A method for detecting antibacterial algae adhesion ability

Abstract

The present invention relates to a method for detecting the antibacterial algae adhesion ability, which comprises the following steps: S1, selecting algae: taking a water sample from an environment to be tested, detecting the algae species in the water sample, and selecting an algae with a large growth amount as the target algae; S2, culturing the selected target algae, and after culturing, diluting the target algae to a cell density of 10 5 ~10 7 / ml of algae liquid; S3, respectively, untreated concrete blocks as controls and after brushing or spraying the tested coating on concrete blocks, soaked in algae liquid for cultivation; S4, measure the growth of algae species on the surface of the test blocks every other day, measure and record the results by taking photos or using a chlorophyll fluorescence imager, and characterize by measuring the fluorescence intensity obtained. This detection method is simple to operate, and accurately describes the strength of the antibacterial algae ability through fluorescence values, solving the current problem of difficulty in detecting the distribution of bacteria and algae on the concrete surface and difficulty in accurately describing the antibacterial algae ability of concrete with data.

Description

Technical Field

[0001] The invention relates to a method for detecting antibacterial algae adhesion ability, belonging to the technical field of coating quality detection. Background Art

[0002] At present, the detection method of antibacterial algae adhesion ability in the prior art has the following problems:

[0003] (1) Due to the complex growth of algae in the prior art, the workload of counting the number is large and difficult to achieve.

[0004] (2) Since there is no reference standard in the prior art to describe the adhesion of bacteria and algae, it is impossible to output data, only an apparent concept. Therefore, it is urgent to provide a detection method that can accurately evaluate the ability of antibacterial algae adhesion. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a method for detecting the antibacterial algae adhesion ability, and the present invention solves the problem of accurately evaluating the antibacterial algae adhesion ability of concrete.

[0007] (II) Technical solution

[0008] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0009] A method for detecting the antibacterial algae adhesion ability of concrete comprises the following steps:

[0010] S1. Select algae: Take a water sample from the environment to be tested, detect the algae species in the water sample, and select an algae with a larger growth amount as the target algae;

[0011] S2. Cultivate the selected target algae. After cultivation, dilute the target algae to a cell density of 10 5 ~10 7 / ml of algae liquid;

[0012] S3, respectively, untreated concrete test blocks as a control and the antibacterial algae coating to be tested are brushed or sprayed on the concrete test blocks, and then immersed in algae liquid for cultivation; the culture conditions are the same as the culture of the target algae species in step S2, and the mixture is stirred twice a day to ensure uniformity;

[0013] S4. The growth of algae species on the surface of the test block is measured every other day. The growth condition is measured by taking photos or using a chlorophyll fluorescence imager and the results are recorded. The fluorescence intensity obtained by the measurement is used to characterize the antibacterial algae adhesion ability of the tested coating.

[0014] In the detection method described above, preferably, in step S2, the target algae is Chlorella vulgaris, the culture conditions are shaking speed of 70 rpm, using a 4100K fluorescent tube as the light source, and the light intensity of 35 μmol.m -2 .s -1 , the photoperiod was 10L:14D, the culture temperature was 25±1℃; cultured to the logarithmic growth phase, centrifuged and diluted to a cell density of 10 5 ~10 7 / ml.

[0015] In the detection method as described above, preferably, in step S3, the size of the concrete test block is a square test block of 50 to 150 mm.

[0016] In the detection method as described above, preferably, in step S3, when the algae liquid is added for immersion, the algae liquid only needs to cover half of the height of the test block.

[0017] In the detection method as described above, preferably, in step S4, before testing, the test block is taken out of the algae solution and placed on a square culture dish for 1.5 hours to dry the surface, and then photographed or the chlorophyll fluorescence value of the immersed part of the test block is measured using a chlorophyll fluorescence imager.

[0018] As described above, in the detection method, preferably, in step S4, when the turbidity of the algae solution is too large, that is, the absorbance value of the algae solution at 730nm is ≥1 or obvious death occurs (the chlorophyll concentration, that is, the fluorescence value of the algae solution drops significantly), the test is terminated, otherwise the test continues; then, the surface of the test block is photographed and chlorophyll fluorescence imaging is performed or measured by a chlorophyll fluorescence imager, and the data is recorded.

[0019] As described above, in the detection method, preferably, in step S4, the algae solution needs to maintain a healthy state for at least 6 to 8 days. If the algae solution becomes too turbid (i.e., the absorbance value of the algae solution at 730 nm is ≥ 1) or obvious death occurs after less than 6 days, new algae solution needs to be added to continue culturing until the algae solution becomes too turbid or obvious death occurs, and the test is terminated.

[0020] According to the detection method as described above, preferably, in step S4, when judging the result, the fluorescence value of the tested coating measured at the end of the test is compared with the fluorescence value of the control. If the fluorescence value of the tested coating is less than 50% to 60% of the fluorescence value of the control, it means that the antibacterial algae adhesion performance of the tested coating is good; if the difference between the fluorescence values ​​of the control and the tested coating / the fluorescence value of the control is less than 20%, it means that the antibacterial algae adhesion performance of the tested coating is not good or poor.

[0021] (III) Beneficial effects

[0022] The beneficial effects of the present invention are:

[0023] The present invention provides a method for detecting the antibacterial algae ability, which compares concrete blocks coated with antibacterial algae coating and blank concrete blocks (as a control) to prove that the coating has significant efficacy in resisting the growth of antibacterial algae. The detection method is simple to operate and can accurately express the strength of the antibacterial algae ability through fluorescence values; it solves the current problem of difficulty in detecting the distribution of bacteria and algae on the concrete surface and difficulty in accurately expressing the antibacterial algae ability of concrete with data. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 For algae culture and anti-algae test culture of test pieces;

[0025] Figure 2 The surface conditions of each test block before and after soaking in Chlorella algae liquid;

[0026] Figure 3 This is the result of surface Chlorophyll fluorescence imaging of Chlorella vulgaris. DETAILED DESCRIPTION

[0027] The inventive principle of the present invention:

[0028] 1. Analyze and screen the algae in the target environment to eliminate interference items in the detection;

[0029] 2. Providing algae with a relatively good growth environment can greatly shorten the time required for the test and achieve the test purpose as soon as possible;

[0030] 3. Use mature chlorophyll fluorescence value corresponding detection to scientifically output test data.

[0031] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0032] Example 1

[0033] A method for detecting the antibacterial algae property of an antibacterial algae-attached coating for concrete comprises the following steps:

[0034] S1. Select algae from water samples

[0035] Using the upright microscope method: 1L of water sample plus Lugo's reagent is fixed in a container. After natural sedimentation for 24 hours, the supernatant is sucked out by siphoning and concentrated to 30-50mL. Then 1mL is taken and placed in a blood cell counting plate. The algae with a large number are counted under an upright microscope, and a large number of algae are selected as the target algae. After the test, it was decided to culture Chlorella as the target algae.

[0036] S2. Cultivating selected algae

[0037] Method: The algae were inoculated in BG-11 culture medium in a triangular flask at an OD value of 0.05 at 730 nm and cultured aseptically. The shaking speed was 70 rpm and the light source was 4100K fluorescent tube with a light intensity of 35 μmol.m -2 .s -1 (about 2000 lux), the photoperiod was 10L:14D, and the culture temperature was 25±1℃. The experimental algae were cultured to the logarithmic growth phase, centrifuged at 4000rpm, and resuspended in 1 / 3 BG-11 culture medium to a cell density of 10 6 / ml for later use, such as Figure 1 As shown in the first picture on the left.

[0038] S3. Soak the concrete in algae soaking liquid

[0039] Method: Take the original concrete test blocks (control, without any coating) and the test blocks coated with antibacterial algae coating (test product, the coating can be prepared by mixing 20 parts of sodium silicate, 15 parts of potassium silicate, 2 parts of sodium stearate, 1 part of propylene glycol butyl ether, 0.4 parts of polysiloxane, 3 parts of potassium nitrite, 1 part of PNS, 20 parts of polyvinyl acetate, 2 parts of ultrafine cement powder, 0.7 parts of OIT, 0.7 parts of Diuron and 35 parts of water). The test blocks are all 100mm×100mm×100mm, and are placed in square plastic boxes respectively. They are soaked in the algae solution cultured in step S2, and half of the test blocks are immersed in the algae solution, that is, the height of the test blocks buried by the algae solution is 5cm. The light and temperature conditions are the same as those for the algae culture in S2, and the mixture is stirred twice a day to ensure uniformity. Figure 1 As shown in the middle and first right picture.

[0040] S4. Observe the growth of bacteria and algae

[0041] The growth of algae on the surface of the test block and the growth of the algae solution after the test block is soaked are measured every other day. The growth situation can be recorded by taking pictures or scanning with a chlorophyll fluorescence imager. Before the test, the test block is taken out of the algae solution and placed on a square culture dish for 1.5 hours to dry the surface, and then photographed or measured with a chlorophyll fluorescence imager; at the same time, the total chlorophyll fluorescence intensity or turbidity of the algae solution that has soaked the concrete test block is measured or observed to characterize the growth of the algae solution. The photographic results of the test block are as follows: Figure 2 As shown, it can be seen in the figure that the upper part is exposed in the air and the lower part is immersed in the algae liquid. The two columns on the left are original concrete blocks, and the two columns on the right are concrete blocks coated with paint.

[0042] The chlorophyll fluorescence of algae cells on the surface of the test block was induced by the Kautsky effect program. The test block was dark-treated for 15 minutes before the test, and the light intensity was 40 μmol.m -2 .s -1The orange-red light (620nm) with intensity close to the growth light was irradiated vertically for 30 seconds, and the instrument recorded the minimum fluorescence in the dark and the change of fluorescence over time. Since the fluorescence signal on the surface of the test block was weak, the maximum sensitivity of the instrument was used for signal collection during the test.

[0043] When using a chlorophyll fluorescence imager to characterize and measure the algae liquid that has been immersed in a concrete test block, the excitation wavelength is scanned from 620nm; the chlorophyll specific fluorescence signal is emitted at a wavelength of 695nm-770nm to measure the chlorophyll fluorescence value.

[0044] The experiment was carried out for two consecutive cycles, 0-6 days and 6-12 days. Through observation, it was found that the concentration of the algae solution reached the highest on the 4th day after the test block was soaked, and it began to die on the 5th day. The fluorescence value of the algae solution dropped significantly, and the turbidity of the algae solution at 730nm absorbance value ≥1. In order to observe whether the death of the algae solution was an accidental event, the inventor replaced the test block with a new algae solution after the test on the 6th day. The results showed that the concentration of the algae solution reached the highest on the 10th day, the algae solution began to turn yellow on the 11th day (the 5th day of cycle 2), and the algae solution was almost dead on the 12th day. This shows that the soaking test block itself has a certain killing ability on algae, and the system can only be maintained for no more than 6 days. During the research process, it was found that soaking for 6 days would cause the death of the algae solution. The test block after soaking for 6 days was directly placed in the new algae solution for a second round of soaking. The algae solution also died 6 days after the second round of soaking, with a total of 12 days of data. The results are shown in Table 1.

[0045] If there is no chlorophyll fluorescence imager, the fluorescence value can be obtained by comparing the photographed image with the chlorophyll fluorescence value scale. For some comparisons, see Figure 3 The left column in the figure is the original concrete block of the control, and the right column is the concrete block after applying the antibacterial algae adhesion coating. From top to bottom, it is sorted by days. The result is determined by comparing the chlorophyll fluorescence value of the immersed part of the tested coating and the control.

[0046] Table 1 Chlorophyll fluorescence values ​​of Chlorella on the surface of concrete blocks

[0047]

[0048]

[0049] The detection method is based on the size of the chlorophyll fluorescence value, and the accuracy is determined by the length of time the algae solution is maintained. Generally, the algae solution needs to be maintained in a healthy state for at least 6 to 8 days, that is, the test will only be considered qualified if it is carried out smoothly for more than 6 days, otherwise it is necessary to continue to add new cultured algae solution for testing.

[0050] To verify the performance of the antibacterial algae coating, the surface Chlorella chlorophyll fluorescence value of the immersed part of the original concrete test block (control) not coated with the antibacterial algae coating is measured and compared: if the fluorescence value of the concrete test block coated with the antibacterial algae coating is less than 60% of the fluorescence value of the original concrete test block (control) not coated with the antibacterial algae coating, it means that the antibacterial algae performance of the antibacterial algae coating to be tested is good; if the fluorescence value of the concrete test block coated with the antibacterial algae coating is not much different from the fluorescence value of the original concrete test block (control) not coated with the antibacterial algae coating (the difference between the fluorescence values ​​of the control and the coating to be tested / the fluorescence value of the control is less than 20%), it means that the antibacterial algae performance of the antibacterial algae coating is not good or poor.

[0051] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any person skilled in the art can use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. A method for detecting the antibacterial algae adhesion ability, characterized in that: It includes the following steps: S1. Select algae: Take a water sample from the environment to be tested, detect the algae species in the water sample, and select an algae with a larger growth amount as the target algae; S2. Cultivate the selected target algae. After cultivation, dilute the target algae to a cell density of 10 5 ~10 7 / ml of algae liquid; S3, respectively, untreated concrete test blocks as a control and the antibacterial algae coating to be tested are brushed or sprayed on the concrete test blocks, and then immersed in algae liquid for cultivation; the cultivation conditions are the same as the cultivation of the target algae species in step S2, and the concrete is stirred twice a day to ensure uniformity; S4. The growth of algae on the surface of the test block is measured every other day. The growth is measured by taking pictures or using a chlorophyll fluorescence imager and the results are recorded. The fluorescence intensity obtained by measuring is used to characterize the antibacterial algae adhesion ability of the tested coating. In step S2, the target algae is Chlorella vulgaris, the culture conditions are a shaking speed of 70 rpm, a 4100K fluorescent tube as the light source, and a light intensity of 35 μmol.m -2 .s -1 , the photoperiod was 10L:14D, the culture temperature was 25±1℃; cultured to the logarithmic growth phase, centrifuged and diluted to a cell density of 10 5 ~10 7 / ml; In step S4, before testing, the test block is taken out of the algae solution and placed on a square culture dish for 1.5 hours to dry the surface, and then photographed or the chlorophyll fluorescence value of the immersed part of the test block is measured using a chlorophyll fluorescence imager; When the turbidity of the algae solution is too large, that is, the absorbance value of the algae solution at 730nm is ≥1 or obvious death occurs, the test is terminated, otherwise the test continues; then take a photo of the surface of the test block and perform chlorophyll fluorescence imaging or measure with a chlorophyll fluorescence imager and record the data; The algae solution must be kept in a healthy state for at least 6 to 8 days. If the algae solution becomes too turbid, i.e. the absorbance at 730nm is ≥1 or obvious death occurs, then new algae solution must be added to continue the culture until the algae solution becomes too turbid or obvious death occurs, and the experiment is terminated. When judging the results, the fluorescence value of the tested coating measured at the end of the test is compared with the fluorescence value of the control. If the fluorescence value of the tested coating is less than 50% to 60% of the fluorescence value of the control, it means that the antibacterial algae adhesion performance of the tested coating is good; if the difference between the fluorescence values ​​of the control and the tested coating / the fluorescence value of the control is less than 20%, it means that the antibacterial algae adhesion performance of the tested coating is poor or poor.

2. The detection method according to claim 1, characterized in that In step S3, the size of the concrete test block is a square test block of 50 to 150 mm.

3. The detection method according to claim 1, characterized in that In step S3, when the algae solution is added for soaking, the algae solution should cover half of the height of the test block.

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