A method for irradiation preparation of a nuclear pore membrane with uniform pore distribution

Abstract

The application belongs to the field of membrane material preparation, and relates to a method for preparing a nuclear pore membrane with uniform pore distribution through irradiation, comprising the following steps: determining the vertical size of a beam spot according to the size of a beam window; setting a nuclear pore membrane original film, ensuring that the nuclear pore membrane original film is stretched and taut; performing one-dimensional scanning on the nuclear pore membrane original film by using an ion beam with the determined vertical size; during the one-dimensional scanning, determining the irradiation fluence of an irradiation single scanning period according to the transmission rate v and the transverse scanning frequency f . I 0 The application couples the transmission rate v and the transverse scanning frequency f as main control parameters, achieves the accuracy of the irradiation fluence I , ensures the irradiation uniformity, avoids the transverse stripes generated by irradiation while achieving the target irradiation fluence, and realizes the uniform pore distribution in the process of preparing the nuclear pore membrane through irradiation.

Description

TECHNICAL FIELD

[0001] The application relates to a method for preparing a nuclear pore membrane with uniform hole distribution through irradiation, and belongs to the field of membrane material preparation. BACKGROUND

[0002] In the field of modern material processing, irradiation uniformity is a core element determining the consistency and reliability of material performance. It is particularly prominent in the preparation of nuclear pore membranes, and the irradiation uniformity is directly related to the key performance indicators of nuclear pore membranes, i.e. the uniformity of local hole density distribution. As a high-performance material widely used in precise separation fields such as sewage treatment, biological medicine and food preservation, quality problems such as porosity deviation and heavy hole defects of nuclear pore membranes can significantly reduce their filtration efficiency and separation precision, directly affecting the application effect of the end product.

[0003] The current mainstream beam scanning method and magnetic defocusing method still have significant technical bottlenecks in improving irradiation efficiency and uniformity. Although the beam scanning method is widely used due to its simple hardware structure and adjustable scanning parameters, when it is combined with a roll film transmission system for large-scale continuous irradiation, the mismatch between the scanning trajectory and the transmission rate can cause uneven irradiation dose distribution, forming obvious scanning stripe effects. This defect not only causes differences in hole density distribution gradient, but also causes hole structure overlap, which seriously restricts the performance stability and production qualification rate of nuclear pore membranes.

[0004] What is particularly critical is that the existing irradiation terminal technology faces double technical obstacles: first, the two-dimensional scanning system needs to precisely coordinate the bidirectional scanning parameters in the transmission direction and the vertical direction, its control system is highly dependent on the beam spot shape and faces the complex problem of matching the scanning frequency and transmission rate parameters, and the dynamic control ability is seriously insufficient; second, the magnetic defocusing technology can expand the irradiation area, but has inherent problems such as uncontrollable irradiation intensity gradient and significant edge effect, making it difficult to meet the industrialization demand of large-area uniform irradiation. These technical shortcomings lead to the current problems of low processing efficiency, high energy consumption cost and poor product consistency in the mass production of nuclear pore membranes, which have become key technical barriers restricting the development of the industry. SUMMARY

[0005] To solve the above problems, the application provides a method for preparing a nuclear pore membrane with uniform hole distribution through irradiation, which can optimize the uniformity of nuclear pore membrane irradiation preparation by adjusting the vertical size of the beam window, the horizontal scanning frequency, the transmission rate of the nuclear pore membrane and other parameters.

[0006] To achieve the above object, the present application provides the following technical scheme: a method for preparing a nuclear pore membrane with uniform hole distribution by irradiation, comprising the following steps: determining the vertical size of a beam spot according to the size of a beam window; setting a nuclear pore membrane original film, ensuring that the nuclear pore membrane original film is stretched and taut; performing one-dimensional scanning on the nuclear pore membrane original film by using an ion beam with the determined vertical size; during the one-dimensional scanning, determining the irradiation fluence of an irradiation single scanning period according to the transmission rate v and the transverse scanning frequency f . I 0 .

[0007] Further, the vertical size of the beam spot is: the beam spot is in the shape of a rectangular strip structure, the size of the length direction is greater than 5 cm, and the beam spot is uniformly distributed in the length direction.

[0008] Further, the one-dimensional scanning is a triangular wave scanning, the transverse scanning frequency f is set, and the scanning amplitude current is set and adjusted according to the width of the nuclear pore membrane original film and the characteristic parameters of the scanning device.

[0009] Further, the transmission rate v is determined by the transverse scanning frequency f , and the calculation formula of the transmission rate v is:

[0010] v / f ≈ h / n

[0011] wherein, h is the vertical size of the window, n is a scanning period coefficient, which is an integer greater than or equal to 1.

[0012] Further, under the irradiation condition that v / f ≈ h , the irradiation fluence of the irradiation single scanning period is I 0 obtained by counting the hole value of the nuclear pore membrane corresponding to the irradiation per unit area, under the irradiation condition that v / f ≈ h , the irradiation fluence of the irradiation single scanning period is I 0 The obtaining method is: counting the hole value of the nuclear pore membrane corresponding to the irradiation per unit area, and then dividing the hole value by an integer n to obtain the irradiation fluence of the irradiation single scanning period I 0 .

[0013] Further, the target irradiation fluence is adjusted by the target irradiation fluence I 目标 The transmission rate is adjusted. v The transmission rate is adjusted.

[0014] Further, the irradiation prepared nuclear pore membrane is chemically etched in 8M sodium hydroxide solution.

[0015] The technical solution of the present application has at least the following technical effects or advantages:

[0016] 1. The present application couples the transmission rate v and the transverse scanning frequency f as the main control parameters, thereby accurately controlling the irradiation fluence, ensuring irradiation uniformity, avoiding transverse stripes generated by irradiation, and realizing uniform pore distribution in the nuclear pore membrane irradiation preparation process.

[0017] 2. The present application is independent of the beam, scanning device, and irradiation object, so it can adjust the vertical size of the beam spot adjustment window, set the corresponding triangular wave scanning frequency, calculate the cumulative number and transmission speed according to the irradiation fluence, and irradiate or modify any transmission membrane material, which is suitable for mass production of nuclear pore membranes and has very high commercial value. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a schematic diagram of the triangular wave scanning irradiation preparation of the transmission nuclear pore membrane under the constraint of the beam window in an embodiment of the present application, (a) is a schematic diagram of the irradiation preparation device of the nuclear pore membrane; (b) is a schematic diagram of the one-dimensional scanning waveform of the irradiation preparation device; (c) is a schematic diagram of the beam spot shape under the constraint of the window of the irradiation preparation device; (d) is a schematic diagram of the nuclear pore membrane after irradiation;

[0019] Figure 2 is a schematic diagram of the vertical size of the beam spot in an embodiment of the present application;

[0020] Figure 3 is a comparison diagram of the nuclear pore membrane in the prior art and the nuclear pore membrane prepared in the present application, (a) is a photograph of the irradiation result of the nuclear pore membrane prepared without coupling the transmission rate in the vertical size; (b) is an enlarged view of the A, B, C three regions in (a); (c) is a statistical fluence diagram of the A, B, C three regions in (a); (d) is a photograph of the irradiation result of the nuclear pore membrane prepared in the present application; (e) is an enlarged view of the A, B, C three regions in (d); (f) is a statistical fluence diagram of the A, B, C three regions in (d). DETAILED DESCRIPTION

[0021] For those skilled in the art to better understand the technical solutions of the present application, the present application is described in detail through specific examples. However, it should be understood that the specific embodiments are provided only for better understanding of the present application, and they should not be understood as limiting the present application. In the description of the present application, it should be understood that the terms used are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0022] In order to solve the problems of the prior art, such as the high dependence of the control system on the beam spot shape, the complex matching of the scanning frequency and the transmission rate parameters, and the serious lack of dynamic regulation capacity, the present application provides a method for irradiation preparation of a nuclear pore membrane with uniform hole distribution, which aims to realize high uniformity of irradiation through accurate control and adjustment of parameters, and meet the demand of mass processing of nuclear pore membranes. The method can optimize the uniformity of the irradiation preparation of the nuclear pore membrane by adjusting the vertical size of the beam window, the lateral scanning frequency, the transmission rate of the nuclear pore membrane, and accurately controlling the irradiation dose and irradiation time and other parameters. By introducing the beam confinement window and one-dimensional scanning mode, the influence of the uncertainty of the beam spot size on the scanning can be avoided, and the probability of the occurrence of irradiation stripes during the irradiation preparation of the nuclear pore membrane is reduced, which has high practicability. The present application will be described in detail below with reference to the accompanying drawings.

[0023] The irradiation preparation structure of the nuclear pore membrane used in the present application is shown in Figure 1 The irradiation preparation structure of the nuclear pore membrane used in the present application is shown in

[0024] Example 1

[0025] The present embodiment discloses a method for irradiation preparation of a nuclear pore membrane with uniform hole distribution, comprising the following steps:

[0026] First step, determine the vertical size of the beam spot according to the size of the beam window 7;

[0027] In this embodiment, the vertical window size is selected to be 1mm hThe vertical size of the beam spot is regulated. The beam spot shape is preferably a rectangular strip structure, the length of which is greater than 5 cm, and the beam spot is evenly distributed in the length direction, such as Figure 2 shown.

[0028] The second step is to set the nuclear pore membrane. Place the original nuclear pore membrane before irradiation in the transmission device 8 to ensure that the original nuclear pore membrane is taut.

[0029] In existing irradiation terminals, large-area irradiation of nuclear pore membranes is mainly performed through two-dimensional scanning and defocusing. However, two-dimensional scanning is heavily dependent on the beam spot shape because it requires coupling the transmission speed direction and scanning perpendicular to the transmission direction. In addition, it also has problems such as complex parameters of scanning frequency and transmission speed, weak real-time adjustment capability, limited irradiation area of ​​defocusing, and poor controllability. Therefore, one-dimensional scanning is adopted in this embodiment, where the one-dimensional scanning is triangular wave scanning, and the horizontal scanning frequency is set to f , according to the width of the original nuclear pore membrane, set the scanning amplitude current, and adjust the scanning amplitude current according to the scanning device parameters to ensure the complete transverse scanning and obtain the width conditions that can completely scan the entire original nuclear pore membrane.

[0030] In this embodiment, the scanning frequency is set to f = 200 Hz. Set the scanning amplitude parameters. The width of the original nuclear pore membrane is 40 cm. To ensure complete transverse scanning, the triangle wave scanning current amplitude is set to 200 mA after adjustment.

[0031] Transmission speed v By horizontal scanning frequency f OK, transmission speed v The calculation formula is:

[0032] v / f ≈ h / n

[0033] in, h is the vertical window size, n is the scanning cycle coefficient. That is, when n=1, the transmission speed is v =600 m / min, at this time the standard irradiation area is scanned twice, that is, the standard irradiation flux of a single cycle scanning flux. n =2, the transmission speed is v =300m / min, standard irradiation area scan 4 times. n =6, v =100 m / min, the standard irradiation area is scanned 12 times. When n=3, the transmission speed is v=200 m / min, the same area is scanned and irradiated for 3 cycles. v =200 m / min, the same area is scanned and irradiated for 3 cycles.

[0034] Third step, the ion beam with the determined vertical dimension is used to scan the nuclear pore membrane in one dimension; during the one-dimensional scanning, according to the transmission rate v and the transverse scanning frequency f , the irradiation fluence of a single scanning cycle is determined. I 0 .

[0035] Under the determined irradiation conditions, i.e., the beam window height is 5 cm, the transmission rate is 300 m / min, and the scanning frequency is 200 Hz, the nuclear pore membrane is irradiated, and after etching the nuclear pore membrane, the number of pores per unit area is imaged under an optical microscope, and the irradiation fluence of a single scanning cycle I 0 is obtained by dividing the number of pores of the nuclear pore membrane by 3.

[0036] The irradiation fluence is set, and according to the transmission rate v and the transverse scanning frequency f , the irradiation fluence is adjusted, and the irradiation fluence of a single scanning cycle I 0 is counted. The target irradiation fluence I 目标 is used to adjust the transmission rate, i.e., to determine whether the irradiation fluence of a single scanning cycle I 0 reaches the target irradiation fluence I 目标 . If not, the transmission rate is adjusted. The greater the scanning frequency, the smaller the irradiation fluence of a single scanning cycle I 0 , and the lower the scanning error.

[0037] Fourth step, in a sodium hydroxide solution, the irradiated nuclear pore membrane is chemically etched at a set temperature, and the chemically etched nuclear pore membrane is cleaned.

[0038] In this embodiment, the concentration of the sodium hydroxide solution is 8M, the set temperature is 80℃, and the chemical etching time is 5 minutes. The prepared nuclear pore membrane is photographed under an optical microscope, and the irradiation fluence of a single scanning cycle of the nuclear pore membrane I 0=2.9×10 6 pores / cm 2 .

[0039] The nuclear pore membrane made by using the beam window to constrain the beam spot and the nuclear pore membrane made by not using the beam window to constrain the beam spot coupling transmission rate are compared. The comparison results are as follows: Figure 3 As shown. Figure 3 (b) and Figure 3 As shown in (e), the optical image field area of ​​the nuclear pore membrane prepared by the method of this embodiment is 260.17 μm×174.48 μm. Figure 3 In (a), the A, B, and C areas are irradiated by the conventional method. f =50 Hz, v =200 m / min, Figure 3 In (d), the A, B, and C areas are the areas where the irradiation method in this embodiment is used. f =200 Hz, v =200 m / min. Under the longitudinal constraint of the beam spot, the conditions for uniform irradiation can be calculated by coupling formulas to achieve uniform irradiation.

[0040] The present invention uses transmission speed v and horizontal scanning frequency f The main control parameters are coupled to achieve irradiation dose accuracy and ensure irradiation uniformity. The target irradiation dose can be achieved while avoiding the transverse stripes produced by irradiation, thus achieving uniform pore distribution during the irradiation preparation of nuclear pore membranes.

[0041] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the specific embodiments of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be included within the scope of protection of the claims of the present invention. The above contents are only specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A method for preparing a nuclear pore membrane with uniform pore distribution by irradiation, characterized in that: The following steps are involved: Determine the vertical size of the beam spot according to the size of the beam window; Setting a nuclear pore membrane original membrane, ensuring that the nuclear pore membrane original membrane is stretched and taut; Performing one-dimensional scanning on the original nuclear pore membrane using an ion beam having the determined vertical dimension; During the one-dimensional scanning process, according to the transmission rate v and horizontal scanning frequency f , determine the irradiation dose of a single scanning cycle I 0; The transmission rate v By horizontal scanning frequency f Determine the transmission rate v The calculation formula is: v / f ≈ h / n in, h is the vertical window size, n is the scanning period coefficient, which is an integer greater than or equal to 1; Set the irradiation dose according to the transmission speed v and horizontal scanning frequency f , adjust the irradiation dose, and calculate the irradiation dose of a single scanning cycle I 0, irradiation fluence through the target I 目标 Adjust the transmission rate, that is, determine the irradiation dose of a single scanning cycle I 0Whether the target irradiation dose is reached I 目标 If it is not reached, the transmission rate is adjusted. The greater the scanning frequency, the greater the radiation dose per single scanning cycle. I The smaller 0 is, the lower the scanning error is.

2. The irradiation preparation method of a nuclear pore membrane with uniform pore distribution according to claim 1, characterized in that: The vertical size of the beam spot is as follows: the beam spot is in a rectangular strip structure, the size of the beam spot in the length direction is greater than 5 cm, and the beam spot is evenly distributed in the length direction.

3. The irradiation preparation method of a nuclear pore membrane with uniform pore distribution according to claim 1, characterized in that: The one-dimensional scanning is triangular wave scanning, and the transverse scanning frequency f is set. The scanning amplitude current is set and adjusted according to the width of the original nuclear pore membrane and the characteristic parameters of the scanning device.

4. The irradiation preparation method of a nuclear pore membrane with uniform pore distribution according to claim 1, characterized in that: When n=1, the irradiation flux I0 of the single irradiation scanning cycle is obtained by counting the pore values ​​of the nuclear pore membrane corresponding to the irradiation per unit area. When n>1, the irradiation flux I0 of the single irradiation scanning cycle is obtained by counting the pore values ​​of the nuclear pore membrane corresponding to the irradiation per unit area, and then dividing the pore value by the integer n to obtain the irradiation flux I0 of the single irradiation scanning cycle.

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