Glass slide for microbiological quality control analysis experiment and preparation method thereof

Abstract

The invention discloses a glass slide for a microbial quality control analysis experiment and a preparation method thereof, the glass slide is of a four-layer composite structure, the four-layer composite structure sequentially comprises a glass substrate, a silicon dioxide transition layer, a silver ion composite functional layer and an outer protective layer from bottom to top, and the outer protective layer is a peelable composite film outer protective layer. All the layers achieve a synergistic effect through a specific preparation technology. The technical defects that an existing glass slide coating is weak in adhesive force and prone to pollution are overcome, the glass slide has high cleanliness, high stability and good microbial adaptability, and the chemical residue is smaller than or equal to 0.005 microgram / cm < 2 >. The requirements of high-precision microbiological quality control analysis in the fields of biomedicine, food sanitation, environmental monitoring and the like can be met, the preparation process is controllable, and batch production is easy.

Description

Technical Field

[0001] This article relates to a glass slide for microbial quality control analysis and its preparation method. Background Technology

[0002] Microbiological quality control analysis is a core experimental step in fields such as biomedicine, food hygiene, and environmental monitoring. The accuracy of its results directly determines key decisions such as product quality assessment and pollution source tracing. As the core carrier for observing microbial smears, glass slides not only need to have good light transmittance and mechanical strength, but also require extreme cleanliness and non-contamination. Surface chemical residues, microbial residues, or adsorbed impurities can all interact with microorganisms, leading to abnormal staining, observational interference, and even misinterpretation of experimental results.

[0003] Existing glass slides are mostly made of a single glass substrate or a single-layer coating structure, which has the following technical defects:

[0004] 1) The structural design is simple and lacks interface optimization, the coating is easy to peel off and cannot maintain anti-pollution performance for a long time;

[0005] 2) In the preparation process, cleaning relies on strong acids and alkalis, making it difficult to completely remove chemical residues. Furthermore, the coating has weak adhesion to the substrate and is prone to delamination.

[0006] 3) It has a single function, which can only meet basic observation needs. It lacks active anti-adsorption and antibacterial functions and is prone to adsorbing impurities or microorganisms in the experimental environment during use.

[0007] 4) Inadequate packaging and aseptic treatment can easily introduce secondary contamination during the compounding process, failing to meet the high-precision requirements of microbial quality control analysis.

[0008] To address the aforementioned issues, it is urgent to design a multi-layered composite glass slide and optimize the layered composite process. Through the synergistic function of each layer, a comprehensive performance of "high cleanliness + strong adhesion + anti-contamination + long-term stability" can be achieved. At the same time, contamination can be controlled throughout the entire preparation process to ensure the accuracy of experimental results. Summary of the Invention

[0009] The purpose of this invention is to overcome the shortcomings of existing technologies, such as weak adhesion of glass slide coatings and high risk of microbial contamination, and to provide a glass slide for microbial quality control analysis experiments and its preparation method that achieves functional synergy of each layer through a layered composite process.

[0010] A glass slide for microbial quality control analysis has a four-layer composite structure, consisting of, from bottom to top: a glass substrate, a silica transition layer, a silver ion composite functional layer, and an outer protective layer; the outer protective layer is peelably applied to the surface of the silver ion composite functional layer.

[0011] The glass substrate is quartz glass or borosilicate glass with a thickness of 0.8-1.2 mm, and the glass substrate is used for the overall load-bearing of the foundation.

[0012] The thickness of the transition layer is 20-50nm. The transition layer can effectively solve the material abrupt change problem between the glass substrate and the silver ion composite functional layer, prevent excessive light refraction, and serve as a connecting bridge between the substrate and the functional layer, effectively improving the interface bonding force.

[0013] The thickness of the silver ion composite functional layer is 50-150 nm, and the silver ion doping amount is 0.5-2.0 wt%. The silver ion composite functional layer can both support the experimental tissue to be observed and prevent bacterial contamination from the air.

[0014] The outer protective layer has a thickness of 10-30 nm, is a polyvinyl alcohol-polyethylene glycol composite system, has a porosity of ≤1.5%, and an adhesion strength of 0.08-0.25 MPa, forming a micro-adhesive bond with the silver ion composite functional layer. The outer protective layer needs to be removed before use. When not in use, the outer protective layer completely covers the surface of the silver ion composite functional layer, effectively preventing air contamination of the silver ion composite functional layer.

[0015] Furthermore, the silver particles in the silver ion composite functional layer have a diameter of 20-50 nm. In microbial quality control experiments, the resolution limit of the optical microscope used is approximately 200 nm. Therefore, using a particle size of 20-50 nm can maintain a certain antibacterial ability of the silver ions without excessively affecting the overall transparency.

[0016] A method for preparing a glass slide for microbial quality control analysis includes the following steps:

[0017] S1. Select a glass substrate without cracks or scratches, cut it to the preset size, place it in a dust-free environment, and use compressed air to blow away the surface dust for later use.

[0018] S2. Perform gradient cleaning treatment on the glass substrate;

[0019] S3. Place the cleaned glass substrate in a plasma treatment device, introduce a mixture of argon, oxygen and nitrogen, with a vacuum of 0.06-0.09 MPa, a processing power of 110-140 W, and a time of 6-7 min to activate the hydroxyl groups on the substrate surface.

[0020] S4. A transition layer sol is prepared using the sol-gel method. A mold is used to attach the transition layer sol to the surface of the glass substrate and solidify it to form a transition layer.

[0021] S5. Mix tetraethyl orthosilicate, ethanol, and deionized water in a volume ratio of 1:3.5:1. Add nitric acid to adjust the pH to 2.5-3.5. After stirring, add the nano-silver sol and continue stirring, controlling the silver ion doping amount to 0.5-2.0 wt%.

[0022] The above-mentioned functional layer sol is coated on the upper surface of the transition layer, and after curing, a thin-walled silver ion composite functional layer is formed.

[0023] S6. Place the glass slide prepared in S5 horizontally in a sterile chamber, and coat the surface of the glass slide with polyvinyl alcohol-polyethylene glycol composite colloid, ensuring that the sides and the top surface are completely covered; after completion, perform low-temperature film formation for 25-35 minutes, and control the temperature not to exceed 85℃ during the process.

[0024] S7. Finally, use sterile PE film for packaging, and perform a seal integrity test after packaging.

[0025] Furthermore, in step S2, the gradient cleaning sequentially includes neutral ultrasonic degreasing, deionized water ultrasonic cleaning, and ultrapure water ultrasonic rinsing. Neutral ultrasonic degreasing removes surface release agents, fingerprint grease, and other organic contaminants without corroding the glass substrate, preventing oil stains from affecting subsequent coating adhesion. Deionized water ultrasonic cleaning washes away residual neutral degreasing agent, preventing its components from interfering with the performance of subsequent functional layers. Ultrapure water ultrasonic rinsing further removes trace inorganic impurities and ions, ensuring substrate surface cleanliness and providing a clean base for plasma activation and coating preparation.

[0026] Furthermore, the outer protective layer is a peelable composite film, and its preparation process includes the following steps:

[0027] S61. Weigh out tetraethyl orthosilicate, polyvinyl alcohol, and polyethylene glycol in a mass ratio of 3:5:2. This ratio allows the inorganic phase (tetraethyl orthosilicate) to be compatible with the organic phase (polyvinyl alcohol and polyethylene glycol), taking into account both the wear resistance and peelability of the protective layer.

[0028] S62. First, dissolve polyvinyl alcohol in deionized water at 80-85℃ to form a transparent solution. After cooling to 25-30℃, add tetraethyl orthosilicate and isopropanol, then add polyethylene glycol and stir for 10 minutes. Low-temperature stirring can prevent tetraethyl orthosilicate from hydrolyzing excessively in advance and ensure that each component is evenly dispersed.

[0029] S63. Finally, add 25-28wt% ammonia water to adjust the pH to 7.5-8.5, and stir at 150-200rpm for 20-30 minutes at 25-30℃ to form a composite colloid. The composite colloid has uniform stability, which lays the foundation for subsequent low-temperature film formation.

[0030] Furthermore, the curing conditions for the transition layer are: holding at 120-150℃ for 1.5-2.5 hours. This temperature and time allow the transition layer sol to fully cross-link and cure, forming a dense silica film. This ensures the interfacial bonding between the transition layer and the glass substrate and the silver ion composite functional layer, preventing delamination during subsequent use, while also reducing internal porosity and ensuring light transmittance.

[0031] Furthermore, the functional layer sol is applied by spin coating at a speed of 3000-5000 rpm. Centrifugal force is used to control the uniformity of the coating thickness, avoiding localized areas that are too thick or too thin, which would affect light transmission and anti-adsorption effects. The coating time is 30-60 seconds. The curing conditions are: holding at 180-220℃ for 2-3 hours. High-temperature holding allows the functional layer sol to fully cure, ensuring uniform dispersion of silver ions, while improving the density of the functional layer, enhancing its antimicrobial adsorption capacity, and without destroying the antibacterial activity of silver ions.

[0032] Furthermore, in step S6, a layer of polyvinylpyrrolidone aqueous solution is pre-coated onto the surface of the glass slide to be coated. After coating, a low-temperature film-forming process is performed on the surface of the polyvinylpyrrolidone aqueous solution to prepare an outer protective layer. This aqueous solution can form an ultra-thin isolation layer on the surface of the silver ion composite functional layer, reducing the adhesion between the outer protective layer and the functional layer, ensuring that the outer protective layer can be easily peeled off during use without damaging the functional layer; the low-temperature film-forming process after coating prepares the outer protective layer, and the polyvinylpyrrolidone is easy to remove, requiring only simple treatment before subsequent use, leaving no residual interference.

[0033] Beneficial effects:

[0034] The four-layer composite structure of the slide works in conjunction with the fabrication process. The transition layer connects the substrate and the functional layer. Combined with plasma activation and the sol-gel method, the bonding force between the layers is enhanced to prevent delamination.

[0035] The silver ion composite functional layer inhibits microbial adsorption, while the low-porosity outer protective layer provides physical contamination protection, offering dual protection for cleanliness. Simultaneously, the outer protective layer has suitable adhesion, allowing for easy manual peeling without damaging the functional layer. It can be mass-produced to meet the needs of microbial quality control for stability, cleanliness, and ease of use. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the overall structure of a glass slide used in microbial quality control analysis experiments;

[0037] Figure 2 This is a partial cross-sectional view of this type of glass slide;

[0038] Figure 3 This is a schematic diagram of the removal of the outer protective layer from this type of glass slide;

[0039] In the diagram: 1. Glass substrate layer, 2. Transition layer, 3. Silver ion composite functional layer, 4. Outer protective layer. Detailed Implementation

[0040] To enhance understanding of the present invention, the present invention will be further described in detail below with reference to embodiments and accompanying drawings. These embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0041] Example 1: As Figure 1-3 As shown, a glass slide for microbial quality control analysis includes a glass substrate layer 1, a transition layer 2, a silver ion composite functional layer 3, and an outer protective layer 4. The preparation process includes the following steps:

[0042] S1. Select high borosilicate glass without cracks or scratches as the substrate, cut it to a standard size of 25mm×75mm, and place it in a dust-free environment to blow away surface dust with compressed air.

[0043] S2. Gradient cleaning: First, perform neutral ultrasonic degreasing for 15 minutes, then ultrasonic cleaning with deionized water for 10 minutes, and finally ultrasonic rinsing with ultrapure water for 5 minutes. Dry and set aside.

[0044] S3. Plasma activation: The cleaned substrate is placed in a plasma treatment device, and a mixture of argon, oxygen and nitrogen (volume ratio 2:1:1) is introduced. The vacuum degree is controlled at 0.07MPa, the processing power is 120W and the time is 6.5min to activate the surface hydroxyl groups.

[0045] S4. Preparation of transition layer: The silica transition layer sol was prepared by sol-gel method. The sol was uniformly attached to the surface of the substrate through a mold and placed in an oven at 130℃ for 2 hours to solidify and form a transition layer with a thickness of 35nm.

[0046] S5. Preparation of functional layer: Tetraethyl orthosilicate, ethanol, and deionized water were mixed at a volume ratio of 1:3.5:1. Nitric acid was added to adjust the pH to 3.0. After stirring for 30 min, nano-silver sol was added and stirring was continued for 20 min, controlling the silver ion doping amount to 1.2 wt%. The sol was spin-coated at 4000 rpm for 30 s to coat the surface of the transition layer. The layer was then placed in an oven and kept at 200℃ for 2.5 h to cure and form a silver ion composite functional layer with a thickness of 100 nm. The silver particle size was measured to be 35 nm.

[0047] S6. Preparation of the outer protective layer: Weigh tetraethyl orthosilicate, polyvinyl alcohol, and polyethylene glycol in a mass ratio of 3:5:2. Dissolve polyvinyl alcohol in deionized water at 82℃ to form a transparent solution. After cooling to 28℃, add tetraethyl orthosilicate and isopropanol, then add polyethylene glycol and stir for 10 min. Finally, add 26wt% ammonia to adjust the pH to 8.0. Stir at 180 rpm for 25 min at 28℃ to form a composite colloid. Coat the surface of the functional layer with a layer of polyvinylpyrrolidone aqueous solution. Place a glass slide horizontally in a sterile chamber and uniformly coat it with the composite colloid. Deposit at 80℃ for 30 min to form an outer protective layer with a thickness of 20 nm.

[0048] S7. Packaging Inspection: Aseptic PE film is used for sealed packaging. The seal integrity is tested by pressure decay method. If it passes the test, it is considered a finished product.

[0049] Testing revealed that the chemical residue of the slides prepared in this embodiment was 0.003 μg / cm², the outer protective layer could be easily peeled off, the coating adhesion met the standards, and no abnormal staining or contamination was observed in the microbial quality control analysis experiment, significantly improving the accuracy of the experimental results.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A glass slide for microbial quality control analysis, characterized in that, It has a four-layer composite structure, from bottom to top: glass substrate, silicon dioxide transition layer, silver ion composite functional layer and outer protective layer; the outer protective layer is peelably covered on the surface of the silver ion composite functional layer. The glass substrate is quartz glass or borosilicate glass with a thickness of 0.8-1.2 mm; The thickness of the transition layer is 20-50 nm; The thickness of the silver ion composite functional layer is 50-150 nm, and the silver ion doping amount is 0.5-2.0 wt%. The outer protective layer is a polyvinyl alcohol-polyethylene glycol composite system with a thickness of 10-30 nm, a porosity of ≤1.5%, and an adhesion of 0.08-0.25 MPa, forming a micro-adhesive connection with the silver ion composite functional layer.

2. The microbial quality control analysis slide according to claim 1, characterized in that, The silver particles in the silver ion composite functional layer have a diameter of 20-50 nm.

3. A method for preparing a glass slide for microbial quality control analysis as described in claim 1, characterized in that, Includes the following steps: S1. Select a glass substrate without cracks or scratches, cut it to the preset size, place it in a dust-free environment, and use compressed air to blow away the surface dust for later use. S2. Perform gradient cleaning treatment on the glass substrate; S3. Place the cleaned glass substrate in a plasma treatment device, introduce a mixture of argon, oxygen and nitrogen, with a vacuum of 0.06-0.09 MPa, a processing power of 110-140 W, and a time of 6-7 min to activate the hydroxyl groups on the substrate surface. S4. A transition layer sol is prepared using the sol-gel method. A mold is used to attach the transition layer sol to the surface of the glass substrate and solidify it to form a transition layer. S5. Mix tetraethyl orthosilicate, ethanol, and deionized water in a volume ratio of 1:3.5:

1. Add nitric acid to adjust the pH to 2.5-3.

5. After stirring, add the nano-silver sol and continue stirring, controlling the silver ion doping amount to 0.5-2.0 wt%. The above-mentioned functional layer sol is coated on the upper surface of the transition layer, and after curing, a thin-walled silver ion composite functional layer is formed. S6. Place the glass slide prepared in S5 horizontally in a sterile chamber, and coat the surface of the glass slide with polyvinyl alcohol-polyethylene glycol composite colloid, ensuring that the sides and the top surface are completely covered; after completion, perform low-temperature film formation for 25-35 minutes, and control the temperature not to exceed 85℃ during the process. S7. Finally, use sterile PE film for packaging, and perform a seal integrity test after packaging.

4. The method for preparing a glass slide for microbial quality control analysis according to claim 3, characterized in that, In step S2, the gradient cleaning process includes, in sequence, neutral ultrasonic degreasing, deionized water ultrasonic cleaning, and ultrapure water ultrasonic rinsing.

5. The method for preparing a glass slide for microbial quality control analysis according to claim 3, characterized in that, The outer protective layer is a peelable composite film, and its preparation process includes the following steps: S61. Weigh out tetraethyl orthosilicate, polyvinyl alcohol, and polyethylene glycol in a mass ratio of 3:5:

2. S62. First, dissolve polyvinyl alcohol in deionized water at 80-85℃ to form a transparent solution. After cooling to 25-30℃, add tetraethyl orthosilicate and isopropanol, and then add polyethylene glycol and stir for 10 minutes. S63. Finally, add 25-28wt% ammonia water to adjust the pH to 7.5-8.5, and stir at 150-200rpm for 20-30 minutes at 25-30℃ to form a composite colloid.

6. The method for preparing a glass slide for microbial quality control analysis according to claim 3, characterized in that, The curing conditions for the transition layer are: heat preservation at 120-150℃ for 1.5-2.5 hours.

7. The method for preparing a glass slide for microbial quality control analysis according to claim 3, characterized in that, The functional layer sol is applied by spin coating at a speed of 3000-5000 rpm for 30-60 seconds. The curing conditions are: heat preservation at 180-220℃ for 2-3 hours.

8. The method for preparing a glass slide for microbial quality control analysis according to claim 3, characterized in that, In step S6, a layer of polyvinylpyrrolidone aqueous solution is pre-coated on the surface of the glass slide to be coated. After coating, a low-temperature film is formed on the surface of the polyvinylpyrrolidone aqueous solution to prepare an outer protective layer.

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