Peroxyacetic acid-based composite disinfectant and application thereof in biological membrane removal

Abstract

The invention provides a peroxyacetic acid-based composite disinfectant and an application thereof in biological membrane removal. The peracetic acid-based composite disinfectant provided by the invention comprises peracetic acid with the concentration of 0.1-1%, a surfactant with the concentration of 0.1-5%, a stabilizer with the concentration of 0.1-0.5% and deionized water as a solvent, and the pH value of the peracetic acid-based composite disinfectant is 2.5-4.5. The disinfectant overcomes the defects that traditionally used peracetic acid is high in concentration, high in corrosivity and poor in stability and needs to be prepared before use, solves the problem that a traditional disinfectant is difficult to eradicate a biological membrane, remarkably improves the removal capacity of the disinfectant to the biological membrane after the peracetic acid is compounded with a specific auxiliary raw material, is efficient and convenient, is good in stability, and has a good application prospect. The characteristics of low concentration, low toxicity and low corrosivity are also realized; the adopted raw materials are environment-friendly and easy to decompose after being used, harmful byproducts generated in the disinfection process are effectively reduced, and an efficient, safe and environment-friendly disinfectant is provided for public health safety and environmental protection.

Description

Technical Field

[0001] The present invention belongs to the technical field of chemical disinfectants, and more specifically, relates to a peracetic acid-based composite disinfectant and its application in biofilm removal. Background Art

[0002] The formation of biofilms is a common and thorny problem in key industries such as healthcare, food processing and water treatment. Biofilms are complex structures composed of extracellular polysaccharide matrices secreted by microbial communities. It is a protective growth mode in which bacteria form complex community structures through processes such as adhesion, metabolism and protection, and can form a protective layer on various surfaces, significantly enhancing the resistance of microorganisms to environmental changes and traditional disinfectants. Biofilms have strong adhesion and can firmly attach to various surfaces, such as pipes and instruments. This makes biofilms difficult to remove by conventional cleaning and disinfection methods, and must be removed using professional cleaning agents and appropriate cleaning and disinfection procedures. In addition, bacterial cells in biofilms are more resistant to disinfectants, and ordinary disinfectants often cannot effectively kill these bacteria. In food and beverage production, the presence of biofilms can lead to secondary contamination of products. Since biofilms are difficult to completely remove, even if disinfectants are used, the bacteria in them cannot be effectively killed, resulting in product contamination. The anti-disinfection characteristics of biofilms not only affect food production, but also cause harm to the medical field. In hospitals, more than 80% of bacterial infections are related to biofilms. Biofilm blocks the penetration of antibiotics and sterilization media, leading to bacterial resistance and affecting the disinfection effect of medical devices. Biofilm can lead to biological deposition, which corrodes equipment and affects heat conduction efficiency. In food processing environments, biofilm deposition can damage equipment and reduce production efficiency. Since biofilm is corrosive and difficult to remove, it can also cause secondary pollution, which not only increases the difficulty of cleaning and disinfection, but is also closely related to hospital infections and food safety issues, posing a serious threat to public health and safety.

[0003] The current method of preventing and treating biofilms is to use professional cleaning agents. Due to the adhesion and anti-disinfection characteristics of biofilms, professional cleaning agents must be used and proper cleaning and disinfection procedures must be followed for cleaning. Equipment and pipelines should also be maintained and inspected regularly to detect and remove biofilms in a timely manner to prevent their formation and spread. Alternatively, appropriate disinfectants can be used, and disinfectants that can effectively penetrate biofilms and kill the bacteria therein can be selected to effectively prevent and treat biofilms in the environment and reduce their harm to the environment and industrial production. The use of traditional disinfectants, such as chlorine, hypochlorite, and hydrogen peroxide, although they have certain bactericidal effects, is obviously insufficient in removing biofilms and is highly irritating. Disinfectants that are prone to producing biofilms, such as chlorine-based disinfectants, should also be avoided.

[0004] Peracetic acid disinfectant is a strong oxidant that can quickly kill viruses, bacteria, fungi and spores. It is a broad-spectrum, high-efficiency and environmentally friendly disinfectant. It is mainly used for disinfection of food processing plants, wards, general surfaces, tools, clothing, mushroom houses, scaffolds, etc. Due to the poor stability, easy decomposition and corrosiveness of peracetic acid, it must be diluted and prepared for immediate use; there are also some prepared peracetic acid disinfectants, but they add a large amount of stabilizers, which are costly and unfriendly to the environment, and will begin to decompose after being stored for 2 months. In order to improve the disinfection effect, existing studies will increase the concentration of peracetic acid in the disinfectant. Excessive concentration of peracetic acid will not only cause damage to the skin and objects, but may also cause too fast decomposition or abnormal reactions, and will also have a strong corrosive effect on metal instruments. In addition, since the highly efficient peracetic acid disinfectant must be prepared and used immediately, the operation is troublesome, and it is very easy to decompose if it is not stored properly. It is also very easy to produce harmful byproducts such as acetic acid. Long-term use may lead to environmental pollution and increased microbial resistance. Therefore, there is an urgent need to provide more efficient, low-concentration, safe, and environmentally friendly disinfection products and disinfection solutions that can effectively remove biofilms. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the problems that the existing disinfectants or disinfection methods are difficult to completely remove biofilms and are highly irritating, and the existing peracetic acid disinfectants have poor stability, and to provide a peracetic acid-based composite disinfectant and its application in biofilm removal.

[0006] The first object of the present invention is to provide a peracetic acid-based composite disinfectant.

[0007] A second object of the present invention is to provide an application of a peracetic acid-based composite disinfectant.

[0008] The third object of the present invention is to provide a method for removing biofilm.

[0009] A fourth object of the present invention is to provide a disinfectant product.

[0010] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0011] The invention provides a peracetic acid-based composite disinfectant, comprising: peracetic acid with a concentration of 0.1-1%, a surfactant with a concentration of 0.1-5%, and a stabilizer with a concentration of 0.1-0.5%, the solvent is deionized water, and the pH value of the disinfectant is 2.5-4.5; the surfactant is a nonionic surfactant selected from polyoxyethylene sorbitol esters or polyoxyethylene alcohols; the stabilizer is an organic acid or a salt thereof, selected from one or more of malic acid, citric acid, sodium malate or sodium citrate.

[0012] The disinfectant provided by the present invention has peracetic acid as a main component, and a surfactant and a stabilizer as auxiliary components. The specific raw material ratio can not only improve the stability of peracetic acid, but also improve the permeability, adhesion and decomposition ability of the disinfectant to the biofilm, and also ensure the safety and environmental protection of the disinfection process. The experimental results show that the bactericidal effect of the peracetic acid-based composite disinfectant is very significant, the logarithmic killing value of microorganisms can reach more than 3, and the biofilm can be almost completely removed; and it has good stability. When stored at 54°C for 14 days, the decrease rate of the content of the effective ingredient peracetic acid is ≤6%, and the storage validity period can reach 1 year.

[0013] The core of the present invention lies in the formula design of the peracetic acid-based composite disinfectant, which achieves efficient removal and disinfection of biofilms through precise proportions and component selection. The main component of the disinfectant is peracetic acid, and the concentration of peracetic acid is controlled at 0.1-1%, which not only ensures a strong oxidative disinfection ability, but also controls it at a lower concentration, has weak corrosiveness, and does not need to be prepared immediately before use; a surfactant with a concentration of 0.1-5% is added to the formula, preferably a polyoxyethylene sorbitol ester or polyoxyethylene alcohol non-ionic surfactant, the interaction between the specific surfactant and the peracetic acid is weak, the decomposition of the peracetic acid will not be accelerated, the surfactant can be combined with the hydrophobic region of the protein, the conformation and function of the protein can be changed, and the permeability and adhesion of the disinfectant to the biofilm can be improved, so as to improve the removal effect of the biofilm; the added stabilizer is selected from organic acids or salts thereof, and the concentration is 0.1-0.5%, which can better ensure the maintenance of the stability of the disinfectant, avoid the decomposition of peracetic acid, so as to extend the effective period of the disinfectant and maintain its chemical stability; at the same time, the pH value of the disinfectant system needs to be maintained at 2.5-4.5 to optimize the activity of the peracetic acid. In addition, in order to improve the solubility of peracetic acid and the uniformity of the disinfectant, a solubilizer at a concentration of 0.1-1%, such as a low-toxic alcohol compound, as well as a preservative and a chelating agent, can be added to the formula to further extend the shelf life of the disinfectant and improve its stability.

[0014] Furthermore, the polyoxyethylene sorbitan ester surfactant is selected from polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan distearate or polyoxyethylene sorbitan monooleate; the polyoxyethylene alcohol surfactant is selected from polyoxyethylene lauryl ether or polyethylene glycol.

[0015] Preferably, the pH is adjusted to a value between 2.5 and 4.5 by adding a buffering agent such as phosphate or acetate.

[0016] The formula design of the disinfectant provided by the present invention breaks through tradition. Compared with the use of the traditional surfactant sodium dodecylbenzene sulfonate, the polyoxyethylene sorbitan ester and polyoxyethylene alcohol surfactants selected by the present invention are less irritating to the skin and eyes, can be easily decomposed into harmless substances by microorganisms in the natural environment, and have relatively less pollution to the environment; compared with the commonly used inorganic acids, the organic acid selected as the stabilizer has the advantages of being relatively less irritating to the skin and mucous membranes, being milder, and being easier to be metabolized, conforming to the modern environmental protection concept, etc., and ensuring the safety and environmental protection of the disinfection process.

[0017] Preferably, the disinfectant further comprises a solubilizer at a concentration of 0.1-1%.

[0018] More preferably, the solubilizing agent is selected from ethanol or isopropanol.

[0019] Further, a preservative may be added to the disinfectant to extend the shelf life of the disinfectant and prevent microbial contamination. The selection of the preservative should take into account its low impact on the environment and safety to the human body to ensure the overall environmental protection and safety of the disinfectant. A chelating agent may be further added to complex the metal ions in the water to prevent the degradation of the metal ions to peracetic acid, thereby further improving the stability and disinfection effect of the disinfectant. The selection of the chelating agent should be based on its friendliness to the environment and its low toxicity to the human body.

[0020] Further preferably, the disinfectant further comprises a preservative at a concentration of 0.01-0.1%, such as sodium benzoate and / or potassium sorbate, and a chelating agent at a concentration of 0.05-0.5%, such as ethylenediaminetetraacetic acid and / or its sodium salt.

[0021] The present invention provides a biofilm removal method, which uses the above-mentioned peracetic acid-based composite disinfectant to act on the surface to be treated by direct spraying or immersion, maintaining a contact time of not less than 5 minutes, and then rinsing with clean water to ensure the complete removal of the biofilm.

[0022] Preferably, when removing the biofilm, the contact time can be adjusted to 10-30 minutes according to the thickness and density of the biofilm to ensure the thorough removal of the biofilm while ensuring the efficiency and safety of the disinfection process. The method can also be adapted to different types and degrees of biofilm contamination by adjusting the concentration and contact time of the disinfectant.

[0023] The invention provides application of a peracetic acid-based composite disinfectant in the disinfection of medical equipment, food processing equipment, drinking water and sewage treatment.

[0024] The invention provides application of a peracetic acid-based composite disinfectant in preparing a disinfectant product for removing biofilm.

[0025] The invention provides a disinfection product, which contains the peracetic acid-based composite disinfectant.

[0026] The present invention has the following beneficial effects:

[0027] Compared with the prior art, the peracetic acid-based composite disinfectant provided by the present invention has the following outstanding innovations and advantages: First, the peracetic acid-based composite disinfectant provided by the present invention overcomes the shortcomings of high oxyacetic acid concentration, strong corrosiveness, poor stability, and the need for preparation before use of traditional disinfectants, and has the ability to efficiently remove biofilms. By optimizing the formula of peracetic acid and using specific surfactants, the penetration capacity of the disinfectant is enhanced to achieve efficient removal of biofilms; secondly, by adding specific stabilizers and maintaining specific pH conditions, the stability of peracetic acid can be significantly improved, the optimal active state of peracetic acid is ensured, and the shelf life of the disinfectant is extended. In addition, the raw materials used in the present invention are low-toxic surfactants and organic acid stabilizers, which are milder, more easily metabolized, and easily biodegraded, reducing the toxicity and corrosiveness of the disinfectant, and also reducing the generation of harmful byproducts, making it safer and reducing the impact on the environment.

[0028] At the same time, the disinfectant provided by the present invention also has a wide range of applications, and is suitable for disinfection of medical equipment, cleaning of food processing equipment, drinking water treatment and sewage treatment and other fields, providing a universal and efficient disinfection solution. In summary, the novel peracetic acid-based composite disinfectant provided by the present invention has brought major innovations to the field of disinfectants, not only improving the disinfection efficiency, but also ensuring the safety of use, being able to significantly remove biofilms, and having good environmental protection characteristics, meeting the strict requirements of modern society for disinfection technology, and having important social and economic value. DETAILED DESCRIPTION

[0029] The following specific examples are used to further illustrate the present invention, but the examples do not limit the present invention in any form. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.

[0030] Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0031] Example 1

[0032] In a closed and temperature-controlled container, accurately measure and slowly add the nonionic surfactant polyoxyethylene monooleate sorbitan to deionized water to a concentration of 0.5%, and stir at 300-500rpm for 10 minutes; then add the stabilizer citric acid to a concentration of 0.3%, and continue stirring for 5 minutes. Subsequently, slowly add peracetic acid to a peracetic acid concentration of 0.5% in the system, maintain a constant stirring speed throughout the addition process, and control the addition speed to avoid local oversaturation. Then adjust the system pH, add phosphate as a buffer, and adjust the pH value of the disinfectant to 2.5-3.5 to ensure the optimal activity of peracetic acid.

[0033] Finally, in order to ensure the uniformity and effectiveness of the disinfectant during storage and use, a solubilizer can be added to further improve the solubility and stability of peracetic acid. The solubilizer uses a low-toxic alcohol compound, such as adding solubilizer ethanol, and its concentration is 0.5%. Since peracetic acid is easily decomposed under high temperature and alkaline conditions, the increase in temperature will significantly accelerate the decomposition rate of peracetic acid. In order to ensure the stability of peracetic acid, during the entire preparation process, a pH meter and a thermometer are used to monitor the pH value and temperature of the solution in real time to ensure that the temperature is maintained between 15°C and 25°C and the pH is controlled to be less than 3.5.

[0034] Example 2

[0035] In a closed and temperature-controlled container, accurately measure and slowly add the surfactant polyoxyethylene monooleate sorbitan to deionized water to a concentration of 0.5%, and stir at a speed of 300-500rpm for 10 minutes; then add the stabilizer citric acid to a concentration of 0.5%, and continue stirring for 5 minutes. Subsequently, slowly add peracetic acid to make the peracetic acid concentration in the system reach 0.5%, maintain a constant stirring speed throughout the addition process, and control the addition speed to avoid local supersaturation. Subsequently, adjust the pH of the system, add phosphate as a buffer, and adjust the pH value of the disinfectant to 2.5-3.5. Finally, add solubilizer ethanol at a concentration of 0.5%. During the above-mentioned entire preparation process, use a pH meter and a thermometer to monitor the pH value and temperature of the solution in real time to ensure that the temperature is maintained between 15°C and 25°C and the pH is controlled to be less than 3.5.

[0036] Example 3

[0037] In a closed and temperature-controlled container, accurately measure and slowly add the surfactant polyoxyethylene monooleate sorbitan to deionized water to a concentration of 0.5%, and stir at a speed of 300-500rpm for 10 minutes; then add the stabilizer citric acid to a concentration of 0.3%, and continue stirring for 5 minutes. Subsequently, slowly add peracetic acid to make the peracetic acid concentration in the system reach 0.3%, maintain a constant stirring speed throughout the addition process, and control the addition speed to avoid local supersaturation. Subsequently, adjust the pH of the system, add phosphate as a buffer, and adjust the pH value of the disinfectant to 2.5-3.5. Finally, add solubilizer ethanol at a concentration of 0.5%. During the above-mentioned entire preparation process, use a pH meter and a thermometer to monitor the pH value and temperature of the solution in real time to ensure that the temperature is maintained between 15°C and 25°C and the pH is controlled to be less than 3.5.

[0038] Example 4

[0039] In a closed and temperature-controlled container, accurately measure and slowly add the surfactant polyoxyethylene monooleate sorbitan to deionized water to a concentration of 0.1%, and stir at a speed of 300-500rpm for 10 minutes; then add the stabilizer citric acid to a concentration of 0.3%, and continue stirring for 5 minutes. Subsequently, slowly add peracetic acid to make the peracetic acid concentration in the system reach 0.3%, maintain a constant stirring speed throughout the addition process, and control the addition speed to avoid local supersaturation. Subsequently, adjust the pH of the system, add phosphate as a buffer, and adjust the pH value of the disinfectant to 2.5-3.5. Finally, add solubilizer ethanol at a concentration of 0.5%. During the entire preparation process above, use a pH meter and a thermometer to monitor the pH value and temperature of the solution in real time to ensure that the temperature is maintained between 15°C and 25°C and the pH is controlled to be less than 3.5.

[0040] Example 5

[0041] In a closed and temperature-controlled container, accurately measure and slowly add the surfactant polyoxyethylene distearate sorbitan to deionized water to a concentration of 1.0%, and stir at a speed of 300-500rpm for 10 minutes; then add the stabilizer malic acid to a concentration of 0.1%, and continue stirring for 5 minutes. Subsequently, slowly add peracetic acid to make the peracetic acid concentration in the system reach 0.1%, maintain a constant stirring speed throughout the addition process, and control the addition speed to avoid local supersaturation. Subsequently, adjust the pH of the system, add phosphate as a buffer, and adjust the pH value of the disinfectant to 2.5-3.5. Finally, add solubilizer ethanol at a concentration of 0.1%. During the entire preparation process above, use a pH meter and a thermometer to monitor the pH value and temperature of the solution in real time to ensure that the temperature is maintained between 15°C and 25°C and the pH is controlled to be less than 3.5.

[0042] Example 6

[0043] In a closed and temperature-controlled container, accurately measure and slowly add the surfactant polyoxyethylene monooleate sorbitan to deionized water to a concentration of 5.0%, and stir at a speed of 300-500rpm for 10 minutes; then add the stabilizer sodium malate to a concentration of 0.5%, and continue stirring for 5 minutes. Subsequently, slowly add peracetic acid to make the peracetic acid concentration in the system reach 1.0%, maintain a constant stirring speed throughout the addition process, and control the addition speed to avoid local supersaturation. Subsequently, adjust the pH of the system, add phosphate as a buffer, and adjust the pH value of the disinfectant to 2.5-3.5. Finally, add solubilizer ethanol at a concentration of 1.0%. During the above-mentioned entire preparation process, use a pH meter and a thermometer to monitor the pH value and temperature of the solution in real time to ensure that the temperature is maintained between 15°C and 25°C and the pH is controlled to be less than 3.5.

[0044] Example 7

[0045] In a closed and temperature-controlled container, accurately measure and slowly add polyoxyethylene alcohol surfactant (polyoxyethylene lauryl ether or polyethylene glycol) to deionized water to a concentration of 0.5%, and stir at a speed of 300-500rpm for 10 minutes; then add stabilizer sodium citrate to a concentration of 0.3%, and continue stirring for 5 minutes. Subsequently, slowly add peracetic acid to make the peracetic acid concentration in the system reach 0.3%, maintain a constant stirring speed during the entire addition process, and control the addition speed to avoid local supersaturation. Subsequently adjust the system pH, add acetate to adjust the pH value of the disinfectant to 2.5-3.5. Finally, add solubilizer isopropanol at a concentration of 0.5%.

[0046] Then, a common preservative in the art, such as sodium benzoate and / or potassium sorbate, may be added to the disinfectant at a concentration of 0.01-0.1% to extend the shelf life of the disinfectant and prevent microbial contamination. A common chelating agent in the art, such as ethylenediaminetetraacetic acid and / or its sodium salt, may be added at a concentration of 0.05-0.5% to complex metal ions in water and prevent the degradation of peracetic acid by metal ions, thereby improving the stability and disinfection effect of the disinfectant. During the entire preparation process, a pH meter and a thermometer are used to monitor the pH value and temperature of the solution in real time.

[0047] Comparative Example 1

[0048] The preparation method of the disinfectant in this comparative example is the same as that in Example 3, the only difference being that the surfactant is replaced by sodium dodecylbenzene sulfonate.

[0049] Comparative Example 2

[0050] The preparation method of the disinfectant in this comparative example is the same as that in Example 3, with the only difference being that the stabilizer is replaced by sodium pyrophosphate.

[0051] Comparative Example 3

[0052] The preparation method of the disinfectant in this comparative example is the same as that in Example 3, except that it does not contain a surfactant.

[0053] Comparative Example 4

[0054] The preparation method of this comparative example is the same as that of Example 3, the only difference being that no stabilizer is included.

[0055] Comparative Example 5 Traditional Disinfectant

[0056] A commercially available hypochlorous acid disinfectant (effective chlorine content: 270 mg / L, pH 4.52) was used.

[0057] Comparative Example 6 Traditional Disinfectant

[0058] A commercially available hydrogen peroxide disinfectant (hydrogen peroxide content: 7.89%, pH 3.74) was used.

[0059] Comparative Example 7 Traditional Disinfectant

[0060] Use commercially available peracetic acid disinfectant (containing A and B agents, which must be stored separately. Mix A+B agents for 24 hours before use and then dilute at 1:50. Peracetic acid hydrogen content: 15.2%, pH 0.18).

[0061] Test Case 1: Safety Assessment

[0062] The safety of the disinfectant prepared in the above-mentioned Examples 1-4 and Comparative Examples 1-4 was evaluated. The safety evaluation method was in accordance with the method in the Technical Specification for Disinfection, and the toxicity and corrosivity of the disinfectant were comprehensively evaluated. The safety of the disinfectant in practical applications was ensured by standardized testing methods such as a complete skin irritation test and a metal corrosion test. The experimental animals for the complete skin irritation test were New Zealand rabbits, and a complete skin irritation test was performed using the original disinfectant solution. At the end of the test, the scores were scored according to Table 2-11 in the Technical Specification for Disinfection (2002 Edition), and the skin irritation intensity was graded according to Table 2-12.

[0063] The results of the skin irritation test showed that the average maximum score at each time point of the one-time skin irritation test on New Zealand rabbits of the disinfectant stock solutions of Examples 1-4 and Comparative Examples 1-4 was 0, indicating that the disinfectant stock solutions were non-irritating.

[0064] Metal corrosion detection, according to each metal sheet needs to be immersed in 200mL disinfectant stock solution, soaked for 72h at one time, the corrosion rate R (mm / a) of the disinfectant metal is calculated and the corrosion grade is evaluated according to the "Technical Specification for Disinfection". The results are shown in Table 1 below, showing that the higher the concentration of peracetic acid, the greater the corrosion to the metal, the faster the corrosion rate, and the more obvious the corrosion to copper; while in Example 3-4, the corrosion rate to the metal is slow, the corrosion grade is low, and it has better safety than Example 1-2. The corrosion degree of the peracetic acid disinfectant prepared by Example 3-4 and Comparative Example 1-4 is consistent, showing that the corrosion grade of the disinfectant is mainly affected by the concentration of peracetic acid, and the higher the concentration of peracetic acid in the existing disinfectant (Comparative Example 7), the greater the corrosion to the metal.

[0065] Table 1 Metal corrosion test results

[0066]

[0067]

[0068] Test Case 2: Stability Evaluation

[0069] The disinfectants prepared in Examples 1-4 and Comparative Examples 1-4 and 7 were stored at 54° C. for 14 days, and tested according to the method in the Technical Specification for Disinfection to determine the change in the peracetic acid content and evaluate its stability.

[0070] The test results are shown in Table 2, which show that after the peracetic acid disinfectant prepared by the present invention is stored in a 54°C constant temperature box for 14 days, the decrease rate of the effective ingredient peracetic acid content in Examples 2-4 is ≤6%, and the storage validity period can be up to 1 year; in Example 1, the concentration of the stabilizer is low, and the decrease rate of the peracetic acid content is higher than that of Example 2. In Comparative Example 1, the commonly used anionic surfactant reacts with peracetic acid, making the peroxy bond in the peracetic acid molecule more easily broken, thereby accelerating the decomposition of peracetic acid, so its peracetic acid content decrease rate is higher than that of Examples 2-4 of the present invention. The interaction between the nonionic surfactant used in the present invention and peracetic acid is weak, and the decomposition of peracetic acid will not be accelerated.

[0071] In Comparative Example 2, sodium pyrophosphate, a common stabilizer, was used, and the reduction rate of peracetic acid content was 14.8%, which was worse than that of Example 1; the reduction rate of peracetic acid content without stabilizer in Comparative Example 4 was the highest, followed by Comparative Example 3, which showed that the disinfectant prepared by the present invention can improve the stability of peracetic acid, and its effect is better than that of using the stabilizer sodium pyrophosphate. Comparative Example 7 uses commercially available peracetic acid disinfectant, which needs to be prepared and used immediately. After the freshly prepared peracetic acid disinfectant is placed at 54°C for one day, peracetic acid will begin to decompose, and its stability is poor.

[0072] Table 2 Stability test results

[0073]

[0074] Test Example 3 Biofilm Removal Effect

[0075] The present invention uses Pseudomonas aeruginosa ATCC15442 and Staphylococcus aureus ATCC6538 to test the above-mentioned Examples 1-4 and Comparative Examples 1-7, and refers to the well plate culture method of T / CI011-2021 "Technical Guide for Cultivation, Observation and Drug Resistance Evaluation of Bacterial Biofilm". Specifically, take an appropriate amount of activated bacteria and inoculate them in LB liquid culture medium, culture at 36°C for 24 hours, and adjust the bacterial solution concentration to 1×10 7 CFU / mL~5×10 7 CFU / mL, inoculate the bacterial solution into a 24-well plate, and the inoculation volume of each well plate is 1mL. The culture medium is replaced every 24 hours. After 5 days of static culture at 36℃, the biofilm is washed with 1mL of PBS, and washed twice in total; add 2mL of disinfectant, absorb the disinfectant after 5 minutes, add 1mL of disinfectant and qualified neutralizer, seal the well plate with a breathable sealing film, use an ultrasonic water bath, at 40KHz, add ice in the water bath and shake for 10 minutes. After ultrasound, count the live bacteria in the wells, and use the diluent instead of the disinfectant as the positive control group to obtain the biofilm removal effect. The biofilm killing logarithm calculation formula is as follows:

[0076] Killing logarithm = logarithm of live bacteria concentration in control group - logarithm of live bacteria concentration in test group

[0077] At the same time, on-site test bacteria quantitative detection is carried out, specifically testing certain medical equipment, food processing tools, water pipes, etc. The specific disinfection steps are as follows:

[0078] (1) Pretreatment stage: First, the target disinfection surface is thoroughly pretreated to remove all visible contaminants and loose biofilms, providing a clean surface for the contact and action of the disinfectant.

[0079] (2) Application of disinfectant: Spray the disinfectant precisely prepared according to the above embodiment evenly on the surface to be disinfected, or completely immerse the items to be disinfected in the disinfectant to ensure that all areas to be disinfected are in full contact with the disinfectant.

[0080] (3) Contact time: The time the disinfectant is in contact with the surface to be disinfected. Generally, the contact time for biofilms is set at 10 minutes. For biofilms that are more difficult to remove, the contact time can be appropriately extended to 20 minutes based on actual conditions to ensure the disinfection effect.

[0081] (4) Rinse and post-treatment: After the contact time is over, rinse the disinfected surface or object thoroughly with clean water to remove all residual disinfectant and biofilm decomposition products. Then dry the disinfected objects appropriately and perform subsequent cleaning or maintenance work as needed.

[0082] Before pretreatment and after rinsing, the disinfected surface was sampled and cultured using the surface sampling method and plate counting method, and the disinfection effect was evaluated by comparing the changes in bacterial counts before and after disinfection.

[0083] The test results of the simulated biofilm removal rate test and the field test evaluation are shown in Table 3 below. The results show that the biofilm removal effect of the peracetic acid disinfectant of Examples 1-4 of the present invention is better than that of the commercially available disinfection products of Comparative Examples 5-7 and Comparative Examples 1-4, and the logarithmic killing value of microorganisms can reach more than 4, and the biofilm can be almost completely removed. Among them, Examples 1-3 have the best effect and have a significant biofilm removal effect.

[0084] The nonionic surfactant polyoxyethylene monooleate sorbitan used in the present invention can bind to the hydrophobic region of the protein, change the conformation and function of the protein, and to a certain extent can change the fluidity and permeability of the biofilm, can improve the permeability and adhesion of the disinfectant to the biofilm, has a good cleaning effect, and can further improve the biofilm removal effect. Therefore, in Comparative Example 4, the concentration of the surfactant is reduced, and the removal effect of the biofilm will be weakened. In Comparative Example 1, the surfactant sodium dodecyl sulfate reacts with peracetic acid, accelerates the decomposition of peracetic acid, and affects the effect of peracetic acid.

[0085] Table 3 Biofilm removal effect test results

[0086]

[0087]

[0088] Note: The killing logarithmic effect in the table differs by 1, which means the order of magnitude is ten times.

[0089] In summary, the present invention innovatively develops a new type of peracetic acid-based composite disinfectant, aiming to solve the problem of biofilm that is difficult to eradicate with traditional disinfection methods. The disinfectant provided by the present invention has a lower concentration of peracetic acid than traditional disinfectants, is less corrosive, does not need to be prepared before use, will not degrade and inactivate, and maintains its pH stability by combining peracetic acid with selected surfactants and stabilizers, which can significantly improve the ability to remove biofilms. The laboratory biofilm removal test and field application results have confirmed the excellent effect of the peracetic acid-based composite disinfectant provided by the present invention in removing biofilms formed by pathogenic bacteria such as Pseudomonas aeruginosa and Staphylococcus aureus. In addition, the disinfectant provided by the present invention is not only efficient, but also has low concentration, low toxicity and low corrosiveness, which greatly reduces the potential risks to human health and the environment. In addition, its formula is environmentally friendly, ensuring easy decomposition after use, reducing the impact on the environment, and effectively avoiding harmful byproducts produced during the disinfection process. The disinfectant provided by the present invention can be widely used in multiple fields such as medical equipment disinfection, food processing equipment cleaning, drinking water and sewage treatment, and provides an innovative, efficient, safe and environmentally friendly disinfection option for public health safety and environmental protection.

[0090] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A peracetic acid-based composite disinfectant, characterized in that: The disinfectant comprises: peracetic acid with a concentration of 0.1-1%, a surfactant with a concentration of 0.1-5%, a stabilizer with a concentration of 0.1-0.5%, the solvent is deionized water, and the pH value of the disinfectant is 2.5-4.5; The surfactant is a nonionic surfactant selected from polyoxyethylene sorbitan esters or polyoxyethylene alcohol surfactants; The stabilizer is an organic acid or a salt thereof, selected from one or more of malic acid, citric acid, sodium malate or sodium citrate.

2. The peracetic acid-based composite disinfectant according to claim 1, characterized in that: The polyoxyethylene sorbitan ester surfactant is selected from polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan distearate or polyoxyethylene sorbitan monooleate; the polyoxyethylene alcohol surfactant is selected from polyoxyethylene lauryl ether or polyethylene glycol.

3. The peracetic acid-based composite disinfectant according to claim 1, characterized in that: The disinfectant also contains a solubilizer with a concentration of 0.1-1%.

4. The peracetic acid-based composite disinfectant according to claim 3, characterized in that: The solubilizing agent is selected from ethanol or isopropanol.

5. The peracetic acid-based composite disinfectant according to claim 1, characterized in that: The disinfectant also contains an antiseptic with a concentration of 0.01-0.1% and a chelating agent with a concentration of 0.05-0.5%.

6. A method for removing biofilm, characterized in that: The peracetic acid-based composite disinfectant according to any one of claims 1 to 5 is directly sprayed or immersed on the surface to be treated, and the contact time is maintained for not less than 5 minutes, and then cleaned to ensure the complete removal of the biofilm.

7. Use of the peracetic acid-based composite disinfectant according to any one of claims 1 to 5 in the disinfection of medical equipment, food processing equipment, drinking water or sewage treatment.

8. Use of the peracetic acid-based composite disinfectant according to any one of claims 1 to 5 in removing biofilm or in preparing a disinfectant product for removing biofilm.

9. A disinfection product, characterized in that: A peracetic acid-based composite disinfectant comprising the peracetic acid-based composite disinfectant according to any one of claims 1 to 5.

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