Poly(acrylamide-methylacrylamide primary amine salt) with a random structure, its preparation method and application

Abstract

The present invention belongs to the technical field of antimicrobial polymer materials, and discloses a poly(acrylamide-methacrylamide primary amine salt) with a random structure, a preparation method thereof, and an application thereof. The poly(acrylamide-methacrylamide primary amine salt) with a random structure has a structural formula as shown in Formula 1: #imgabs0# wherein both m and n are positive integers, and m:n=1:(0.1-9). The poly(acrylamide-methacrylamide primary amine salt) with a random structure has a good antibacterial effect, particularly an inhibitory effect on Foc4 spores. After application to soil, it can be stably adsorbed in the soil, with reduced environmental toxicity, and while improving the physical and chemical properties of the soil, it can achieve long-term inhibition of Foc4 spores in the soil, thereby having a good preventive and control effect on plant fungal diseases such as banana wilt.

Description

Technical Field

[0001] The present invention belongs to the technical field of antibacterial polymer materials, and particularly relates to poly(acrylamide-methacrylamide primary amine salt) with a random structure, and a preparation method and application thereof. Background Art

[0002] Fusarium oxysporum (Foc) is a soil-borne plant pathogenic fungus, a strain of Fusarium oxysporum that causes Fusarium wilt in cultivated bananas. Pathogenic strains are generally divided into four races, of which the most threatening to bananas is the "tropical" race 4 (Foc4) (see: Puhalla J. E. Classification of strains of Fusarium oxysporum on the basis of vegetable compatibility [J]. Canadian Journal of Botany, 1985). Foc4 has become one of the most serious diseases threatening the global banana industry. In soil, most populations are almost incapable of movement without a host. Therefore, it is generally believed that Foc relies on water runoff, animal movement, and human factors for long-distance spread (see: Rekah Y., Shtienberg D., Katan J. Spatial distribution and temporal development of fusarium crown and root rot of tomato and pathogen dissemination in field soil [J]. Phytopathology, 1999). Foc remains dormant in the soil until it is inoculated by host root secretions or by direct contact with susceptible host roots. Once Foc penetrates the plant's cells, it spores and multiplies within the plant. After a few days, it enters the pseudostem, where it blocks the rhizome's vascular bundles, directly affecting nutrient and water transport and leading to plant death (see: LI C, YANG J, LI W, et al. Direct root penetration and rhizome vascular colonization by Fusarium Oxysporum f.sp.cubense are the key steps in the successful infection of Brazil cavendish [J]. Plant Disease, 2017.). In fact, all F. oxysporum species, including Foc, can survive in the soil for 20 years without a host, relying on chlamydospores or chlamydial spores.

[0003] Currently, there are two main chemical control methods for banana wilt: one is to apply fungicides to the affected soil to suppress the number of pathogens in the soil. However, most commercially available fungicides are small molecule fungicides, which are easily transferred with water after application and thus contaminate groundwater, enter the food chain and endanger human health (see the literature: Latz S, Wahida A, Arif A, et al. Preliminary survey of local bacteriophages with lytic activity against multi-drug resistant bacteria [J]. Journal of Basic Microbiology, 2016, 56 (10): 1117-1123); the other is to disinfect the affected soil by heating or fumigating the soil to completely destroy the microbial community structure and stable soil aggregate structure in the soil. After treatment with this method, the soil is difficult to be used for planting immediately.

[0004] Currently, there is no economically feasible method for controlling banana wilt that can both stabilize soil structure and inhibit pathogens. Therefore, it is desirable to provide a hydrophilic fungicide that not only has fungicidal properties but also can improve soil quality, thereby better controlling banana wilt. Summary of the Invention

[0005] The present invention aims to address at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention provides a poly(acrylamide-methacrylamide primary amine salt) having a random structure, as well as its preparation method and application. The poly(acrylamide-methacrylamide primary amine salt) having a random structure has a good inhibitory effect on Fococcus spores. Furthermore, due to the numerous amide groups in the molecular chain, hydrogen bonding allows for stable adsorption in soil, improving soil physical and chemical properties while achieving long-term inhibition of Fococcus spores in the soil. This provides a basis for practical application in the chemical control of plant fungal diseases such as banana wilt.

[0006] A first aspect of the present invention provides a poly(acrylamide-methacrylamide primary amine salt) having a random structure.

[0007] Specifically, the poly(acrylamide-methacrylamide primary amine salt) having a random structure has a structural formula as shown in Formula 1:

[0008]

[0009] Wherein, m and n are both positive integers, and m:n=1:(0.1-9).

[0010] Preferably, m:n=1:(0.11-9); further preferably, m:n=1:(1.5-9); more preferably, m:n=1:(2.33-4).

[0011] Preferably, the poly(acrylamide-methacrylamide primary amine salt) with a random structure further contains a fluorescent group. The fluorescent group has a fluorescent labeling effect, which allows the distribution of the poly(acrylamide-methacrylamide primary amine salt) with a random structure in the soil to be visualized, and is used to detect the adsorption and migration behavior of the poly(acrylamide-methacrylamide primary amine salt) with a random structure in the soil.

[0012] Preferably, the fluorescent group is

[0013] A second aspect of the present invention provides a method for preparing poly(acrylamide-methacrylamide primary amine salt) having a random structure.

[0014] Specifically, the preparation method of poly(acrylamide-methacrylamide primary amine salt) having a random structure comprises the following steps:

[0015] The acryloylethylenediamine hydrochloride monomer, acrylamide monomer and initiator are dissolved in a solvent and subjected to polymerization reaction to obtain the poly(acrylamide-methacrylamide primary amine salt) having a random structure.

[0016] Preferably, the solvent is water, and more preferably, the solvent is deionized water.

[0017] Preferably, the polymerization reaction is carried out under an inert gas atmosphere.

[0018] Preferably, the reactants are stirred during the polymerization reaction.

[0019] Preferably, the stirring rate is 180-260 r / min; further preferably, the stirring rate is 200-250 r / min.

[0020] Preferably, the inert gas includes nitrogen or a rare gas.

[0021] Preferably, the initiator is a water-soluble azo substance, preferably azobisisobutylamidine hydrochloride (AIBA).

[0022] Preferably, the initiator is 0.5%-2.5% of the total mass of the acryloylethylenediamine hydrochloride monomer and the acrylamide monomer, preferably 1%-2%.

[0023] Preferably, the molar ratio of the acryloylethylenediamine hydrochloride monomer to the acrylamide monomer is 1:(0.1-9), and more preferably, the molar ratio of the acryloylethylenediamine hydrochloride monomer to the acrylamide monomer is 1:(2.33-4).

[0024] Preferably, the polymerization reaction temperature is 50°C-80°C; preferably 60°C-65°C.

[0025] Preferably, the polymerization reaction time is 5-8 hours, preferably 7-8 hours.

[0026] Preferably, the fluorescent monomer is mixed with ethylenediamine hydrochloride monomer and acrylamide monomer, and a polymerization reaction is carried out in an inert gas atmosphere to obtain a poly(acrylamide-methacrylamide primary amine salt) having a random structure containing a fluorescent group.

[0027] Preferably, the amount of the fluorescent monomer accounts for 0.1%-0.3% of the total amount of all monomers, preferably 0.2%-0.3%.

[0028] Furthermore, after the polymerization reaction is completed, the product is purified. The specific process of the purification is as follows: the mixed solution obtained after the reaction is placed in a dialysis bag with a molecular weight cutoff of 1000, dialyzed for two days to remove unreacted small molecules, most of the solvent is distilled off under reduced pressure, a large amount of anhydrous ethanol is added to precipitate the poly(acrylamide-methacrylamide primary amine salt) with a random structure, the supernatant is poured out, the precipitation operation is repeated 2-5 times, and after filtering, it is placed in a vacuum oven at 40°C-60°C for drying to obtain the poly(acrylamide-methacrylamide primary amine salt) with a random structure.

[0029] The poly(acrylamide-methacrylamide primary amine salt) with a random structure is a white solid substance.

[0030] The poly(acrylamide-methacrylamide primary amine salt) containing a fluorescent group and having a random structure emits bright yellow-green light under irradiation with light of a specific wavelength.

[0031] The third aspect of the present invention provides the use of poly(acrylamide-methacrylamide primary amine salt) having a random structure.

[0032] Application of the above-mentioned poly(acrylamide-methacrylamide primary amine salt) with random structure in soil.

[0033] Preferably, the application includes preventing and controlling banana wilt and improving soil structure.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The present invention provides a poly(acrylamide-methacrylamide primary amine salt) having a random structure. The poly(acrylamide-methacrylamide primary amine salt) having a random structure has a good antibacterial effect, especially an inhibitory effect on Foc4 spores. After being applied to the soil, it can be stably adsorbed in the soil, with reduced environmental toxicity, and improve the physical and chemical properties of the soil while achieving long-term inhibition of Foc4 spores in the soil, thereby having a good preventive and control effect on plant fungal diseases such as banana wilt.

[0036] (2) The preparation method of the present invention can roughly control the product structure and molecular weight by controlling the feed ratio of propylene glycol diamine hydrochloride to acrylamide, the reaction yield is high, and the post-processing is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is the infrared spectrum of the poly(acrylamide-methacrylamide primary amine salt) with random structure prepared in Example 1 of the present invention;

[0038] Figure 2 This is an emission spectrum diagram of the fluorescence spectrum of the poly(acrylamide-methacrylamide primary amine salt) with a random structure and containing fluorescent groups prepared in Example 9 of the present invention;

[0039] Figure 3 Schematic diagram of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MFC) of the products obtained in Comparative Example 1 and Examples 1-8 of the present invention against Foc4;

[0040] Figure 4 Schematic diagram of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MFC) of the products obtained in Comparative Example 1 and Examples 1-8 of the present invention against Candida albicans;

[0041] Figure 5 Schematic diagram of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MFC) of the products obtained in Comparative Example 1 and Examples 1-8 of the present invention against Staphylococcus albus;

[0042] Figure 6 Schematic diagram of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MFC) of the products obtained in Comparative Example 1 and Examples 1-8 of the present invention against Escherichia coli E. coli;

[0043] Figure 7 Schematic diagram of the adsorption characteristics of the fluorescent products corresponding to the products obtained in Examples 1-3 of the present invention in soil;

[0044] Figure 8 Schematic diagram of the adsorption characteristics of the fluorescent products corresponding to the products obtained in Examples 4-6 of the present invention in soil;

[0045] Figure 9 Schematic diagram of the adsorption characteristics of the fluorescent products corresponding to the products obtained in Examples 7-8 and Comparative Example 1 of the present invention in soil. DETAILED DESCRIPTION

[0046] In order to make the technical solution of the present invention more clearly understood by those skilled in the art, the following examples are given for illustration. It should be noted that the following examples do not limit the scope of protection claimed by the present invention.

[0047] Unless otherwise specified, the raw materials, reagents, or devices used in the following examples can be obtained from conventional commercial sources or by existing known methods.

[0048] Poly(acrylamide-methacrylamide primary amine salt) having a random structure has a structural formula as shown in Formula 1:

[0049]

[0050] Wherein, m and n are both positive integers, and m:n=1:(0.1-9).

[0051] The poly(acrylamide-methacrylamide primary amine salt) with random structure further contains a fluorescent group, which is

[0052]

[0053] The preparation method of poly(acrylamide-methacrylamide primary amine salt) having a random structure comprises the following steps:

[0054] Acryloylethylenediamine hydrochloride monomer, acrylamide monomer and initiator are dissolved in a solvent and polymerized to prepare poly(acrylamide-methacrylamide primary amine salt) with a random structure.

[0055] The solvent is deionized water.

[0056] The polymerization reaction was carried out under an inert gas atmosphere.

[0057] During the polymerization reaction, the reactants are stirred.

[0058] The stirring rate is 200-250r / min.

[0059] Inert gases include nitrogen or noble gases.

[0060] The initiator was azobisisobutylamidine hydrochloride (AIBA).

[0061] The initiator is 0.5%-2.5% of the total mass of the acryloylethylenediamine hydrochloride monomer and the acrylamide monomer.

[0062] The molar ratio of acryloylethylenediamine hydrochloride monomer to acrylamide monomer is 1:(0.1-9).

[0063] The polymerization temperature is 50°C-80°C.

[0064] The polymerization reaction time is 5-8 hours.

[0065] After the polymerization reaction is completed, the product is purified. The specific purification process is as follows: the mixed solution obtained after the reaction is placed in a dialysis bag with a molecular weight cut-off of 1000, dialyzed for two days to remove unreacted small molecules, most of the solvent is distilled off under reduced pressure, a large amount of anhydrous ethanol is added to precipitate the poly(acrylamide-methacrylamide primary amine salt) with a random structure, the supernatant is poured out, and the precipitation operation is repeated 2-5 times. After filtering, the product is placed in a vacuum oven at 40°C-60°C and dried to obtain the poly(acrylamide-methacrylamide primary amine salt) with a random structure.

[0066] The synthetic route of the poly(acrylamide-methacrylamide primary amine salt) having a random structure is as follows:

[0067]

[0068] Comparative Example 1: Preparation of polymethacrylamide primary amine salt

[0069] The preparation of polymethacrylamide primary amine salt comprises the following steps:

[0070] 7.08 g of acrylamide diamine hydrochloride monomer (denoted as AM-AH) was dissolved in 60 mL of deionized water and placed in a three-necked flask. The mixture was stirred with a magnetic stirrer in a nitrogen atmosphere and heated to 60°C. After the temperature stabilized, 0.233 g of azobisisobutylamidine hydrochloride (AIBA) dissolved in deionized water was slowly added dropwise to the three-necked flask. The polymerization reaction took 8 hours. After the reaction, the resulting mixture was dialyzed with a 1000 molecular weight cutoff dialysis bag for two days. The solvent was removed by vacuum distillation. The product was then precipitated with anhydrous acetone and washed repeatedly three times. The resulting light yellow solid was dried, ground, and sealed for storage to obtain polymethacrylamide primary amine salt (denoted as PAH).

[0071] The reaction equation of the polymethacrylamide primary amine salt of Comparative Example 1 is as follows:

[0072]

[0073] Example 1: Preparation of Poly(Acrylamide-Methacrylamide Primary Amine Salt) with Random Structure

[0074] The invention relates to a poly(acrylamide-methacrylamide primary amine salt) having a random structure, wherein the molar ratio of acryloylethylenediamine hydrochloride to acrylamide in the structure is 2:8.

[0075] The preparation method of poly(acrylamide-methacrylamide primary amine salt) having a random structure comprises the following steps:

[0076] 1.01 g of acryloylethylenediamine hydrochloride monomer (denoted as AM-AH) and 1.743 g of acrylamide monomer (denoted as AM) were dissolved in 60 mL of deionized water and placed in a three-necked flask. A mechanical stirrer was connected and stirred at 60° C. in a nitrogen atmosphere. After the temperature stabilized, 0.166 g of azobisisobutylamidine hydrochloride (AIBA) dissolved in deionized water was slowly added dropwise to the three-necked flask. The polymerization reaction took 8 hours. After the reaction, the resulting mixture was dialyzed with a 1000 molecular weight cutoff dialysis bag for two days. The solvent was removed by reduced pressure distillation, and then the product was precipitated with anhydrous ethanol and washed repeatedly three times. The resulting white solid was dried, ground, and sealed for storage to obtain a poly(acrylamide-methacrylamide primary amine salt) with a random structure (denoted as PAM-AH2).

[0077] Example 2: Preparation of Poly(Acrylamide-Methacrylamide Primary Amine Salt) with Random Structure

[0078] The invention relates to a poly(acrylamide-methacrylamide primary amine salt) having a random structure, wherein the molar ratio of acryloylethylenediamine hydrochloride to acrylamide in the structure is 3:7.

[0079] The preparation method of the poly(acrylamide-methacrylamide primary amine salt) having an atactic structure in Example 2 is substantially the same as that in Example 1, except that in Example 2, the amount of acryloylethylenediamine hydrochloride monomer used is 1.21 g, the amount of acrylamide monomer used is 1.218 g, and the amount of azobisisobutylamidine hydrochloride (AIBA) used is 0.133 g. The poly(acrylamide-methacrylamide primary amine salt) having an atactic structure obtained in Example 2 is designated as PAM-AH3.

[0080] Example 3: Preparation of Poly(Acrylamide-Methacrylamide Primary Amine Salt) with Random Structure

[0081] The invention relates to a poly(acrylamide-methacrylamide primary amine salt) having a random structure, wherein the molar ratio of acryloylethylenediamine hydrochloride to acrylamide in the structure is 4:6.

[0082] The preparation method of the poly(acrylamide-methacrylamide primary amine salt) having an atactic structure in Example 3 is substantially the same as that in Example 1, except that in Example 3, the amount of acryloylethylenediamine hydrochloride monomer used is 2.07 g, the amount of acrylamide monomer used is 1.34 g, and the amount of azobisisobutylamidine hydrochloride (AIBA) used is 0.17 g. The poly(acrylamide-methacrylamide primary amine salt) having an atactic structure obtained in Example 3 is designated as PAM-AH4.

[0083] Example 4: Preparation of Poly(Acrylamide-Methacrylamide Primary Amine Salt) with Random Structure

[0084] The invention relates to a poly(acrylamide-methacrylamide primary amine salt) having a random structure, wherein the molar ratio of acryloylethylenediamine hydrochloride to acrylamide in the structure is 5:5.

[0085] The preparation method of the poly(acrylamide-methacrylamide primary amine salt) having an atactic structure in Example 4 is substantially the same as that in Example 1, except that in Example 4, the amount of acryloylethylenediamine hydrochloride monomer used is 3.20 g, the amount of acrylamide monomer used is 1.38 g, and the amount of azobisisobutylamidine hydrochloride (AIBA) used is 0.21 g. The poly(acrylamide-methacrylamide primary amine salt) having an atactic structure obtained in Example 4 is designated as PAM-AH5.

[0086] Example 5: Preparation of Poly(Acrylamide-Methacrylamide Primary Amine Salt) with Random Structure

[0087] The invention relates to a poly(acrylamide-methacrylamide primary amine salt) having a random structure, wherein the molar ratio of acryloylethylenediamine hydrochloride to acrylamide in the structure is 6:4.

[0088] The preparation method of the poly(acrylamide-methacrylamide primary amine salt) having an atactic structure in Example 5 is substantially the same as that in Example 1, except that in Example 5, the amount of acryloylethylenediamine hydrochloride monomer used is 3.56 g, the amount of acrylamide monomer used is 1.024 g, and the amount of azobisisobutylamidine hydrochloride (AIBA) used is 0.2 g. The poly(acrylamide-methacrylamide primary amine salt) having an atactic structure obtained in Example 5 is designated as PAM-AH6.

[0089] Example 6: Preparation of Poly(Acrylamide-Methacrylamide Primary Amine Salt) with Random Structure

[0090] The invention relates to a poly(acrylamide-methacrylamide primary amine salt) having a random structure, wherein the molar ratio of acryloylethylenediamine hydrochloride to acrylamide in the structure is 7:3.

[0091] The preparation method of the poly(acrylamide-methacrylamide primary amine salt) having an atactic structure in Example 6 is substantially the same as that in Example 1, except that in Example 6, the amount of acryloylethylenediamine hydrochloride monomer used is 4.0 g, the amount of acrylamide monomer used is 0.74 g, and the amount of azobisisobutylamidine hydrochloride (AIBA) used is 0.188 g. The poly(acrylamide-methacrylamide primary amine salt) having an atactic structure obtained in Example 6 is designated as PAM-AH7.

[0092] Example 7: Preparation of Poly(Acrylamide-Methacrylamide Primary Amine Salt) with Random Structure

[0093] The invention relates to a poly(acrylamide-methacrylamide primary amine salt) having a random structure, wherein the molar ratio of acryloylethylenediamine hydrochloride to acrylamide in the structure is 8:2.

[0094] The preparation method of the poly(acrylamide-methacrylamide primary amine salt) having an atactic structure in Example 7 is substantially the same as that in Example 1, except that in Example 7, the amount of acryloylethylenediamine hydrochloride monomer used is 3.55 g, the amount of acrylamide monomer used is 0.38 g, and the amount of azobisisobutylamidine hydrochloride (AIBA) used is 0.146 g. The poly(acrylamide-methacrylamide primary amine salt) having an atactic structure prepared in Example 7 is designated as PAM-AH8.

[0095] Example 8: Preparation of Poly(Acrylamide-Methacrylamide Primary Amine Salt) with Random Structure

[0096] The invention relates to a poly(acrylamide-methacrylamide primary amine salt) having a random structure, wherein the molar ratio of acryloylethylenediamine hydrochloride to acrylamide in the structure is 9:1.

[0097] The preparation method of the poly(acrylamide-methacrylamide primary amine salt) having an atactic structure in Example 8 is substantially the same as that in Example 1, except that in Example 8, the amount of acryloylethylenediamine hydrochloride monomer used is 6.0 g, the amount of acrylamide monomer used is 0.288 g, and the amount of azobisisobutylamidine hydrochloride (AIBA) used is 0.22 g. The poly(acrylamide-methacrylamide primary amine salt) having an atactic structure obtained in Example 8 is designated as PAM-AH9.

[0098] Example 9: Preparation of Poly(Acrylamide-Methacrylamide Primary Amine Salt) with Random Structure Containing Fluorescent Groups

[0099] The preparation method of poly(acrylamide-methacrylamide primary amine salt) having a random structure and containing a fluorescent group comprises the following steps:

[0100] 2.80g of acryloylethylenediamine hydrochloride monomer (denoted as AM-AH), 0.302g of acrylamide monomer (denoted as AM) and fluorescent monomer (fluorescent monomer is The amount of the fluorescent monomer accounts for 0.2% of the sum of the amounts of all monomer substances in the reactant system) and is dissolved in 70 mL of deionized water and placed in a three-necked flask. A mechanical stirrer is connected and stirred at 60° C. in a nitrogen atmosphere. After the temperature stabilizes, 0.166 g of azobisisobutylamidine hydrochloride (AIBA) dissolved in deionized water is slowly added dropwise to the three-necked flask. The polymerization reaction takes 8 hours. After the reaction, the reaction mixture is dialyzed with a dialysis bag with a molecular weight cutoff of 1000 for two days, the solvent is removed by distillation under reduced pressure, and then the product is precipitated with anhydrous ethanol and washed repeatedly 3 times. The obtained light yellow solid is dried, ground, and sealed for storage to obtain a poly (acrylamide-methacrylamide primary amine salt) with a random structure containing a fluorescent group (denoted as PAM-AH-FL).

[0101] Product effect testing

[0102] 1. Product Structure or Fluorescence Spectrum Characterization of Example 1 and Example 9

[0103] Figure 1 The infrared spectrum of the poly (acrylamide-methacrylamide primary amine salt) with random structure obtained in Example 1 of the present invention; Figure 1 It can be seen that 3450cm -1 The characteristic absorption peak of NH2 is at 2928cm -1 The antisymmetric stretching vibration absorption peak of methylene is at 1660 cm -1 The stretching vibration absorption peak of C=O corresponds to the stretching vibration of the carbonyl group in the amide. The stretching vibration peak of C=C does not appear, indicating that the double bond disappears.

[0104] Figure 2 This is an emission spectrum diagram of the fluorescence spectrum of the poly(acrylamide-methacrylamide primary amine salt) with a random structure and containing fluorescent groups obtained in Example 9 of the present invention; Figure 2 It can be seen that the maximum emission wavelength of the random-structured poly(acrylamide-methacrylamide primary amine salt) containing fluorescent groups is 521 nm, which is within the visible light range (380 nm-780 nm), indicating that the fluorescence is visible to the naked eye.

[0105] 2. Antibacterial performance test

[0106] Fusarium oxysporum f.sp.cubense (EFSmith) Snyder & Hansen, race 4 (Foc4) was provided by the Fungal Laboratory of the Department of Plant Pathology, College of Plant Protection, South China Agricultural University.

[0107] The products prepared in Comparative Example 1 and Examples 1-8 (poly(acrylamide-methacrylamide primary amine salt) having a random structure) were tested for their inhibitory and bactericidal effects against Gram-positive bacteria (represented by Staphylococcus albus), Gram-negative bacteria (represented by Escherichia coli), pathogenic fungi (represented by Candida albicans), and plant pathogenic fungi (represented by Fusarium oxysporum, Cuban special race 4, Foc4). The specific steps of the antibacterial experiments are briefly described as follows:

[0108] Dilute the bacterial or fungal suspension to 10 5 The concentration of CFU / mL is measured, and the accuracy is ensured by using a blood cell counting plate or a microplate reader. 100 μL of bacterial or fungal suspension and 100 μL of product solutions obtained in Comparative Example 1 and Examples 1-8 of different concentrations are mixed and transferred to a 96-well plate. Blank culture medium replaces the product solutions obtained in Comparative Example 1 and Examples 1-8 as a control, and each treatment is repeated 3 times. After culturing for an appropriate number of days at a temperature of 28°C or 37°C, 50 μL of a certain mass concentration of 2,3,5-triphenyltetrazolium chloride solution (TTC) is added to each well and cultured in the dark for two hours at an appropriate temperature. The minimum inhibitory concentration (MIC) value is the lowest concentration at which no visible bacteria or fungi grow, that is, the lowest concentration of the product obtained in Comparative Example 1 or Examples 1-8 that is not stained red by TTC. Take 5 concentration gradients in sequence from MIC to high concentration, and take 100 μL of each to be inoculated into a solid blank culture medium for culture. The minimum bactericidal concentration (MFC) value is the lowest concentration at which less than 5 colonies are observed to form in the solid culture medium. The results are as follows Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 shown.

[0109] Figure 3 Schematic diagram of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MFC) of the products obtained in Comparative Example 1 and Examples 1-8 of the present invention against Foc4; Figure 4 Schematic diagram of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MFC) of the products obtained in Comparative Example 1 and Examples 1-8 of the present invention against Candida albicans; Figure 5 Schematic diagram of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MFC) of the products obtained in Comparative Example 1 and Examples 1-8 of the present invention against Staphylococcus albus; Figure 6 Schematic diagram of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MFC) of the products obtained in Comparative Example 1 and Examples 1-8 of the present invention against Escherichia coli E. coli.

[0110] from Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 It can be seen that the antibacterial properties of the products produced in Comparative Example 1 and Examples 1-8 of the present invention improve with increasing primary amine group content. For banana wilt pathogen (Foc4), primary amine group contents of 70% and 80% reach their highest levels, demonstrating excellent antibacterial activity. However, antibacterial properties decrease as the primary amine group content approaches 100%. The antibacterial properties also exhibit a similar trend against Candida albicans, another fungus.

[0111] 3. Soil adsorption performance test

[0112] Adsorption performance test: The poly(acrylamide-methacrylamide primary amine salt) with a random structure containing a fluorescent group obtained in Example 9 and the corresponding fluorescent products of Comparative Example 1 and Examples 1-8 (under the premise that the synthesis steps and monomer ratios of the poly(acrylamide-methacrylamide primary amine salt) with a random structure remain unchanged, 0.03% of the fluorescent monomer is added during the monomer dissolution process to obtain the corresponding fluorescent product) were respectively prepared into a 400 mg / L concentration solution with 0.01 mol / L CaCl2 solution. 100 mL of each solution was mixed with 1 g of sterilized soil and placed in a 250 mL conical flask. After sealing, the flask was incubated with a constant temperature shake at 25°C and 200 rpm. Samples were taken at different times and deionized water was added. The absorbance of the supernatant was measured by a fluorescence spectrophotometer. The adsorption amount of the fluorescent series products corresponding to Comparative Example 1 and Examples 1-8 in the soil at each time was read according to the standard curve. The results are shown as follows. Figure 7 、 Figure 8 、 Figure 9 shown.

[0113] Figure 7 Schematic diagram of the adsorption characteristics of the fluorescent products corresponding to the products obtained in Examples 1-3 of the present invention in soil; Figure 8 Schematic diagram of the adsorption characteristics of the fluorescent products corresponding to the products obtained in Examples 4-6 of the present invention in soil; Figure 9 Schematic diagram of the adsorption characteristics of the fluorescent products corresponding to the products obtained in Examples 7-8 and Comparative Example 1 of the present invention in soil.

[0114] Figure 7 、 Figure 8 、 Figure 9 The adsorption amount of the fluorescent products corresponding to Comparative Example 1 and Examples 1-8 in the soil at various times can be seen. It can be seen that as the primary amine salt content in the drug increases, the positive ion concentration increases, the electrostatic adsorption process with the negatively charged test soil is accelerated, and the adsorption rate increases rapidly; when the cationic content exceeds a certain value, the effect of molecular weight changes on the soil adsorption rate begins to become prominent, small molecular weight drugs are more easily desorbed, and the equilibrium adsorption amount decreases.

[0115] 4. Biological toxicity test

[0116] Zebrafish were purchased from Shanghai Feixi Biotechnology Co., Ltd. with a total length of 2 ± 0.5 cm and a weight of 0.2 ± 0.1 g.

[0117] Fish acute oral toxicity test: Referring to "GB / T 31270.12-2014 Laboratory Guidelines for Environmental Safety Assessment of Chemical Pesticides - Part 12: Fish Acute Toxicity Test", a semi-static test method was used to test the acute toxicity of the random-structured poly(acrylamide-methacrylamide primary amine salt) prepared in Comparative Example 1 and Examples 1-8, and the control group benzalkonium chloride in aqueous solution to zebrafish. The specific experimental process is as follows: a series of gradient concentrations are accurately set within the concentration range determined in the pre-experiment, and the step difference is required to be controlled within 2.2 times. Seven zebrafish are placed in each gradient concentration, and at least three groups of samples are repeated for each concentration. During the experiment, the drug solution is replaced regularly every day (the drug solution refers to the poly (acrylamide-methacrylamide primary amine salt) with a random structure prepared in Comparative Example 1 and Examples 1-8 and the benzalkonium chloride aqueous solution of the control group) to ensure that the drug concentration in the acclimation environment remains unchanged. The survival of each group of zebrafish for 96 hours is recorded (when the tail of the fish is lightly touched with a glass rod, no visible movement is determined to be dead), and the 24, 48 and 96 hour median lethal concentration (LC50) of the zebrafish is calculated. 50 ). The test results are shown in Table 1.

[0118] Oral toxicity test after drug adsorption in soil: Different from the above-mentioned acute oral toxicity test for fish, 10 g of fresh soil was added to every 1000 mL of drug solution. At the same time, a group of soil suspension without drugs was set up as a control (the experimental data was valid when all zebrafish in the control group of soil suspension without drugs survived. This control was not listed in Table 1. All zebrafish in this control group survived). After mixing evenly, the mixture was allowed to stand for 12 hours before adding 7 zebrafish for toxicity test. At least 3 groups of samples were repeated for each concentration. During the experiment, the drug solution was changed regularly every day to ensure that the drug concentration in the acclimation environment remained unchanged. The survival of each group of zebrafish was recorded for 96 hours (when the fish tail was touched with a glass rod, no visible movement was determined to be dead), and the 96-hour median lethal concentration (LC50) of zebrafish was calculated. 50S ). The test results are shown in Table 1.

[0119] Table 1

[0120]

[0121]

[0122] As can be seen from Table 1, the oral acute toxicity of the product prepared in Comparative Example 1 of the present invention and the poly(acrylamide-methacrylamide primary amine salt) with random structure prepared in Examples 1-8 to zebrafish is in the range of 1-10 mg / L, which is poisoning. The oral acute toxicity (LC) of the soil-containing turbid solution after mixing with soil to zebrafish is 50S ) are greater than 10 mg / L, which is low toxicity and much higher than the LC of benzalkonium chloride under the same conditions. 50S value.

Claims

1. A poly(acrylamide-methacrylamide primary amine salt) having a random structure, characterized in that Its structural formula is shown in Formula 1: Formula 1, Wherein, m and n are both positive integers, and m:n=2:8 or 3:

7.

2. The method for preparing the poly(acrylamide-methacrylamide primary amine salt) having a random structure according to claim 1, wherein: The following steps are involved: dissolving acryloylethylenediamine hydrochloride monomer, acrylamide monomer, and an initiator in a solvent, and performing a polymerization reaction to obtain the poly(acrylamide-methacrylamide primary amine salt) having a random structure; The initiator is a water-soluble azo substance; The molar ratio of the acryloylethylenediamine hydrochloride monomer to the acrylamide monomer is 2:8 or 3:

7.

3. The preparation method according to claim 2, characterized in that The polymerization reaction is carried out under an inert gas atmosphere.

4. The preparation method according to claim 2, characterized in that The polymerization reaction temperature is 50° C.-80° C.; the polymerization reaction time is 5-8 hours.

5. Use of the poly(acrylamide-methacrylamide primary amine salt) having a random structure according to claim 1 in soil.

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