A reversible enzymatic protective agent for bone cultural relics and its use method and application

Abstract

The invention discloses a reversible enzymatic protective agent for bone cultural relics and a method for using the same and an application thereof, and belongs to the technical field of bone cultural relic protection. The protective agent provided by the invention can quickly form a protective film on the surface of the bone cultural relic, and the fastest time is 9 minutes, and can effectively fill the crisp gaps on the surface of the bone cultural relic. The hardness, porosity and compressive strength of the bone cultural relic protected by the protective agent provided by the invention are significantly improved; the protective agent provided can be thoroughly washed off by spraying a 50±5°C, 1% ethylene glycol aqueous solution, then rinsing with running water, and lightly brushing with a soft brush to assist, and the bone cultural relic after washing off the protective agent has no obvious change from the surface of the cultural relic before protection / reinforcement by the protective agent, and has strong reversibility; the components of the protective agent and the eluent are all non-toxic or low-toxic preparations, and there is no safety hazard to the health of bone cultural relic protectors and visitors. It is green and environmentally friendly, simple to operate, and suitable for the protection of bone cultural relics.

Description

Technical Field

[0001] The invention relates to the technical field of bone cultural relics protection, and in particular to a reversible enzymatic protective agent for bone cultural relics and a use method and application thereof. Background Art

[0002] At present, the operation used for the protection of bone cultural relics is mostly in-situ protection, that is, the surface of bone cultural relics is cleaned immediately after being excavated, and protective agents are used to reinforce them, and exhibition halls are built on the original site or moved to museums for display. At present, scholars have developed a variety of protective agents and tried to use them in the field of bone cultural relics protection. The relevant protective agents mainly include organic material protective agents, inorganic material protective agents and organic-inorganic composite material protective agents.

[0003] Among them, organic material protective agents are currently widely recognized. The common disadvantages of commonly used organic material protective agents are poor reversibility, high toxicity, poor film-forming properties, and potential safety hazards, which limit their scope of application. For example, acrylic resins are brittle and have poor water resistance; epoxy resins are too viscous, and fragile bone cultural relics cannot withstand such high pressure; silicone or modified silicone materials are easy to flow and difficult to solidify, and must be used in conjunction with other auxiliary materials. At the same time, organic material protective agents also require the use of a large amount of organic reagents during use, which have serious problems such as high toxicity, unfriendly environment, poor operator safety, and health hazards to visitors. Therefore, foreign countries have begun to gradually restrict the use of related organic material protective agents.

[0004] The International Charter for the Conservation and Restoration of Monuments and Sites (Venice Charter), promulgated in 1964, is an important standard followed by cultural relics protection experts and heritage managers around the world. It stipulates that the "reversibility" principle is one of the basic principles of cultural relics protection and restoration. The poor reversibility of organic material protective agents means that after various types of organic material protective agents are applied to bone cultural relics by spraying or dripping, the curing effect of the organic material protective agents will cause the bone cultural relics and the bone cultural relics and the display soil to form blocks while strengthening the bone cultural relics. Moreover, the various types of organic material protective agents after curing are difficult to remove, and it is difficult for bone cultural relics to be restored to their original bone state. The disadvantage of poor reversibility of organic material protective agents limits the re-collection of samples of bone cultural relics reinforced by this method and subsequent in-depth morphological research.

[0005] The high toxicity of organic material protective agents means that organic material protective agents often use chloroform, toluene, acetone and other reagents as solvents. For the operator's body, mild contact can cause conjunctival congestion and skin edema, while long-term contact can cause embryotoxicity, teratogenicity, liver necrosis or liver cancer and many other diseases. For archaeological sites that have received extremely high attention and need to be displayed to the public for a long time, such as the Lajia Ruins in Minhe, Qinghai, the Liuwan Cemetery in Ledu, Qinghai, and the Hamin Mangha Ruins in Inner Mongolia, organic material protective agents are also very harmful to the body of visitors: organic material solvents (chloroform, toluene, acetone, etc.) can enter the visitor's body through inhalation or absorption through the skin, irritating the mucous membrane and anesthetizing the central nervous system, causing dizziness, headache, vomiting, limb weakness, confusion and other symptoms.

[0006] Poor film-forming properties of organic material protective agents refer to the inability of organic material protective agents to maintain hardness while having good ductility. During long-term protection, they are prone to cracking, discoloration, etc. due to oxidation or changes in environmental humidity, which leads to secondary damage to bone cultural relics during storage. This phenomenon also reflects that this type of protective agent cannot meet actual needs. The safety hazard of organic material protective agents refers to the fact that the organic solvents used in organic material protective agents are highly flammable, and there are serious explosion hazards during the implementation of bone cultural relics protection operations.

[0007] Microbial mineralization material protective agents are also being tried in the field of bone cultural relics protection, but they are currently mainly in the research stage. Among them, microbial induced calcium carbonate mineralization (MICP) has been reported the most, that is, the urease in the microorganisms hydrolyzes urea to induce carbon dioxide and calcium ions in the air to produce calcium carbonate precipitation to play a protective role. Bacillus pasteurianus can produce urease and ultimately induce the production of calcium carbonate. It is a microorganism with excellent mineralization effect that is used in the fields of slope stability, soil anti-liquefaction, coastal anti-erosion, foundation reinforcement, etc. However, the cultivation cost of Bacillus pasteurianus is high, the growth controllability is poor, the enzyme production conditions are highly dependent on the environment, and Bacillus pasteurianus has antagonistic effects with the microorganisms of bone cultural relics themselves, which leads to significant differences in the number of bacterial distribution and growth state, and then leads to uneven distribution of mineralization products (usually calcium carbonate) as protective materials, which makes the controllability and repeatability of microbial mineralization material protective agents poor during implementation, limiting their wide application. Summary of the invention

[0008] The purpose of the present invention is to provide a reversible enzymatic protective agent for bone cultural relics and a use method and application thereof. The protective agent provided has the advantages of rapid film formation, obvious reinforcement effect on bone cultural relics, good reversibility and no complete hidden dangers.

[0009] To achieve the above purpose, the present invention provides a reversible enzymatic protective agent for bone cultural relics, including a Ra component and a Rb component. The Ra component is an aqueous solution of an enzyme and a basement membrane, and the Rb component is an aqueous solution of urea, sodium β-glycerophosphate, and a calcium compound.

[0010] Preferably, the enzyme is a mixture of urease and alkaline phosphatase, the amount of urease is 30-100 IU / LRa component, and the amount of alkaline phosphatase is 30-100 IU / LRa component.

[0011] Preferably, the basement membrane is composed of gelatin and sodium alginate, the amount of gelatin is 30-70 g / L, and the amount of sodium alginate is 45-100 g / L.

[0012] Preferably, the calcium compound is one of calcium chloride, calcium acetate and calcium lactate.

[0013] Preferably, the dosage of urea is 8-12 g / L, the dosage of sodium β-glycerophosphate is 20-35 g / L, and the dosage of calcium compound is 50-100 g / L.

[0014] Preferably, a 1% ethylene glycol aqueous solution is used as the removing agent, and the protective agent can be removed by flushing, soaking or light brushing with a soft brush.

[0015] A method for using the above-mentioned reversible enzymatic protective agent for bone cultural relics comprises the following steps:

[0016] S1. Dissolve gelatin and sodium alginate in water, then add enzyme and stir to obtain Ra;

[0017] S2, dissolving urea, sodium β-glycerophosphate and calcium compounds in water to obtain Rb;

[0018] S3. Make the prepared Ra solution adhere to the part of the bone cultural relic to be protected by brushing or spraying. After standing for 10 minutes, apply Rb to the corresponding part of the bone cultural relic by spot coating or spraying, and dry naturally / freeze dry / blow dry with a fan.

[0019] A use of the reversible enzymatic protective agent for bone cultural relics as described above in the protection of bone cultural relics.

[0020] The main components of the protective agent provided by the present invention include three types of components: enzymes, substrates and basement membranes, wherein the enzymes include urease and alkaline phosphatase; the substrates include sodium β-glycerophosphate, calcium sources (calcium chloride, calcium acetate, calcium lactate), and urea; and the basement membrane includes gelatin, chitosan, and sodium alginate. Among them, gelatin (GB 6783-2013), chitosan (GB 29941-2013), sodium alginate (GB1886.243-2016), calcium chloride (GB 1886.45-2016), calcium acetate (GB 1903.15-2016), and calcium lactate (GB1886.21-2016) are all food additives or food nutrition enhancers with high safety. Sodium β-glycerophosphate, urease and alkaline phosphatase are highly safe and are not included in the Catalogue of Hazardous Chemicals in China (2022 Adjusted Version). They are also not included in the hazard categories of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS).

[0021] Therefore, the present invention provides a reversible enzymatic protective agent for bone cultural relics and its use method and application, and its specific technical effects are as follows:

[0022] (1) The protective agent provided by the present invention can quickly form a protective film on the surface of bone cultural relics, with the fastest time being 9 minutes, and can effectively fill the crisp gaps on the surface of bone cultural relics. The hardness, porosity and compressive strength of bone cultural relics protected by the protective agent provided by the present invention are significantly improved;

[0023] (2) The protective agent provided by the present invention can be thoroughly washed off by spraying a 50±5°C, 1% ethylene glycol aqueous solution, then rinsing with running water and brushing with a soft brush. The surface of the bone cultural relics after washing off the protective agent is not significantly different from that before protection / reinforcement with the protective agent, and the protective agent has strong reversibility.

[0024] (3) The components of the protective agent and the eluent provided by the present invention are all non-toxic or low-toxic preparations, which pose no potential safety hazard to the health of bone cultural relics protectors and visitors. They are green and environmentally friendly, easy to operate, and suitable for the protection of bone cultural relics.

[0025] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0027] Figure 1 These are photos of bone cultural relics before spraying the protective agent in the second test of the present invention (A), after spraying the protective agent prepared in Example 2 (B), and after eluting with the eluent (C);

[0028] Figure 2 It is the result of spectrum analysis of the protective film formed after spraying the protective agent in the third test of the present invention. DETAILED DESCRIPTION

[0029] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0030] In order to make the purpose, technical scheme and advantages of the present application clearer, more thorough and more complete, the technical scheme of the present invention is clearly and completely described below through the accompanying drawings and examples. The following detailed descriptions are all descriptions of the embodiments, and are intended to provide further detailed descriptions of the present invention. Unless otherwise specified, all technical terms used in the present invention have the same meaning as those generally understood by those skilled in the art to which the present application belongs.

[0031] The instruments, equipment, reagents and materials used in the examples were all obtained through commercial channels.

[0032] Embodiment 1

[0033] A reversible enzymatic protective agent for bone cultural relics is prepared as follows:

[0034] (1) Prepare 100 mL of Ra solution by accurately weighing 3 g of gelatin and 6.5 g of sodium alginate, adding 100 mL of deionized water, stirring until completely dissolved, adding 10 IU of urease and 5 IU of alkaline phosphatase, and stirring to mix well.

[0035] (2) Prepare 100 mL of Rb solution by accurately weighing 1.2 g of urea, 2 g of sodium β-glycerophosphate, and 5 g of calcium chloride, adding them to 100 mL of deionized water, and stirring until they are completely dissolved.

[0036] (3) Ra is applied to the part of the bone cultural relic to be protected by brushing. After standing for 10 minutes, Rb is then applied to the part of the bone cultural relic to be protected by spraying and allowed to dry naturally.

[0037] Embodiment 2

[0038] A reversible enzymatic protective agent for bone cultural relics was prepared by the same method as in Example 1, except that the components in step (1) were 5 IU urease, 10 IU alkaline phosphatase, 5 g gelatin and 8.5 g sodium alginate;

[0039] The components in (2) are: 0.8 g urea, 3.5 g sodium β-glycerophosphate, and 8 g calcium chloride.

[0040] In (3), Ra is attached to the part of the bone cultural relic to be protected by spraying, and after standing for 60 minutes, Rb is directionally applied to the corresponding part of the bone cultural relic by spot coating, and then freeze-dried.

[0041] Embodiment 3

[0042] A reversible enzymatic protective agent for bone cultural relics was prepared by the same method as in Example 1, except that the components in step (1) were 10 IU urease, 10 IU alkaline phosphatase, 7 g gelatin and 10 g sodium alginate;

[0043] (2) The components are 1.2 g urea, 3.5 g sodium β-glycerophosphate, and 10 g calcium chloride;

[0044] In (3), Ra is attached to the part of the bone cultural relic to be protected by soaking, and after being taken out and left to stand for 60 minutes, Rb is directionally applied to the corresponding part of the bone cultural relic by spraying, and then blown dry by a fan.

[0045] Embodiment 4

[0046] A reversible enzymatic protective agent for bone cultural relics was prepared by the same method as in Example 1, except that the components in step (1) were 3 IU urease, 3 IU alkaline phosphatase, 3 g gelatin and 4.5 g sodium alginate;

[0047] (2) The components are 0.8 g urea, 2.0 g sodium β-glycerophosphate, and 10 g calcium chloride;

[0048] In (3), Ra is attached to the part of the bone cultural relic to be protected by soaking, and after being taken out and left to stand for 20 minutes, Rb is applied to the corresponding part of the bone cultural relic by spraying, and then dried naturally.

[0049] Comparative Example 1

[0050] A method for preparing an enzymatic protective agent for bone cultural relics is as follows:

[0051] (1) Prepare solution I by adding 10 IU of urease and 5 IU of alkaline phosphatase into 100 mL of deionized water and stirring to mix.

[0052] (2) Prepare solution II. Accurately weigh 1.2 g urea, 2 g sodium β-glycerophosphate, and 5 g calcium chloride, add them to 100 mL deionized water, and stir until they are completely dissolved. This is referred to as comparative protective agent 1.

[0053] Comparative Example 2

[0054] A bone cultural relic enzymatic protective agent was prepared in the same manner as in Comparative Example 1, except that:

[0055] The components in step (1) are 5 IU of urease, 10 IU of alkaline phosphatase, 5 g of gelatin and 8.5 g of sodium alginate;

[0056] The components in (2) are: 0.8 g urea, 3.5 g sodium β-glycerophosphate, and 8 g calcium chloride. It is recorded as comparative protective agent 2.

[0057] Comparative Example 3

[0058] A protective agent was prepared according to the protective agent formula described in Example 1 of the authorized Chinese invention patent with publication number CN104152046A - an ancient bone resource protective agent, and was recorded as comparative protective agent 3.

[0059] Comparative Example 4

[0060] A protective agent was prepared according to the protective agent formula described in Example 4 of the authorized Chinese invention patent with publication number CN104152046A - an ancient bone resource protective agent, and was recorded as comparative protective agent 4.

[0061] Comparative Example 5

[0062] A protective agent was prepared according to the protective agent formula described in Example 8 of the authorized Chinese invention patent with publication number CN104152046A - an ancient bone resource protective agent, and was recorded as comparative protective agent 5.

[0063] Experimental Test 1

[0064] The film-forming properties of the protective agents prepared in Example 1, Example 2, and Comparative Examples 1 to 5 were measured as follows:

[0065] Under the same experimental environment conditions at room temperature and in the dark, the protective agents prepared in Example 1, Example 2, and Comparative Examples 1 to 5 were poured into a quartz dish of 12.5 mm × 12.5 mm × 45 mm, and the timing was started. The quartz dish was gently shaken every 1 minute to check the flow of the protective agent. When it did not flow after being inverted for 30 seconds, it was determined that a protective film was formed, and the timing was stopped at the same time. The film-forming properties of the above protective agents were compared by comparing the time of protective film formation. The results are shown in Table 1.

[0066] Table 1

[0067] Recipe number Film forming time (min) Protective agent 1 9min Protective agent 2 14min Comparative protective agent 1 109min Comparative Protective Agent 2 113min Comparative protective agent 3 32min Comparative Protective Agent 4 44min Comparative protective agent 5 31min

[0068] As can be seen from Table 1, the film-forming time of the comparative protective agent 1 and the comparative protective agent 2 is much longer than that of the protective agent 1 and the protective agent 2 prepared in Examples 1 and 2 of the present invention, proving that the presence of the base film component in the present invention can indeed effectively reduce the film-forming time. At the same time, the film-forming time of the protective agent prepared in Examples 1 and 2 of the present invention is significantly shorter than that of the protective agent prepared by the preparation method (Comparative Examples 3 to 5) in the authorized similar patent (CN104152046A—An ancient bone resource protective agent), which can greatly speed up the progress of the protection work for bone cultural relics.

[0069] Experimental Test 2

[0070] The reversibility of the bone cultural relics protective agent prepared in Examples 1 to 4 was measured by fluorescent labeling, and the specific steps were as follows:

[0071] (1) fluorescently labeling the protective agent using a protein-fluorescent labeling kit;

[0072] (2) applying the protective agent prepared in Examples 1 to 4 to the surface of bone cultural relics at a certain site according to the method described in the examples, with the spraying thickness being 150±20 μm;

[0073] (3) After drying, use a box-type UV-visible transmission reflectometer to check the fluorescence coverage on the bone artifacts, take fluorescent photos, and use Image-Pro Plus software to quantify the fluorescence. The data is recorded as x;

[0074] (4) The same bone artifact is then sprayed with a 50±5°C, 1% ethylene glycol aqueous solution as an eluent, and then fully washed with running water for 10-30 min, and the concave part is gently brushed with a soft brush, and then the bone artifact is naturally dried, and then fixed in the same position and the operation in step (3) is repeated, and the obtained data is recorded as y;

[0075] (5) The fluorescence reduction rate was calculated according to the following formula: N = (xy) / x × 100%. The results are shown in Table 2.

[0076] (6) The bone artifacts dried in step (4) were subjected to the steps of spraying the eluent again, washing with running water, and fixing for fluorescence quantification. The obtained data were then calculated according to the formula in step (5). The results are shown in Table 3. Figure 1 A), after spraying the protective agent prepared in Example 2 ( Figure 1 B) After elution with eluent ( Figure 1 C) Photos of bone artifacts such as Figure 1 shown.

[0077] Table 2

[0078] Example Fluorescence reduction rate N Embodiment 1 97.32％ Embodiment 2 98.17％ Embodiment 3 97.94％. Embodiment 4 98.26％

[0079] Table 3

[0080] Example Fluorescence reduction rate N Embodiment 1 100％ Embodiment 2 100％ Embodiment 3 100％. Embodiment 4 100％

[0081] It can be seen from Table 2 that the fluorescence reduction rate N value range of the bone cultural relic protective agent prepared in Examples 1 to 4 of the present invention is: 96.45%≤N≤98.26%, indicating that the protective agent has good reversibility; and when the removal operation is repeated and measured again, it is found that N=100% for all experimental groups (Table 3), indicating that all protective agents are removed, and the bone cultural relics can be restored to their original bone texture state, showing excellent reversibility.

[0082] Depend on Figure 1 It can be clearly seen that after spraying the protective agent prepared in Example 2, a dense protective film is formed on the surface of the bone cultural relic, and the crisp gaps on the surface of the cultural relic are effectively filled. No obvious change is found in the surface state of the bone cultural relic after elution with the eluent compared with the surface state before reinforcement, indicating that the prepared protective agent has strong reversibility.

[0083] Experimental Test Three

[0084] The effectiveness of the protective agent prepared in Example 3 was determined as follows:

[0085] Based on the principle of non-destruction of cultural relics, a relevant simulation model was established using the modern sheep femur, and the bone deterioration was carried out by means of burning and acid immersion. Six modern sheep femur samples were randomly divided into two groups (three in each group), named model sample 1 and model sample 2. The two groups of model samples were then placed in a muffle furnace at 200°C and burned for 30 minutes to remove part of the collagen. The remaining amount of collagen in the test samples was 6-10% (the test method was: removing humus by alkali solution, then decalcifying by acid immersion, and then gelling the collagen with dilute acid at about 70°C. Finally, freeze-drying was used to obtain dry collagen powder and weigh it. The weight ratio of the dry collagen powder to the bone artifact was the collagen content. For details, see Sealy J, Johnson M, Richards M, et al. Comparison of two methods of extracting bone collag en forstable carbon and nitrogen isotope analysis: comparing whole bone demineralization with gelatinization and ultrafiltration [J]. Journal of Archaeological Science, 2014, 47: 64-69), which is similar to the collagen content of bone artifacts known in the prior art (5-12%). After that, the two groups of model samples after cauterization were placed in 0.6mol / L HCl for decalcification, and one group of samples was taken out every 48 hours according to the sample sequence, that is, model sample 1 was decalcified for 48 hours, and model sample 2 was decalcified for 96 hours. The taken out samples were rinsed with distilled water until the pH of the eluent was neutral, and naturally dried at room temperature. The obtained model samples were recorded as 1A and 2A respectively.

[0086] Draw a line on the surface of model samples 1A and 2A as a dividing mark, and cut model samples 1A and 2A into two sections with the drawn line as the boundary, one of which is evenly sprayed with the bone cultural relic protective agent prepared in Experimental Example 3 of the present invention. The section sprayed with the bone cultural relic protective agent is called the protection end, and the other section is called the non-protection end; the operation of the protection end is as follows: Ra liquid is evenly applied to the surface of a section of the protection end of model samples 1A and model sample 2A in a brushing manner, and Rb liquid is sprayed after the film is formed, and the operation is repeated 3 times; the obtained protected samples are recorded as model samples 1B and 2B. The hardness, porosity and compressive strength of model samples 1A, 1B and model samples 2A, 2B are measured by using an A-type hardness tester, a universal testing machine, and a specific surface and porosity analyzer, respectively, and the results are shown in Table 4.

[0087] Table 4

[0088] Sample name Hardness(HA) Porosity (%) Compressive strength(MPa) 1A 45±1 36.5±0.5 5.9±0.2 1B 81±2 21.3±0.2 6.1±0.4 2A 26±2 63.8±0.5 3.8±0.3 2B 47±3 43.6±0.6 4.9±0.5

[0089] The evaluation of the protective reinforcement effect of bone cultural relics mainly includes biomechanical indicators such as hardness, porosity and compressive strength. However, since bone cultural relics have certain ornamental and research properties, the porosity and compressive strength measurements in the three measurements will cause different degrees of damage to the cultural relics, resulting in irreparable damage, which is not suitable for the measurement of the cultural relics. Therefore, the present invention uses model samples for effectiveness demonstration. As can be seen from Table 4, after the bone is reinforced with the bone cultural relic protective agent prepared in Example 3 of the present invention, the hardness, porosity and compressive strength data of the model sample are significantly improved, indicating that the protective agent has a clear protective effect on deteriorated bones.

[0090] The formed protective film was subjected to energy spectrum analysis (EDS), and the results were as follows: Figure 2 As shown in the figure, after comparing with calcium carbonate and calcium phosphate, it was found that the protective film is composed of C, O, Ca, P, and N, which is consistent with the energy spectrum analysis results of calcium carbonate and calcium phosphate, indicating that the protective film is a cross-linked body of calcium carbonate and calcium phosphate. The analysis results also show the presence of N element, which is due to the gelatin component in the base film of the protective agent.

[0091] Therefore, the protective agent provided by the present invention can quickly form a protective film on the surface of the bone cultural relic, and the fastest time is 9 minutes, and the crisp gaps on the surface of the bone cultural relic can be effectively filled. The hardness, porosity and compressive strength of the bone cultural relic protected by the protective agent provided by the present invention are significantly improved; the protective agent provided can be thoroughly washed off by spraying a 50±5°C, 1% ethylene glycol aqueous solution, then rinsing with running water, and lightly brushing with a soft brush for assistance, and the bone cultural relic after washing off the protective agent has no obvious change from the surface of the cultural relic before protection / reinforcement by the protective agent, and has strong reversibility; the components of the protective agent and the eluent are all non-toxic or low-toxic preparations, and there is no safety hazard to the health of bone cultural relic protectors and visitors. The protective agent is green and environmentally friendly, and is easy to operate, and is suitable for the protection of bone cultural relics.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A reversible enzymatic protective agent for bone cultural relics, characterized in that: It comprises Ra component and Rb component, wherein Ra component is an aqueous solution of enzyme and basement membrane, and Rb component is an aqueous solution of urea, sodium β-glycerophosphate and calcium compound; The enzyme is a mixture of urease and alkaline phosphatase, the amount of urease is 30-100 IU / L Ra component, and the amount of alkaline phosphatase is 30-100 IU / L Ra component; The basement membrane is composed of gelatin and sodium alginate, the amount of gelatin is 30-70 g / L, and the amount of sodium alginate is 45-100 g / L; Use 1% ethylene glycol aqueous solution as the remover, and use flushing, soaking or soft brushing to remove the protective agent; The method for using the reversible enzymatic protective agent for bone cultural relics comprises the following steps: S1. Dissolve gelatin and sodium alginate in water, then add enzyme and stir to obtain Ra; S2, dissolving urea, sodium β-glycerophosphate and calcium compounds in water to obtain Rb; S3. Make the prepared Ra solution adhere to the part of the bone cultural relic to be protected by brushing or spraying. After standing for 10 minutes, apply Rb to the corresponding part of the bone cultural relic by spot coating or spraying, and dry naturally / freeze dry / blow dry with a fan.

2. The reversible enzymatic protective agent for bone cultural relics according to claim 1, characterized in that: The calcium compound is one of calcium chloride, calcium acetate and calcium lactate.

3. The reversible enzymatic protective agent for bone cultural relics according to claim 1, characterized in that: The dosage of the urea is 8-12 g / L, the dosage of the β-sodium glycerophosphate is 20-35 g / L, and the dosage of the calcium compound is 50-100 g / L.

4. Use of the reversible enzymatic protective agent for bone cultural relics as claimed in any one of claims 1 to 3 in the protection of bone cultural relics.

Images