover and the collector body in sequence and is communicated with the inner cavity of the placement slot; the water outlet end of the water pump is connected to one end of the water outlet pipe, and the other end of the water outlet pipe extends to the outside of the protective cover.

[0011] Preferably, a solar panel is installed above the protective cover, and the solar panel is connected to the water pump via a power supply circuit.

[0012] Preferably, a pH meter is also installed in the protective cover, and the detection probe of the pH meter passes through the protective cover and the collector body in sequence and is located in the inner cavity of the placement slot, so as to detect the pH index of the water quality in the placement slot.

[0013] Preferably, the detection probe of the pH meter is higher than the water inlet pipeline.

[0014] Preferably, the inner walls on the left and right sides of the placement slot are provided with engaging grooves, and the removable enclosure is inserted into the engaging grooves; the inner wall of the removable enclosure is provided with limiting grooves, and the two ends of the buffer grille are fixedly clamped in the limiting grooves.

[0015] Preferably, the water inlet pipeline includes a main water inlet pipe and multiple water inlet branches, one end of the main water inlet pipe is connected to the water inlet end of the water pump, the other end of the main water inlet pipe is connected to one end of each water inlet branch pipe through a connecting pipe, the other end of each water inlet branch pipe is evenly arranged along the horizontal axis of the collector body and is connected to the inner cavity of the placement slot, and each water inlet branch pipe is arranged perpendicular to the culture matrix and is separated from the culture matrix by a distance.

[0016] Preferably, at least two supporting columns are respectively installed under the collector body and under the protective cover.

[0017] Preferably, the support column includes a fixed column and an adjusting column, the upper ends of the fixed column are respectively fixed at the bottom of the collector body and the bottom of the protective cover, the lower end face of the fixed column is provided with an adjustment hole along the axial direction, the upper end of the adjusting column is inserted into the mounting hole, the side surface of the fixed column is provided with a plurality of outer holes evenly along the axial direction, the side surface of the adjusting column is provided with a plurality of inner holes evenly along the axial direction, the outer holes correspond to the inner holes, a thread is provided in the inner hole, the screw passes through the outer hole and the inner hole in turn and is connected and fixed to the inner hole through the thread.

[0018] Preferably, the collector body and the detachable enclosure are both made of stainless steel; and the buffer grille is made of polyvinyl chloride.

[0019] Preferably, the culture matrix is ​​a calcium titanate-based sustained-release culture matrix, and its preparation method comprises the following steps:

[0020] Step S1: preparing a composite culture solution, wherein the components and concentrations contained in the composite culture solution are: glucose: 360 mg / L, sodium lactate: 3.50 g / L, NH4Cl: 1.00 g / L, K2HPO4: 0.50 g / L, MgCl2·6H2O: 0.04 g / L, CaCl2·2H2O: 0.04 g / L, Na2SO4: 1.50 g / L;

[0021] Step S2: immersing the modified porous calcium titanate sheet carrier in the composite culture solution and leaving it to stand at 25° C. until the carrier is saturated with nutrients; after the immersion is completed, taking out the nutrient-loaded carrier and drying it naturally;

[0022] Step S3: dissolving 15-25 g of silk fibroin in 1.5-2.5 L of deionized water, stirring at 80° C. for 40-50 minutes to form a solution, adding 2% glacial acetic acid to the solution, and continuing to mechanically stir at 300 rpm for 40-50 minutes to obtain a silk fibroin sustained-release solution;

[0023] Step S4: evenly apply the silk fibroin sustained-release solution obtained in step S3 to the surface of the nutrient-loaded carrier obtained in step S2, and dry it at 40°C; repeat the application and drying steps 3-5 times to finally obtain a calcium titanate-based sustained-release culture matrix with a 100-200 μm thick silk fibroin film attached.

[0024] Preferably, in step S2, the method for preparing the modified porous calcium titanate sheet carrier comprises the following steps:

[0025] Step S21: fully drying the calcium titanate block raw material in an oven at 90-100° C.;

[0026] Step S22: adding anhydrous ethanol to the dried calcium titanate, the mass volume ratio of calcium titanate to anhydrous ethanol being 5g:2ml, and then using zirconium oxide balls as ball milling media, and ball milling at a speed of 200r / min in a ball milling jar for 12h;

[0027] Step S23: placing the slurry obtained by ball milling in an oven at 80-90° C. and drying for 10-12 hours, and passing through a 100-mesh sieve to obtain calcium titanate powder;

[0028] Step S24: dissolving calcium titanate powder, Fe(NO3)3·9H2O and Ba(NO3)2 in water at a mass ratio of 50:10:1, mechanically stirring to completely dissolve, adjusting the pH to 9 with sodium hydroxide solution, and continuously stirring for co-precipitation for 3-7 hours; filtering the precipitate and washing it with deionized water until the pH of the filtrate is 7, and then drying and grinding the retained material on the filter membrane to obtain barium ferrite modified calcium titanate powder;

[0029] Step S25: adding the barium ferrite modified calcium titanate powder obtained in step S24 to a polyvinyl alcohol slurry with a mass concentration of 30%, the mass volume ratio of the barium ferrite modified calcium titanate powder to the polyvinyl alcohol slurry with a mass concentration of 30% is 1g:5-10ml, stirring at 70-90°C for 1-3h; then pouring the above mixed solution into a mold preheated at 90°C for molding, the molding temperature is -10 to -20°C, and the molding time is 20-30h;

[0030] Step S26: Place the formed sheet material obtained in step S25 into a muffle furnace and pre-sinter at 150° C. for 30 min, then heat to 1100° C. at a rate of 10° C. / min and calcine for 8 h, and cool to room temperature to obtain a modified porous calcium titanate sheet carrier.

[0031] The present invention also discloses a method for preparing a culture matrix, comprising the following steps:

[0032] Step S1: preparing a composite culture solution, wherein the components and concentrations contained in the composite culture solution are: glucose: 360 mg / L, sodium lactate: 3.50 g / L, NH4Cl: 1.00 g / L, K2HPO4: 0.50 g / L, MgCl2·6H2O: 0.04 g / L, CaCl2·2H2O: 0.04 g / L, Na2SO4: 1.50 g / L;

[0033] Step S2: immersing the modified porous calcium titanate sheet carrier in the composite culture solution and leaving it to stand at 25° C. until the carrier is saturated with nutrients; after the immersion is completed, taking out the nutrient-loaded carrier and drying it naturally;

[0034] Step S3: dissolving 15-25 g of silk fibroin in 1.5-2.5 L of deionized water, stirring at 80° C. for 40-50 minutes to form a solution, adding 2% glacial acetic acid to the solution, and continuing to mechanically stir at 300 rpm for 40-50 minutes to obtain a silk fibroin sustained-release solution;

[0035] Step S4: evenly apply the silk fibroin sustained-release solution obtained in step S3 to the surface of the nutrient-loaded carrier obtained in step S2, and dry it at 40°C; repeat the application and drying steps 3-5 times to finally obtain a calcium titanate-based sustained-release culture matrix with a 100-200 μm thick silk fibroin film attached.

[0036] Preferably, in step S2, the method for preparing the modified porous calcium titanate sheet carrier comprises the following steps:

[0037] Step S21: fully drying the calcium titanate block raw material in an oven at 90-100° C.;

[0038] Step S22: adding anhydrous ethanol to the dried calcium titanate, the mass volume ratio of calcium titanate to anhydrous ethanol being 5g:2ml, and then using zirconium oxide balls as ball milling media, and ball milling at a speed of 200r / min in a ball milling jar for 12h;

[0039] Step S23: placing the slurry obtained by ball milling in an oven at 80-90° C. and drying for 10-12 hours, and passing through a 100-mesh sieve to obtain calcium titanate powder;

[0040] Step S24: dissolving calcium titanate powder, Fe(NO3)3·9H2O and Ba(NO3)2 in water at a mass ratio of 50:10:1, mechanically stirring to completely dissolve, adjusting the pH to 9 with sodium hydroxide solution, and continuously stirring for co-precipitation for 3-7 hours; filtering the precipitate and washing it with deionized water until the pH of the filtrate is 7, and then drying and grinding the retained material on the filter membrane to obtain barium ferrite modified calcium titanate powder;

[0041] Step S25: adding the barium ferrite modified calcium titanate powder obtained in step S24 to a polyvinyl alcohol slurry with a mass concentration of 30%, the mass volume ratio of the barium ferrite modified calcium titanate powder to the polyvinyl alcohol slurry with a mass concentration of 30% is 1g:5-10ml, stirring at 70-90°C for 1-3h; then pouring the above mixed solution into a mold preheated at 90°C for molding, the molding temperature is -10 to -20°C, and the molding time is 20-30h;

[0042] Step S26: Place the formed sheet material obtained in step S25 into a muffle furnace and pre-sinter at 150° C. for 30 min, then heat to 1100° C. at a rate of 10° C. / min and calcine for 8 h, and cool to room temperature to obtain a modified porous calcium titanate sheet carrier.

[0043] The present invention also discloses a method for preparing a modified porous calcium titanate sheet carrier, comprising the following steps:

[0044] Step S21: fully drying the calcium titanate block raw material in an oven at 90-100° C.;

[0045] Step S22: adding anhydrous ethanol to the dried calcium titanate, the mass volume ratio of calcium titanate to anhydrous ethanol being 5g:2ml, and then using zirconium oxide balls as ball milling media, and ball milling at a speed of 200r / min in a ball milling jar for 12h;

[0046] Step S23: placing the slurry obtained by ball milling in an oven at 80-90° C. and drying for 10-12 hours, and passing through a 100-mesh sieve to obtain calcium titanate powder;

[0047] Step S24: dissolving calcium titanate powder, Fe(NO3)3·9H2O and Ba(NO3)2 in water at a mass ratio of 50:10:1, mechanically stirring to completely dissolve, adjusting the pH to 9 with sodium hydroxide solution, and continuously stirring for co-precipitation for 3-7 hours; filtering the precipitate and washing it with deionized water until the pH of the filtrate is 7, and then drying and grinding the retained material on the filter membrane to obtain barium ferrite modified calcium titanate powder;

[0048] Step S25: adding the barium ferrite modified calcium titanate powder obtained in step S24 to a polyvinyl alcohol slurry with a mass concentration of 30%, the mass volume ratio of the barium ferrite modified calcium titanate powder to the polyvinyl alcohol slurry with a mass concentration of 30% is 1g:5-10ml, stirring at 70-90°C for 1-3h; then pouring the above mixed solution into a mold preheated at 90°C for molding, the molding temperature is -10 to -20°C, and the molding time is 20-30h;

[0049] Step S26: Place the formed sheet material obtained in step S25 into a muffle furnace and pre-sinter at 150° C. for 30 min, then heat to 1100° C. at a rate of 10° C. / min and calcine for 8 h, and cool to room temperature to obtain a modified porous calcium titanate sheet carrier.

[0050] The present invention provides a device for in-situ culture and collection of peripheral organisms on an artificial matrix. It has the following beneficial effects:

[0051] 1. Solar panels convert solar energy into electrical energy without the need for an external power source, providing power for water pumps to achieve hydraulic flow and create conditions for the growth of surrounding organisms.

[0052] 2. The buffer grid can completely confine the culture matrix inside the placement slot to avoid damage to the culture matrix caused by water erosion. It can also block substances with larger particle sizes to effectively prevent other debris from adhering to the culture matrix or damaging the culture matrix and affecting the growth of surrounding organisms. At the same time, it can buffer water flows with higher flow rates.

[0053] 3. By setting up freely detachable detachable enclosures and buffer grilles, it is convenient to collect the growing surrounding organisms, thereby effectively realizing the two major functions of in-situ cultivation and collection.

[0054] 4. By setting up support columns, the overall inclination of the device can be adjusted according to the environmental terrain to maintain a horizontal state.

[0055] 5. The modified calcium titanate adsorption carrier sheet is used as the loading matrix material for nutrients such as N and P in the culture matrix, and is modified with barium ferrite magnetic powder. A magnetic field is formed to enhance the initial adsorption of pericellular biological bacteria on the surface of calcium titanate, so as to facilitate the subsequent stable growth of the biofilm. At the same time, calcium can serve as a bridge between phosphate and protein carboxyl groups in the cell membrane, which can maintain the structure of the pericellular biofilm and form a stable micro-ecosystem.

[0056] 6. Silk fibroin is applied to the surface of the carrier to form a slow-release film with a mesh structure, which continuously provides organic carbon and nutrient elements for the growth of periphyton on the carrier. At the same time, silk fibroin also has good biocompatibility, cell adhesion and mechanical strength, which is conducive to the attachment and growth of periphyton and the stability of calcium titanate carrier. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the present invention or the technical solutions in the prior art, the drawings required for describing the prior art are briefly introduced below.

[0058] Figure 1 A schematic diagram of the structure of the present invention;

[0059] Figure 2 A schematic diagram of the structure of the present invention;

[0060] Figure 3 A schematic diagram of the structure of the water pump connection in the present invention;

[0061] Figure 4 A schematic diagram of the structure of the support column in the present invention;

[0062] Figure 5 A flowchart of the method for preparing the calcium titanate-based sustained-release culture matrix of the present invention;

[0063] Figure 6 A flowchart of the preparation method of the modified porous calcium titanate sheet carrier of the present invention;

[0064] Description of the numbers in the figure:

[0065] 1. Collector body; 2. Placement slot; 3. Removable enclosure; 4. Culture matrix; 5. Buffer grid; 6. Protective cover; 7. Water pump; 8. Water inlet pipe; 9. Water outlet pipe; 10. Solar panel; 11. pH meter; 12. Support column; 81. Water inlet main pipe; 82. Water inlet branch pipe; 83. Connecting pipe; 121. Fixed column; 122. Adjusting column. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solutions and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention.

[0067] Embodiment 1, as Figures 1 to 4As shown, a device for in-situ culturing and collecting surrounding organisms on an artificial matrix comprises a collector body 1, the collector is 50 cm long, 25 cm wide and 30 cm high, a placement slot 2 is provided on the front side of the collector body 1, a detachable enclosure 3 is embedded on the left and right sides of the placement slot 2, a culture matrix 4 is installed in the placement slot 2, the culture matrix 4 is vertically suspended and fixed on the inner wall of the placement slot 2, a buffer grille 5 is provided on the outside of the culture matrix 4, and both ends of the buffer grille 5 are clamped on the inner side of the detachable enclosure 3;

[0068] A protective cover 6 is installed on the rear side of the collector body 1, and a water pump 7 is installed inside the protective cover 6. The water inlet end of the water pump 7 is connected to one end of the water inlet pipeline 8, and the other end of the water inlet pipeline 8 passes through the protective cover 6 and the collector body 1 in sequence and is connected to the inner cavity of the placement slot 2. The end face of the water inlet pipeline 8 is kept at a distance from the inner side of the culture matrix 4 to ensure that the culture matrix 4 will not be sucked into the water inlet of the water inlet pipeline 8 and blocked when water is inlet; the water outlet end of the water pump 7 is connected to one end of the water outlet pipeline 9, and the other end of the water outlet pipeline 9 extends to the outside of the protective cover 6. A solar power generation panel 10 is also fixedly installed above the protective cover 6 through a mounting rod, and the solar power generation panel 10 is connected to the water pump 7 through a power supply circuit. During the entire operation process, the protective cover 6 is in a closed state. The crystals of the solar power generation panel 10 are exposed outside the protective cover, and the upper surface of the protective cover 6 and the lower wires of the solar power generation panel 10 are bonded with hot melt adhesive to effectively prevent water from penetrating into the protective cover 6.

[0069] Working principle:

[0070] First, turn on the switch of the water pump 7. At this time, the device is not immersed in the water. The solar panel 10 starts to work. The power of the solar panel 10 is 10W; the flow rate of the water pump 7 is 0.5m 3 / h, head is 3m, power is 7W. In this embodiment, the water pump 7 adopts a vertical axial flow pump;

[0071] When in use, a wetland or river channel with a water level of not less than 30 cm is selected for placement, and when the entire device is immersed in the water body, the crystalline silicon cell part of the solar panel 10 is controlled to be exposed to the air and cannot contact the water body; then the water pump 7 starts to work, so that the water flow will first pass through the buffer grid 5, and the buffer grid 5 can block materials with larger particle sizes such as leaves and stones, thereby effectively preventing other debris from adhering to the culture matrix or damaging the culture matrix and affecting the growth of the surrounding organisms, and at the same time, it can buffer the water flow with a larger flow rate; so that the water flow rate is relatively weakened, and then after flowing through the culture matrix 4, it enters the water inlet pipe 8, and after passing through the water pump 7, the water flow is discharged from the water outlet pipe 9 to the external water body. During the cultivation process, nutrient solution can also be appropriately added to the water body to create a good environment for the growth of surrounding organisms.

[0072] After waiting for the cultivation cycle to end, take the device out of the water body, turn off the switch of the water pump 7, remove the detachable enclosure 3 from the left and right sides of the placement slot 2, open the buffer grille 5, and take out the culture matrix 4. The culture matrix 4 is divided into an inner side and an outer side. The outer side is the side facing the buffer grille 5, and the inner side is the side facing the water inlet pipe 8. Since the flushing direction of the water flow is from the outside to the inside, the periphyton generally grows on the inner side of the culture matrix 4. Therefore, after taking out the culture matrix 4, the periphyton can be obtained by cutting or peeling with tools.

[0073] The whole process converts solar energy into electrical energy through the solar panel 10, and does not require an external power supply. It provides power for the water pump to achieve hydraulic flow and create conditions for the growth of peripheral organisms. The buffer grid 5 can make the culture matrix 4 completely confined inside the placement slot 2 to avoid the culture matrix 4 being damaged by water erosion and can also block larger particle size substances. The detachable enclosure 3 and the buffer grid 5 can be freely disassembled, so as to facilitate the collection of the growing peripheral organisms, thereby effectively realizing the two major functions of in situ culture and collection.

[0074] Embodiment 2, as a further preferred embodiment of embodiment 1, a pH meter 11 is also installed in the protective cover 6, and the pH meter 11 includes an instrument body and a detection probe, wherein the instrument body is arranged inside the protective cover 6, and the detection probe of the pH meter 11 passes through the protective cover 6 and the collector body 1 in turn and is located in the inner cavity of the placement slot 2, and contacts with water during operation, and is used to detect the pH index of the water quality in the placement slot 2 in real time. The signal output end of the detection probe is connected to the instrument body, and a communication module is also provided in the instrument body, which is used to transmit the water quality pH index detected by the detection probe to the terminal in real time; in addition, the instrument body itself also has its own power supply, which is used to power the entire pH meter 11. In this embodiment, the detection probe of the pH meter is a plastic shell electrode. During use, the water level line needs to reach the height of the detection probe of the pH meter 11 to prevent the pH meter 11 from not working; when the water flows through the culture matrix 4, the water quality pH can be detected by the detection probe of the pH meter 11, and the water quality pH can be transmitted to the terminal in real time to facilitate subsequent scientific research. In this embodiment, the detection probe of the pH meter 11 is higher than the water inlet pipeline 8. Thereby, the entire power system formed by the pH meter 11 and the water pump 7 is independent of each other to avoid mutual influence.

[0075] Embodiment 3, as a further preferred solution of embodiment 1, the inner walls on the left and right sides of the placement slot 2 are provided with engaging grooves, and the removable enclosure 3 is inserted into the engaging grooves; the inner wall of the removable enclosure 3 is provided with limiting grooves, and the two ends of the buffer grille 5 are fixedly engaged in the limiting grooves. During installation, the removable enclosure 3 can be directly inserted into the engaging grooves, and then the two ends of the buffer grille 5 can be engaged in the limiting grooves of the inner wall of the removable enclosure 3, so that the culture matrix 4 can be completely confined inside the placement slot 2, thereby effectively avoiding water scouring and damage; and after the culture cycle is over, the buffer grille 5 can also be directly taken out to facilitate the removal of the culture matrix 4.

[0076] Embodiment 4, as Figure 3 As shown, as a further preferred scheme of Example 1, the water inlet pipeline 8 includes a water inlet main pipe 81 and five water inlet branch pipes 82, one end of the water inlet main pipe 81 is connected to the water inlet end of the water pump 7, and the other end of the water inlet main pipe 81 is connected to one end of each water inlet branch pipe 82 through a connecting pipe 83, the other ends of the five water inlet branch pipes 82 are evenly arranged along the horizontal axis of the collector body 1 and are connected to the inner cavity of the placement slot 2, and each water inlet branch pipe 82 is arranged perpendicular to the culture matrix 4 and is separated from the culture matrix 4 by a distance.

[0077] The diameters of the five water inlet branches 82 are all equal. The five water inlet branches 82 are used to create a uniform water flow along the length direction of the collector body 1 and perpendicular to the culture matrix 4, thereby effectively avoiding the problem of uneven hydraulic force caused by a single water inlet, which in turn distorts the shape of the culture matrix 4. There is a distance between the water inlet of each water inlet branch 82 and the culture matrix 4. This ensures that the culture matrix 4 will not be sucked into the water inlet and blocked when water is entering. During operation, the water flows into each water inlet branch 82 after flowing through the culture matrix 4, and then flows into the connecting pipe 83 along each water inlet branch 82, and then passes through the water pump 7, and is discharged from the outlet pipe 9 to the external water body.

[0078] Embodiment 5, as Figure 4As shown, as a further preferred solution of the first embodiment, considering that when the bottom of the device is in a riverbed with a lot of bottom mud, the bottom mud is soft and the whole device is easy to sink into the riverbed; therefore, two support columns 12 are respectively installed under the collector body 1 and under the protective cover 6. Among them, the support column 12 includes a fixed column 121 and an adjustment column 122, and the upper end of the fixed column 121 is respectively fixed under the collector body 1 and under the protective cover 6, wherein the height of the two fixed columns 121 located under the collector body 1 is less than the height of the two fixed columns 121 under the protective cover 6, and the height of the entire support column 12 is less than the height of the collector body 1 and the height of the protective cover 6; the lower end face of the fixed column 121 is provided with an adjustment hole along the axial direction, and the upper end of the adjustment column 122 is inserted into the installation hole, and the side of the fixed column 121 is evenly provided with four outer holes along the axial direction, and the side of the adjustment column 122 is evenly provided with four inner holes along the axial direction, and the outer holes correspond to the inner holes, and the inner holes are provided with threads, and the screws pass through the outer holes and the inner holes in turn and are connected and fixed with the inner holes through the threads.

[0079] When placing the entire device on the riverbed, the length of each support column 12 can be adjusted according to the terrain conditions, such as the inclination of the riverbed or the inclined river slope, by adjusting the relative position of each adjusting column 122 in the mounting hole of the fixing column 121, so that the bottom of the device is just out of contact with the bottom mud and the entire device can be placed as horizontally as possible; when the length of each support column 12 is adjusted to a suitable position, screws can be passed through the outer hole and the inner hole and connected and fixed to the inner hole by threads to limit the length of each support column 12.

[0080] Embodiment 6, as a further preferred solution of embodiment 1, the collector body 1 and the detachable enclosure 3 are both made of stainless steel; the buffer grid 5 is made of polyvinyl chloride; and a nylon mesh with a length and width suitable for the collector body 1 is selected as the culture matrix 4.

[0081] Embodiment seven, as Figure 5 to Figure 6 As shown, as a further preferred embodiment of Example 1, the culture matrix 4 is a calcium titanate-based sustained-release culture matrix, and its preparation method includes the following steps:

[0082] Step S1: preparing a composite culture solution that can provide nutrients such as C, N, and P for Zhou Cong Bio, wherein the components and concentrations contained in the composite culture solution are as follows: glucose: 360 mg / L, sodium lactate: 3.50 g / L, NH4Cl: 1.00 g / L, K2HPO4: 0.50 g / L, MgCl2·6H2O: 0.04 g / L, CaCl2·2H2O: 0.04 g / L, and Na2SO4: 1.50 g / L;

[0083] Step S2: immersing the modified porous calcium titanate sheet carrier in the composite culture solution and leaving it to stand at 25° C. until the carrier is saturated with nutrients; after the immersion is completed, taking out the nutrient-loaded carrier and drying it naturally;

[0084] Step S3: dissolving 25 g of silk fibroin in 2.5 L of deionized water, stirring at 80° C. for 40-50 minutes to form a solution, adding 2% glacial acetic acid to the solution, and continuing to mechanically stir at 300 rpm for 40-50 minutes to obtain a silk fibroin sustained-release solution;

[0085] Step S4: evenly apply the silk fibroin sustained-release solution obtained in step S3 to the surface of the nutrient-loaded carrier obtained in step S2, and dry it at 40°C; repeat the application and drying steps 3-5 times to finally obtain a calcium titanate-based sustained-release culture matrix with a 100-200 μm thick silk fibroin film attached.

[0086] The present invention obtains a culture matrix that can stably maintain the growth of periphyton organisms for a long time through the above steps. The modified calcium titanate adsorption carrier sheet is immersed in a culture solution containing organic carbon sources and nutrient elements such as vitamins, nutrient salts, and trace elements, and the silk fibroin is applied to the surface of the carrier after drying. After drying, a layer of slow-release film with a mesh structure is formed on the surface of the carrier, which continuously provides organic carbon and nutrient elements for the growth of periphyton organisms on the carrier. At the same time, the silk fibroin also has good biocompatibility, cell adhesion and mechanical strength, which is conducive to the attachment and growth of periphyton organisms and the stability of the calcium titanate carrier.

[0087] Further, in step S2, the method for preparing the modified porous calcium titanate sheet carrier comprises the following steps:

[0088] Step S21: fully drying the calcium titanate block raw material in an oven at 90-100° C.;

[0089] Step S22: adding anhydrous ethanol to the dried calcium titanate, the mass volume ratio of calcium titanate to anhydrous ethanol being 5g:2ml, and then using zirconium oxide balls as ball milling media, and ball milling at a speed of 200r / min in a ball milling jar for 12h;

[0090] Step S23: placing the slurry obtained by ball milling in an oven at 80-90° C. and drying for 10-12 hours, and passing through a 100-mesh sieve to obtain calcium titanate powder;

[0091] Step S24: dissolving calcium titanate powder, Fe(NO3)3·9H2O and Ba(NO3)2 in water at a mass ratio of 50:10:1, mechanically stirring at 200 rpm for 30 min until completely dissolved, adjusting the pH to 9 with 1.5 mol / L sodium hydroxide solution, and continuing to stir for co-precipitation for 5 h; filtering the precipitate and washing it with deionized water until the pH of the filtrate is 7, and then drying and grinding the retentate on the filter membrane to obtain barium ferrite-modified calcium titanate powder;

[0092] Step S25: adding the barium ferrite modified calcium titanate powder obtained in step S24 to a polyvinyl alcohol slurry with a mass concentration of 30%, the mass volume ratio of the barium ferrite modified calcium titanate powder to the polyvinyl alcohol slurry with a mass concentration of 30% is 1g:5ml, stirring at 80°C for 2h; then pouring the above mixture into a 300×200×5mm mold preheated at 90°C for molding, the molding temperature is -15°C, and the molding time is 24h;

[0093] Step S26: Place the formed sheet material obtained in step S25 into a muffle furnace and pre-sinter at 150° C. for 30 min, then heat to 1100° C. at a rate of 10° C. / min and calcine for 8 h, and cool to room temperature to obtain a modified porous calcium titanate sheet carrier.

[0094] Among them, calcium titanate is a natural porous adsorption material with strong adsorption capacity for inorganic nutrients, and can be used to load nutrients such as N and P in the culture matrix. At the same time, calcium can serve as a bridge between phosphate and protein carboxyl in the cell membrane, which can maintain the structure of the pericyte biofilm and form a stable micro-ecosystem. Therefore, the present invention selects calcium titanate as the loading matrix material of the pericyte biological culture matrix. In addition, in order to enhance the biological affinity of calcium titanate, it is further modified with barium ferrite magnetic powder, and a magnetic field is formed to enhance the initial adsorption of pericyte biological bacteria on the surface of calcium titanate, which is more conducive to the stable growth of the subsequent biofilm.

[0095] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a culture matrix, characterized in that: The following steps are involved: Step S1: preparing a composite culture solution, wherein the components and concentrations contained in the composite culture solution are: glucose: 360 mg / L, sodium lactate: 3.50 g / L, NH4Cl: 1.00 g / L, K2HPO4: 0.50 g / L, MgCl2·6H2O: 0.04 g / L, CaCl2·2H2O: 0.04 g / L, Na2SO4: 1.50 g / L; Step S2: immersing the modified porous calcium titanate sheet carrier in the composite culture solution and leaving it to stand at 25° C. until the carrier is saturated with nutrients; after the immersion is completed, taking out the nutrient-loaded carrier and drying it naturally; Step S3: dissolving 15-25 g of silk fibroin in 1.5-2.5 L of deionized water, stirring at 80° C. for 40-50 minutes to form a solution, adding 2% glacial acetic acid to the solution, and continuing to mechanically stir at 300 rpm for 40-50 minutes to obtain a silk fibroin sustained-release solution; Step S4: evenly apply the silk fibroin sustained-release solution obtained in step S3 to the surface of the nutrient-loaded carrier obtained in step S2, and dry it at 40°C; repeat the application and drying steps 3-5 times to finally obtain a calcium titanate-based sustained-release culture matrix with a 100-200 μm thick silk fibroin film attached.

2. The method for preparing a culture matrix according to claim 1, characterized in that: In step S2, the method for preparing the modified porous calcium titanate sheet carrier comprises the following steps: Step S21: fully drying the calcium titanate block raw material in an oven at 90-100° C.; Step S22: adding anhydrous ethanol to the dried calcium titanate, the mass volume ratio of calcium titanate to anhydrous ethanol being 5g:2ml, and then using zirconium oxide balls as ball milling media, and ball milling at a speed of 200r / min in a ball milling jar for 12h; Step S23: placing the slurry obtained by ball milling in an oven at 80-90° C. and drying for 10-12 hours, and passing through a 100-mesh sieve to obtain calcium titanate powder; Step S24: dissolving calcium titanate powder, Fe(NO3)3·9H2O and Ba(NO3)2 in water at a mass ratio of 50:10:1, mechanically stirring to completely dissolve, adjusting the pH to 9 with sodium hydroxide solution, and continuously stirring for co-precipitation for 3-7 hours; filtering the precipitate and washing it with deionized water until the pH of the filtrate is 7, and then drying and grinding the retained material on the filter membrane to obtain barium ferrite modified calcium titanate powder; Step S25: adding the barium ferrite modified calcium titanate powder obtained in step S24 to a polyvinyl alcohol slurry with a mass concentration of 30%, the mass volume ratio of the barium ferrite modified calcium titanate powder to the polyvinyl alcohol slurry with a mass concentration of 30% is 1g:5-10ml, stirring at 70-90°C for 1-3h; then pouring the above mixed solution into a mold preheated at 90°C for molding, the molding temperature is -10 to -20°C, and the molding time is 20-30h; Step S26: Place the formed sheet material obtained in step S25 into a muffle furnace and pre-sinter at 150° C. for 30 min, then heat to 1100° C. at a rate of 10° C. / min and calcine for 8 h, and cool to room temperature to obtain a modified porous calcium titanate sheet carrier.

3. A method for preparing a modified porous calcium titanate sheet carrier, characterized in that: The following steps are involved: Step S21: fully drying the calcium titanate block raw material in an oven at 90-100° C.; Step S22: adding anhydrous ethanol to the dried calcium titanate, the mass volume ratio of calcium titanate to anhydrous ethanol being 5g:2ml, and then using zirconium oxide balls as ball milling media, and ball milling at a speed of 200r / min in a ball milling jar for 12h; Step S23: placing the slurry obtained by ball milling in an oven at 80-90° C. and drying for 10-12 hours, and passing through a 100-mesh sieve to obtain calcium titanate powder; Step S24: dissolving calcium titanate powder, Fe(NO3)3·9H2O and Ba(NO3)2 in water at a mass ratio of 50:10:1, mechanically stirring to completely dissolve, adjusting the pH to 9 with sodium hydroxide solution, and continuously stirring for co-precipitation for 3-7 hours; filtering the precipitate and washing it with deionized water until the pH of the filtrate is 7, and then drying and grinding the retained material on the filter membrane to obtain barium ferrite modified calcium titanate powder; Step S25: adding the barium ferrite modified calcium titanate powder obtained in step S24 to a polyvinyl alcohol slurry with a mass concentration of 30%, the mass volume ratio of the barium ferrite modified calcium titanate powder to the polyvinyl alcohol slurry with a mass concentration of 30% is 1g:5-10ml, stirring at 70-90°C for 1-3h; then pouring the above mixed solution into a mold preheated at 90°C for molding, the molding temperature is -10 to -20°C, and the molding time is 20-30h; Step S26: Place the formed sheet material obtained in step S25 into a muffle furnace and pre-sinter at 150° C. for 30 min, then heat to 1100° C. at a rate of 10° C. / min and calcine for 8 h, and cool to room temperature to obtain a modified porous calcium titanate sheet carrier.

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