Method for testing aluminum contamination amount in sample after plasma sterilization and application

Abstract

The invention provides a method for testing the aluminum contamination amount in plasma sterilization or a sample and application of the method, the aluminum contamination amount Q of the sterilized sample in unit area is calculated through a mathematical relational expression (I): Q = 5.43 P-0. 15, and a sterilization packaging material adopted in the formula (I) is a polymer modified aluminum adsorption material. The polymer is selected from at least one of polymers containing sulfonic acid groups. According to the numerical relationship between the aluminum contamination amount and the aluminum content of the sterilization packaging material, the aluminum contamination amount of the sterilization instrument can be calculated by measuring the aluminum content of the sterilization packaging material, and the method has important reference significance for reducing or preventing the sterilization instrument from being contaminated by aluminum by designing and transforming the sterilization packaging material.

Description

Technical Field

[0001] The present invention relates to the technical field of plasma sterilization. Further, it is a method for testing the amount of aluminum contamination in a sample after plasma sterilization and its application. Background Art

[0002] The plasma sterilization technology was born in the United States in the 1980s and entered China in 2004. Currently, it has been widely used in medical devices such as endoscopes, ophthalmic lenses, fiber optic cables, and intracranial pressure sensors. This technology has four major characteristics: First, sterilization is carried out at room temperature, which is especially suitable for medical devices that are afraid of moisture and heat. Second, it is very environmentally friendly and there is no harmful residue like ethylene oxide sterilization. Third, it is mild and will not cause damage to the material of the device. Fourth, it is convenient and can complete sterilization in 50 minutes and can be used directly after taking it out.

[0003] Research has found that plasma can cause aluminum impurity contamination, and the contamination source is the inner wall of the sterilization chamber, because aluminum alloy is the most commonly used material for the inner wall of the sterilization chamber. Although the medical device is completely sealed in the sterilization packaging during the sterilization process, free aluminum can penetrate through the sterilization packaging and enter the medical device to form aluminum contamination. These contaminated aluminums can enter the human body during the use of the medical device, causing bone damage and brain damage.

[0004] In the prior art, methods for measuring the content of metal impurities in solid materials include techniques such as inductively coupled plasma mass spectrometry (ICP-MS), secondary ion mass spectrometry (SIMS), X-ray photoelectron spectroscopy (XPS), and Auger emission spectroscopy (AES). However, these techniques require the test sample to be very small (in the order of cm*cm*mm), and the sample will be damaged during the test process. Therefore, they are not suitable for measuring the impurity contamination of expensive medical devices such as endoscopes that need to be used repeatedly. Therefore, it is necessary to develop a method suitable for measuring the amount of aluminum contamination caused by plasma sterilization. Summary of the Invention

[0005] To solve the problems in the prior art, the present invention proposes a method for testing the amount of aluminum contamination in a sample after plasma sterilization and its application in measuring the amount of aluminum contamination. The sterilization packaging material used in the present invention is a polymer-modified aluminum adsorption material, and the polymer is a polymer containing sulfonic acid groups, which can effectively adsorb the aluminum generated during the plasma sterilization process, so as to measure the amount of aluminum contamination generated by plasma sterilization.

[0006] One of the purposes of the present invention is to provide a method for testing the amount of aluminum contamination in a sample after plasma sterilization, including: packaging the sample with a sterilization packaging material and placing it in a plasma sterilization chamber for sterilization treatment. After the sterilization treatment, test the aluminum content P per unit volume in the sterilization packaging material after the sterilization treatment (unit: mg / cm 3), the aluminum contamination amount Q per unit area in the sterilized sample is obtained by calculation (unit: mg / cm 2 ), where the numerical values of P and Q satisfy the mathematical relationship (I):

[0007] Q = 5.43P -0.15 Equation (I)

[0008] The sterilization packaging material is a polymer-modified aluminum adsorption material, and the polymer is selected from at least one of polymers containing sulfonic acid groups.

[0009] According to the present invention, in the test method for the aluminum contamination amount in the sample after plasma sterilization:

[0010] The sterilization packaging material includes an aluminum adsorption material support layer and a polymer-modified layer tightly arranged on at least one side of the support layer;

[0011] The polymer is selected from at least one of perfluorosulfonic acid resin and sulfonated polymer, preferably at least one of sulfonated polyether ketone and sulfonated polyethersulfone;

[0012] The ion exchange capacity of the polymer is 0.4 - 2.5 mmol / g, preferably 0.5 - 2.0 mmol / g, and more preferably 0.9 - 2.0 mmol / g.

[0013] According to the present invention, the sterilization treatment conditions in the test method for the aluminum contamination amount in the sample after plasma sterilization are not particularly limited, and the commonly used sterilization treatment conditions in the art can be adopted. For example, the sterilization treatment conditions that can be adopted are: the temperature is 25 - 60°C, the pressure is 0.01 - 200 Pa, and the time is 1 - 60 min.

[0014] According to the present invention, in the sterilization packaging material:

[0015] The support layer is selected from at least one of polypropylene, polyethylene, and polyester, preferably a non-woven fabric of polypropylene and / or polyester material;

[0016] The thickness of the support layer is 0.1 - 1 mm, preferably 0.2 - 0.5 mm;

[0017] The thickness of the polymer-modified layer is 0.1 - 100 μm, preferably 0.5 - 50 μm.

[0018] According to the present invention, the sterilization packaging material is obtained by the following preparation method: mixing the polymer with a solvent to obtain a dispersion liquid, and then coating it on at least one surface of the support layer, and drying to obtain the sterilization packaging material.

[0019] According to the present invention, in the preparation method of the sterilization packaging material:

[0020] The solvent is selected from a mixed solution of alcohol and water. Preferably, the alcohol is selected from at least one of methanol, ethanol, and n-butanol, and the volume ratio of alcohol to water in the solvent is (1-10):1;

[0021] The concentration of the polymer in the dispersion is 1-20 wt%;

[0022] The coating method is dip coating; preferably, the dip coating time is 10-300 s, more preferably 30-120 s, and further preferably 60-120 s;

[0023] The drying temperature is 40-80 °C.

[0024] According to the present invention, the method for establishing the mathematical relationship (I) includes:

[0025] A) Testing the aluminum concentration at different depths in the sample to obtain the distribution curve C0(x), where x is the depth;

[0026] B) Packaging the sample with the first sterilization packaging material and placing it in a plasma sterilization chamber for sterilization;

[0027] C) Taking out the sample after sterilization, testing the aluminum content P1 per unit volume of the first sterilization packaging material, and the aluminum concentration at different depths in the sample after sterilization treatment to obtain the distribution curve C1(x), where x is the depth;

[0028] D) Packaging the sample with different sterilization packaging materials, repeating steps B) and C), to obtain the aluminum content P per unit volume of different sterilization packaging materials after sterilization treatment n , and the aluminum concentration at different depths in the sample after sterilization treatment to obtain the distribution curve C n (x), where x is the depth;

[0029] Calculating the aluminum contamination amount Q per unit area of the sample after sterilization treatment through formula (1) n ;

[0030]

[0031] In formula (1), C represents the aluminum concentration at different depths in the sample (the number of aluminum atoms per unit volume), a is the depth value corresponding to when the aluminum concentration in the sample after sterilization treatment reaches the detection limit, b is the depth value corresponding to when the aluminum concentration in the sample without sterilization treatment reaches the detection limit, that is, the detection limit reached by the detection instrument, M Al represents the molar mass of aluminum, N A represents Avogadro's constant, and n is the number of different sterilization packaging materials used; among them, the number of different sterilization packaging materials used is not particularly limited, at least 2, and n in formula (1) is an integer from 1 to 10;

[0032] E) Establish a plane XY orthogonal coordinate system, input P1…P n numerical values on the X-axis, and input Q1…Q n numerical values on the Y-axis. Obtain the mathematical relationship (I) between the Q numerical value and the P numerical value by fitting:

[0033] Q = 5.43P -0.15 Equation (I).

[0034] According to the present invention, in the method for establishing the mathematical relationship (I):

[0035] The sample is selected from at least one of silicon, germanium, gallium nitride, silicon carbide, and gallium arsenide, preferably silicon;

[0036] In the steps A), C), and D), the test method for the aluminum concentration distribution in the sample adopts SIMS, AES, or XPS, preferably SIMS;

[0037] Fitting can be assisted by software with a fitting function, preferably origin, matlab, or excel.

[0038] According to the present invention, in the steps C) and D) of the method for establishing the mathematical relationship (I), the test method for the aluminum content P per unit volume of the sterilized packaging material after sterilization treatment includes: n :

[0039] i) Prepare aluminum standard solutions with different concentrations, use ICP-MS to test the response intensity of aluminum ions in the aluminum standard solutions with different concentrations, establish a standard curve, and the obtained standard curve is y = 522.477x + 653.020;

[0040] ii) Digest the sterilized packaging material adsorbed with aluminum after sterilization treatment to completely dissolve the adsorbed aluminum in the digestion solution and make the volume constant to V n ;

[0041] iii) Then dilute the digestion solution with a constant volume, and record the dilution multiple as N to obtain a diluted test solution;

[0042] iv) Use ICP-MS to test the response intensity of aluminum ions in the diluted test solution, and obtain the mass concentration S of aluminum ions in the diluted test solution by the external standard method and substituting into the standard curve in step i) n ;

[0043] v) Calculate the aluminum content R adsorbed on the sterilized packaging material after sterilization treatment through formula (2) n ;

[0044]

[0045] In formula (2), R n is the aluminum content adsorbed on the sterilized packaging material after sterilization, with the unit of mg / g; S n is the mass concentration of aluminum ions in the diluted test solution, with the unit of mg / mL; V n is the volume of the digested solution after volume fixation, with the unit of mL; N is the dilution factor; M n is the mass of the sterilized packaging material, with the unit of g;

[0046] ⅵ) Calculate the aluminum concentration P per unit volume of the sterilized packaging material after sterilization through formula (3) n :

[0047] P n = R n × ρ n Formula (3)

[0048] In formula (3), P n is the aluminum concentration per unit volume of the sterilized packaging material after sterilization, with the unit of mg / cm 3 ; R n is the aluminum content adsorbed on the sterilized packaging material after sterilization, with the unit of mg / g; ρ is the density of the sterilized packaging material, with the unit of g / cm 3 .

[0049] According to the present invention, in the test method for the aluminum content P n in the sterilized packaging material after sterilization:

[0050] In the step ⅰ), the solvent in the aluminum standard solution is selected from pure water or a pure aqueous nitric acid solution with a concentration not exceeding 5%, and the nitric acid used is of a purity above analytical grade; the standard product in the aluminum standard solution can be a commercially available aluminum standard solution;

[0051] In the step ⅱ), the digested solution is a nitric acid solution. Preferably, the digested solution used is a nitric acid solution with a mass concentration of 50-70%;

[0052] In the step ⅱ), the volume V n of the digested solution after volume fixation has no particular limitation. For example, V n is 10-500 mL;

[0053] In the step ⅲ), the dilution factor N has no particular limitation. For example, N is 10-1000.

[0054] The second object of the present invention is to provide the application of the above test method for the aluminum contamination amount in the sample after plasma sterilization in the test of the aluminum contamination amount caused by plasma sterilization.

[0055] The polymer-modified aluminum adsorption material used in the present invention can effectively adsorb the aluminum generated during the plasma sterilization process by modifying the support layer (such as non-woven fabric). Its adsorption mechanism is mainly ion exchange, which results from the combination of hydrogen ions ionized from sulfonic acid groups with aluminum ions to form a stable chemical substance. By testing the aluminum content in the polymer-modified aluminum adsorption material, the aluminum contamination amount of the sterilization treatment object (such as sterilization instruments) can be calculated through the mathematical relationship between the aluminum contamination amount Q of the sterilization treatment object and the aluminum concentration P of the sterilization packaging material, which has important reference significance for reducing or preventing the aluminum contamination of sterilization instruments by designing and modifying the sterilization packaging material.

[0056] In the ranges and any values disclosed in the present invention, the endpoints and any values are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein. In the following text, in principle, the various technical solutions can be combined with each other to obtain new technical solutions, which should also be regarded as specifically disclosed herein.

[0057] Compared with the prior art, the present invention has the following advantages:

[0058] The sterilization packaging material of the present invention can effectively adsorb the aluminum generated during the plasma sterilization process, so that the aluminum contamination amount of the sterilization instrument can be calculated, which can be used to guide the design and modification of the sterilization packaging material and reduce the aluminum contamination of the sterilization instrument. Description of the Drawings

[0059] Figure 1 It is a numerical relationship curve of the aluminum contamination amount of the sterilized article and the aluminum concentration of the sterilization packaging material obtained by fitting the test results of Examples 1 to 4, and the actual aluminum contamination amount of the sterilized article; wherein, the abscissa is the numerical value P of the aluminum content per unit volume in the sterilization packaging material after sterilization treatment, and the ordinate is the numerical value Q of the aluminum contamination amount per unit area in the sample after sterilization treatment.

[0060] Figure 2 It is the concentration distribution curve of aluminum in the silicon wafer samples before and after sterilization treatment in Examples 1 to 4. Among them, C0 is the concentration distribution curve of aluminum in the silicon wafer sample without sterilization treatment, and C1 to C4 are the concentration distribution curves of aluminum in the silicon wafer samples after sterilization treatment in Examples 1 to 4 respectively; the abscissa is the sample test depth, in units of nm, and the ordinate is the number of aluminum atoms per unit volume at the corresponding depth in the sample, in units of / cm 3 。 Detailed Embodiments

[0061] The present invention will be specifically described below in conjunction with specific drawings and embodiments. It is necessary to point out here that the following embodiments are only for further illustration of the present invention and cannot be construed as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention still fall within the protection scope of the present invention.

[0062] In addition, it should be noted that the various specific technical features described in the following specific embodiments can be combined in any appropriate manner without conflict. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0063] Furthermore, any combination can be made among the various different embodiments of the present invention as long as it does not violate the idea of the present invention. The technical solutions thus formed belong to a part of the original public content of this specification and also fall within the protection scope of the present invention.

[0064] If there is no special limitation on the raw materials used in the examples and comparative examples, they are all disclosed in the prior art. For example, they can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0065] In the embodiments of the present invention, the term "soaking" used herein means complete immersion.

[0066] Example 1

[0067] Preparation of the sterilization packaging material:

[0068] Select a commercially available non-woven fabric W1 for sterilization made of polypropylene, with a size of 20 cm * 20 cm. Immerse the non-woven fabric in a Nafion D521 dispersion (the dispersion uses a mixed solvent with a volume ratio of water to isopropanol of 1:3) for 60 s (the concentration of the perfluorosulfonic acid-based polymer resin is 5 wt%), and dry it at 60 °C to obtain a polymer-modified aluminum adsorption sterilization packaging material E1. Among them, the thickness of the polymer-modified layer on one side of the sterilization packaging material E1 is 3 μm.

[0069] Test for the amount of aluminum contamination in the sample after plasma sterilization:

[0070] Using a commercially available standard solution of 100 ppm aluminum as the stock solution, the stock solution was serially diluted to 500 ppb, 100 ppb, 20 ppb, and 4 ppb with pure water or a nitric acid solution of purity above superior grade with a concentration not exceeding 5% prepared with pure water to obtain different standard solutions. Then, each of the diluted standard solutions was injected into an ICP-MS instrument to measure the mass spectrometry intensity of the corresponding aluminum signal. Finally, for the four groups of data, with the concentration of the standard solution as the x value, i.e., 500 ppb, 100 ppb, 20 ppb, and 4 ppb, and the y value being the mass spectrometry intensity of the aluminum signal corresponding to the respective x value, a standard curve was obtained by fitting: y = 522.477x + 653.020.

[0071] From the mass and volume of the obtained sterilized packaging material E1, the density of the sterilized packaging material E1 prepared in Example 1 was calculated to be 0.21 g / cm 3 . The sterilized packaging material E1 was cut into pieces each with a length and width of 20 cm. A 1 cm 2 *1 cm 2 silicon wafer F1 was taken, washed, and well-packaged with E1, then placed in a sterilization chamber, and a short-cycle sterilization program was started (plasma treatment time was 660 s, temperature was 53 °C, pressure was 150 Pa). After sterilization, it was taken out. A part was cut from E1, weighed, and the recorded mass M1 was 0.10 g. Then, the aluminum element adsorbed on this part of E1 was completely dissolved in a digestion solution (nitric acid solution, 65 wt%) by wet digestion and made up to a volume V1 = 100 mL. The digestion solution was diluted N = 100 times to prepare a sample solution. The response intensity of aluminum ions in the sample solution was measured using ICP-MS, and substituting it into the above standard curve equation, the mass concentration S1 of aluminum ions in the diluted test solution was obtained as 0.24E-5 mg / mL.

[0072] Through formula (2), the aluminum content R1 adsorbed on the sterilized packaging material E1 after sterilization treatment was calculated to be 0.24 mg / g.

[0073]

[0074] The aluminum concentration P1 adsorbed on the above sterilized packaging material E1 was calculated by formula (3) to be 0.05 mg / cm 3 .

[0075] P n = R n × ρ n Formula (3)

[0076] The concentration distribution curve C0 of aluminum in F1 and the concentration distribution curve C1 of aluminum in the silicon wafer sample F1 after sterilization treatment were measured using SIMS. Using formula (1), the actual value Q1 of the aluminum contamination amount in the silicon wafer sample F1 was obtained as 8.3 mg / cm 2 .

[0077]

[0078] Example 2

[0079] Preparation of the sterilization packaging material:

[0080] Select two commercially available non-woven fabrics W1 made of polypropylene for sterilization, cut them out, with a size of 20 cm * 20 cm. Dissolve sulfonated polyether ketone in a mixed solution of isopropanol and water (the volume ratio of isopropanol to water is 5:1) to prepare a 5 wt% sulfonated polyether ketone dispersion; immerse the non-woven fabric in the sulfonated polyether ketone dispersion for 120 s and dry it at 80 °C to obtain the polymer-modified aluminum adsorption sterilization packaging material E2. Among them, the thickness of the polymer-modified layer on one side of the sterilization packaging material E2 is 12 μm.

[0081] Measurement of the aluminum contamination amount in the sample after plasma sterilization:

[0082] The sterilization packaging material E2 prepared in Example 2 has a density of 0.19 g / cm 3 . Cut the sterilization packaging material E2 into pieces each with a length and width of 20 cm. Cut out a silicon wafer F2 of 1 cm 2 *1 cm 2 . Wash it and pack it well with E2, put it into the sterilization chamber, and start the short-cycle sterilization program (the plasma treatment time is 660 s, the temperature is 53 °C, and the pressure is 150 Pa). After sterilization, take it out. Cut a part from E2, weigh it and record its mass M2 as 0.1 g, then completely dissolve the aluminum element adsorbed on this part of E2 in the digestion solution (nitric acid solution, 65 wt%) by wet digestion and make the volume constant to V1 = 100 mL. Dilute the digestion solution by N = 100 times to obtain the sample solution. Measure the aluminum ion response intensity in the sample solution by ICP-MS. According to the standard curve equation obtained in Example 1, the mass concentration S2 of aluminum ions in the diluted test solution is 2.42E-5 mg / ml. Calculate the aluminum content R2 adsorbed on the sterilization packaging material E2 after sterilization treatment through formula (2) = 2.42 mg / g. Calculate the aluminum concentration P2 adsorbed on the above sterilization packaging material through formula (3) = 0.46 mg / cm 3 . Use SIMS to measure the concentration distribution C2 of aluminum in the silicon wafer sample F2, and use formula (1) to obtain the actual value Q2 of the aluminum contamination amount in F2 as 6.0 mg / cm 2 .

[0083] Example 3

[0084] Preparation of the sterilization packaging material:

[0085] Select a commercially available non-woven fabric W1 for sterilization made of polypropylene, with a size of 20 cm * 20 cm. Dissolve sulfonated polyether ketone in a mixed solution of isopropanol and water (the volume ratio of isopropanol to water is 3:1) to prepare a 15 wt% sulfonated polyether ketone dispersion; immerse the non-woven fabric in the sulfonated polyether ketone dispersion for 60 s and dry it at 60 °C to obtain a polymer-modified aluminum adsorption sterilization packaging material E3. Among them, the thickness of the polymer-modified layer on one side of the sterilization packaging material E3 is 18 μm.

[0086] Determination of aluminum contamination in the sterilized sample:

[0087] The sterilization packaging material E3 prepared in Example 3 has a density of 0.20 g / cm 3 . Cut the sterilization packaging material E3 into pieces each with a length and width of 20 cm. Cut out a 1 cm 2 *1 cm 2 silicon wafer F3, wash it and pack it well with E3, put it into the sterilization chamber, and start the short-cycle sterilization program (plasma treatment time is 660 s, temperature is 53 °C, pressure is 150 Pa). After sterilization, take it out. Cut a part from E3, weigh it and record its mass M3 as 0.1 g, then completely dissolve the aluminum element adsorbed on this part of E3 in the digestion solution (nitric acid solution, 65 wt%) by wet digestion and make the volume constant to V1 = 100 mL. Dilute the digestion solution by N = 100 times to obtain a sample solution. Measure the response intensity of aluminum ions in the sample solution by ICP-MS. According to the standard curve equation obtained in Example 1, the mass concentration S3 of aluminum ions in the diluted test solution is 6.90E-5 mg / ml. Calculate the aluminum content R3 adsorbed on the sterilization packaging material E3 after sterilization treatment through formula (2) as 6.90 mg / g. Calculate the aluminum concentration P3 adsorbed on the above sterilization packaging material E3 through formula (3) as 1.38 mg / cm 3 . Use SIMS to measure the aluminum concentration distribution C3 in the silicon wafer sample F3 after sterilization treatment, and use formula (1) to obtain the actual value of the aluminum contamination in F3 as 5.3 mg / cm 2 .

[0088] Example 4

[0089] Preparation of sterilization packaging material:

[0090] Select a commercially available non-woven fabric W2 for sterilization made of PET, with a size of 20 cm * 20 cm. Immerse the non-woven fabric in Nafion D520 dispersion for 60 s (the concentration of perfluorosulfonic acid-based polymer resin is 20 wt%), and dry it at 60 °C to obtain a polymer-modified aluminum adsorption sterilization packaging material E4. Among them, the thickness of the polymer-modified layer on one side of the sterilization packaging material E4 is 20 μm.

[0091] Determination of aluminum contamination in the sterilized sample:

[0092] The sterilized packaging material E4 prepared in Example 4 has a density of 0.21 g / cm 3 . The sterilized packaging material E4 was cut into pieces each with a length and width of 20 cm. A 1 cm 2 *1 cm 2 silicon wafer F4 was taken, washed and then well-packaged with E4, placed in a sterilization chamber, and the short-cycle sterilization program was started (plasma treatment time: 660 s, temperature: 53 °C, pressure: 150 Pa). After sterilization, it was taken out. A part was cut from E4, weighed and the recorded mass M4 was 0.1 g. Then, the aluminum element adsorbed on this part of E4 was completely dissolved in the digestion solution (nitric acid solution, 65 wt%) by wet digestion and made up to a volume V1 = 100 mL. The digestion solution was diluted N = 100 times to prepare a sample solution. The response intensity of aluminum ions in the sample solution was measured by ICP-MS. According to the standard curve equation obtained in Example 1, the mass concentration S4 of aluminum ions in the diluted test solution was 8.67E-5 mg / ml. The aluminum content R4 adsorbed on the sterilized packaging material E4 after sterilization treatment was calculated by formula (2) as 8.67 mg / g. The aluminum concentration P4 adsorbed on the above sterilized packaging material E4 was calculated by formula (3) as 1.82 mg / cm 3 . The concentration distribution C4 of aluminum in the silicon wafer sample F4 after sterilization treatment was measured by SIMS, and the actual value of the aluminum contamination amount in F4 was obtained by formula (1) as 5.1 mg / cm 2 .

[0093] Establishment of the mathematical relationship (Ⅰ):

[0094] A plane XY orthogonal coordinate system was established. The values of P1, P2, P3, and P4 were input on the X-axis, and the values of Q1, Q2, Q3, and Q4 were input on the Y-axis. The mathematical relationship (Ⅰ) between Q and P was obtained by fitting with Origin:

[0095] Q = 5.43P -0.15 Equation (Ⅰ)

[0096] Calculated by the mathematical relationship (Ⅰ), the calculated value of the aluminum contamination amount in the silicon wafer sample F1 after sterilization treatment in Example 1 was 8.5 mg / cm 3 , the calculated value of the aluminum contamination amount in the silicon wafer sample F2 after sterilization treatment in Example 2 was 6.1 mg / cm 3 , the calculated value of the aluminum contamination amount in the silicon wafer sample F3 after sterilization treatment in Example 3 was 5.2 mg / cm 3 , the calculated value of the aluminum contamination amount in the silicon wafer sample F4 after sterilization treatment in Example 4 was 5.0 mg / cm 3 .

[0097] Example 5

[0098] Preparation of sterilization packaging material:

[0099] Select a commercially available non-woven fabric W1 for sterilization made of polypropylene, with a size of 20 cm * 20 cm. Immerse the non-woven fabric in Nafion D521 dispersion for 60 s (the concentration of perfluorosulfonic acid-based polymer resin is 10 wt%), and dry it at 60 °C to obtain a polymer-modified aluminum adsorption sterilization packaging material E5. Among them, the thickness of the polymer-modified layer on one side of the sterilization packaging material E5 is 15 μm, and the density of the sterilization packaging material E5 is 0.2 g / cm 3 .

[0100] Determination of aluminum contamination amount in sterilized samples:

[0101] According to the method for determining the aluminum contamination amount in sterilized samples in Example 1, use ICP-MS to measure the response intensity of aluminum ions in the test solution, and according to the standard curve equation obtained in Example 1, the mass concentration S5 of aluminum ions in the diluted test solution is 5.5E-5 mg / mL. Calculate the aluminum content R5 adsorbed on the sterilization packaging material E5 after sterilization treatment through formula (2) as 5.5 mg / g. Calculate the aluminum concentration P5 adsorbed on the above sterilization packaging material through formula (3) as 1.10 mg / cm 3 . Use SIMS to measure the concentration distribution C5 of aluminum in the silicon wafer sample F5 after sterilization treatment, and use formula (1) to obtain the actual value of the aluminum contamination amount in F5, which is 5.7 mg / cm 2 .

[0102] Through calculation by the mathematical relationship (Ⅰ), the calculated value of the aluminum contamination amount in the silicon wafer sample F5 after sterilization treatment in Example 5 is 5.4 mg / cm 3 .

[0103] Comparative Example 1

[0104] According to the method for determining the aluminum contamination amount in sterilized samples in Example 1, use an unmodified ordinary polypropylene non-woven fabric W1 as the sterilization packaging material, and the results are shown in Table 1.

[0105] Comparative Example 2

[0106] According to the method for determining the aluminum contamination amount in sterilized samples in Example 1, use an unmodified ordinary PET non-woven fabric W2 as the sterilization packaging material, and the results are shown in Table 1.

[0107] Comparative Example 3

[0108] The preparation process of the sterilization packaging material of Example 1 is adopted, except that a commercially available non-woven fabric W1 for sterilization made of polypropylene with a size of 20 cm * 20 cm is selected. The non-woven fabric is immersed in sulfosalicylic acid (5 wt%) for 60 s and dried at 60 °C to obtain the modified material W3.

[0109] According to the method for measuring the aluminum contamination amount in the sterilized sample in Example 1, using the modified material W3 as the sterilization packaging material, the results are shown in Table 1.

[0110] Table 1

[0111]

[0112] In Table 1, the aluminum concentration in the sterilization packaging materials in Comparative Examples 1-4 is very low, approaching the detection limit.

[0113] It can be seen from the results in Table 1 that the sterilization packaging material prepared in the embodiment of the present invention has a good adsorption effect on the aluminum generated during the plasma sterilization process, and the value obtained by using the method for measuring the aluminum contamination amount provided by the present invention is very close to the actual contamination amount. Therefore, it can be used as an application for measuring the aluminum contamination amount caused by plasma sterilization.

[0114] The present invention has been described in detail above in combination with specific embodiments and exemplary examples, but these descriptions should not be construed as limiting the present invention. Those skilled in the art understand that without departing from the spirit and scope of the present invention, various equivalent substitutions, modifications or improvements can be made to the technical solutions and their implementation manners of the present invention, and these all fall within the scope of the present invention. The protection scope of the present invention is subject to the appended claims.

[0115] All publications, patent applications, patents and other references mentioned in this specification are hereby incorporated by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In case of conflict, the definitions in this specification shall prevail.

[0116] When this specification uses prefixes such as "known to those skilled in the art", "prior art" or similar terms to derive materials, substances, methods, steps, devices or components, etc., the objects derived by these prefixes cover those commonly used in the art at the time when this application is filed, but also include those that are not commonly used at present but will become commonly recognized in the art as suitable for similar purposes.

[0117] In the context of this specification, any matters or things not mentioned, except as clearly stated, directly apply those known in the art without any change.

Claims

1. A method for testing the amount of aluminum contamination in a sample after plasma sterilization, comprising: The sample is packaged with a sterilized packaging material and placed in a plasma sterilization chamber for sterilization treatment. After the sterilization treatment, the aluminum content P per unit volume in the sterilized packaging material is measured, and the aluminum contamination amount Q per unit area in the sterilized sample is obtained by calculation. The numerical values of P and Q satisfy the mathematical relationship (I): Q = 5.43P -0.15 Formula (I) The sterilized packaging material is a polymer-modified aluminum adsorbent material, and the polymer is selected from at least one of the polymers containing sulfonic acid groups.

2. The testing method according to claim 1, wherein the sterilized packaging material includes an aluminum adsorbent material support layer and a polymer-modified layer loaded on at least one surface of the support layer; and / or the polymer is selected from at least one of perfluorosulfonic acid resin and sulfonated polymer, preferably at least one of sulfonated polyether ketone and sulfonated polyethersulfone; and / or the ion exchange capacity of the polymer is 0.4 - 2.5 mmol / g, preferably 0.5 - 2.0 mmol / g, more preferably 0.9 - 2.0 mmol / g.

3. The test method according to claim 2, characterized in that, In the sterilized packaging material: the support layer is selected from at least one of polypropylene, polyethylene, and polyester, preferably a non-woven fabric of polypropylene and / or polyester material; and / or the thickness of the support layer is 0.1 - 1 mm, preferably 0.2 - 0.5 mm; and / or the thickness of the polymer-modified layer is 0.1 - 100 μm, preferably 0.5 - 50 μm.

4. The test method according to any one of claims 1 to 3, characterized in that The sterilized packaging material is obtained by the following preparation method: mixing the polymer with a solvent to obtain a dispersion liquid, and then coating it on at least one surface of the support layer, and drying to obtain the sterilized packaging material.

5. The testing method according to claim 4, wherein the solvent is selected from a mixed liquid of alcohol and water. Preferably, the alcohol is selected from at least one of methanol, ethanol, and n-butanol, and / or the volume ratio of alcohol to water in the solvent is (1 - 10):1; and / or the concentration of the polymer in the dispersion liquid is 1 - 20 wt%; and / or the coating method is dip coating; preferably, the dip coating time is 10 - 300 s, more preferably 30 - 120 s, further preferably 60 - 120 s; and / or the drying temperature is 40 - 80 °C.

6. The test method according to claim 1, wherein The method for establishing the mathematical relationship (I) includes: A) Measuring the aluminum concentration at different depths in the sample to obtain a distribution curve C0(x), where x is the depth; B) Packaging the sample with a first sterilized packaging material and placing it in a plasma sterilization chamber for sterilization; C) After the sterilization treatment, measuring the aluminum content P1 per unit volume of the first sterilized packaging material and the aluminum concentration at different depths in the sterilized sample to obtain a distribution curve C1(x), where x is the depth; D) Samples are packaged with different sterilized packaging materials, and steps B) and C) are repeated to obtain the aluminum content P per unit volume of different sterilized packaging materials after sterilization treatment. n In addition, the distribution curve C of the aluminum concentration at different depths in the sample after sterilization treatment is obtained. n (x), where x is the depth. The aluminum contamination amount Q per unit area of the sample after sterilization treatment is calculated by formula (1). n ; In formula (1), a is the depth value corresponding to the detection limit of the aluminum concentration in the sample after sterilization treatment, b is the depth value corresponding to the detection limit of the aluminum concentration in the sample without sterilization treatment, M Al represents the molar mass of aluminum, N A represents Avogadro's constant, and n is the number of different sterilization packaging materials; E) Establish a plane XY orthogonal coordinate system, input P1…P n numerical values on the X-axis, and input Q1…Q n numerical values on the Y-axis. Obtain the mathematical relationship formula (Ⅰ) between the Q numerical value and the P numerical value through fitting: Q = 5.43P -0.15 Formula (I).

7. The testing method according to claim 6, wherein the sample is selected from at least one of silicon, germanium, gallium nitride, silicon carbide, and gallium arsenide, preferably silicon; and / or in steps A), C), and D), the testing method for the aluminum concentration distribution in the sample is SIMS, AES, or XPS, preferably SIMS.

8. The testing method according to claim 6, characterized in that The aluminum content P per unit volume in the sterilized packaging material after the sterilization treatment in step C) and step D) n The test method includes: ⅰ) Prepare aluminum standard solutions with different concentrations, measure the response intensities of aluminum ions in the aluminum standard solutions with different concentrations by ICP-MS, and establish a standard curve; ii) Digest the sterilized packaging material adsorbed with aluminum after sterilization treatment so that the adsorbed aluminum is completely dissolved in the digestion solution and diluted to a volume V. n ; ⅲ) Then dilute the digested solution after volume fixation, and record the dilution factor as N to obtain the diluted test solution; ⅳ) Measure the response intensity of aluminum ions in the diluted test solution by ICP-MS, and obtain the mass concentration S of aluminum ions in the diluted test solution by substituting into the standard curve in step ⅰ) using the external standard method n ; ⅴ) Calculate the aluminum content R adsorbed on the sterilized packaging material after sterilization treatment through formula (2). n ; In formula (2), R n is the aluminum content adsorbed on the sterilized packaging material after sterilization, with the unit of mg / g; S n is the mass concentration of aluminum ions in the diluted test solution, with the unit of mg / mL; V n is the volume of the digested solution after volume fixation, with the unit of mL; N is the dilution factor; M n is the mass of the sterilized packaging material, with the unit of g; ⅵ) Calculate the aluminum concentration P per unit volume of the sterilized packaging material after sterilization treatment through formula (3). n : P n = R n × ρ n Equation (3) In formula (3), P n is the aluminum concentration per unit volume of the sterilized packaging material after sterilization, with the unit of mg / cm 3 ; R n is the aluminum content adsorbed on the sterilized packaging material after sterilization, with the unit of mg / g; ρ is the density of the sterilized packaging material, with the unit of g / cm 3 .

9. The test method according to claim 8, wherein in the step ⅰ), the solvent in the aluminum standard solution is selected from pure water or a pure aqueous nitric acid solution with a concentration not exceeding 5%; and / or, in the step ⅱ), the digested solution is a nitric acid solution. Preferably, the digested solution is a nitric acid solution with a mass concentration of 50-70%; and / or, In the step (ii), V n is 10 to 500 mL; and / or, in the step ⅲ), N is 10-1000.

10. Application of the test method according to any one of claims 1-9 in the test of aluminum contamination caused by plasma sterilization.

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