Method for detecting content of multi-component leached substances in intraocular lens by gas chromatography

Abstract

The invention discloses a method for detecting the content of multi-component leached substances of an intraocular lens by using a gas chromatography, which comprises the following steps: respectively weighing reference substances of the leached substances of the intraocular lens, and preparing a series of standard solutions with different concentrations for each reference substance of the leached substances by using an organic solvent; carrying out temperature programming elution on the standard solutions of the reference substances of the leached substances by adopting a gas chromatographic method to obtain chromatograms of the leached substances corresponding to different retention times, and drawing a standard curve of each standard solution according to the concentration-peak area; extracting an intraocular lens sample to be detected to obtain a test solution of a multi-component leached substance of the sample; performing gas chromatography detection on the test solution to obtain a sample chromatogram; and according to a sample chromatogram and a result obtained by the standard solution, carrying out qualitative and quantitative analysis on the leached substance components in the test solution by using an external standard method. The method can be used for qualitatively and quantitatively detecting various components at one time, and has the characteristics of simplicity, convenience, rapidness, high efficiency, sensitivity and accuracy.

Description

Technical Field

[0001] The invention relates to the technical field of analysis and detection, and in particular to a method for detecting the content of multi-component leachable substances in an artificial lens by using a gas chromatography method. Background Art

[0002] Intraocular lens, also known as IOL, refers to a special lens made of artificial synthetic materials. It is mainly used to replace the diseased lens in cataract surgery and is one of the most widely used implantable medical device products in the world. With the aging of the population, the number of patients undergoing cataract removal combined with intraocular lens implantation has also increased year by year. As the user population continues to expand, in order to meet the specific needs of different patients, intraocular lens materials have shown diversified development, mainly including silicone gel materials with high thermal stability, hydrophobic acrylic materials with long-term stability and high mechanical strength, and hydrophilic acrylic materials with good hydrophilicity and easy folding. Strong stability, high optical quality and excellent biocompatibility are the fundamental guarantees for improving patients' postoperative visual quality, and biocompatibility is more important than the other two. The safety of intraocular lens manufacturing materials is closely related to the user's eye health and has received special attention.

[0003] At present, the industry standard "YY / T 0290.5-2008-Ophthalmic Optics Intraocular Lenses Part 5: Biocompatibility" and the national standard "GB / T 16886.17-2005-Biological Evaluation of Medical Devices Part 17 Establishment of Permissible Limits of Leachables" stipulate the safety evaluation of leachables in intraocular lenses and require the establishment of safety limits for contact with the human body. The leachable content of medical devices is one of the important indicators for evaluating biocompatibility and has also been a focus of attention in the review process of medical devices in recent years. Therefore, the analysis of the residual amount of leachable components in intraocular lenses is a prerequisite for the safety study of intraocular lenses. It also helps to evaluate intraocular lens materials and determine preclinical inspection procedures. It is a key requirement for the production and development of intraocular lenses.

[0004] The current IOL standards lack a clear method for detecting leachables, which poses a major challenge to product safety supervision. Although some scholars have conducted research, there are few reports and they mainly focus on testing a single component, which takes a long time to test. In particular, research on multi-component leachables is very scarce. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a method for detecting the content of multi-component leachable substances in artificial lenses by gas chromatography, which can simultaneously detect the content of multi-component leachable substances in artificial lenses based on gas chromatography, and the method is simple, rapid and highly sensitive.

[0006] The present invention discloses a method for detecting the content of multi-component leachable substances in an intraocular lens by gas chromatography, comprising:

[0007] Step 1, weighing the intraocular lens leachable reference substances respectively, and then preparing a series of standard solutions of different concentrations for each leachable reference substance with an organic solvent;

[0008] Step 2: Performing programmed temperature elution on the series of standard solutions of each leachable reference substance prepared in step 1 by gas chromatography to obtain leachable chromatograms corresponding to different retention times, and drawing a standard curve of each standard solution according to concentration-peak area;

[0009] Step 3, extracting the artificial lens sample to be tested to obtain a test solution of a multi-component leachable substance of the artificial lens sample to be tested;

[0010] Step 4: Perform gas chromatography on the test solution obtained in step 3 to obtain a sample chromatogram; and qualitatively and quantitatively analyze the leachable components in the test solution using an external standard method based on the sample chromatogram and the result obtained in step 2.

[0011] As a further improvement of the present invention, the leachable substances of the intraocular lens include 6 or more of butyl acrylate (BA), methyl methacrylate (MMA), vinyl toluene (MST), 2-hydroxyethyl methacrylate (HEMA), ethylene glycol dimethacrylate (EGDMA), 2-ethoxyethyl methacrylate (EOEMA), lauryl methacrylate (LMA), 2-phenoxyethyl acrylate (PEAA), 2-phenylethyl methacrylate (PEMA) and 2-phenylethyl acrylate (PEA).

[0012] As a further improvement of the present invention, in step 1, the preparation method of the multi-component mixed standard solution is:

[0013] A mixed standard solution containing a target detection object reference substance is prepared with an organic solvent, and the mixed standard solution is diluted with the organic solvent to obtain a series of standard solutions with a concentration ranging from 1 to 20 μg / mL.

[0014] As a further improvement of the present invention, in step 1, the organic solvent is one or more of methanol, ethanol, isopropanol, acetonitrile, acetone, n-hexane and dichloromethane.

[0015] As a further improvement of the present invention, in step 2, the test conditions of gas chromatography are:

[0016] a) Chromatographic column: DB-1 capillary column, 30m×0.32mm, 0.25μm film thickness; constant flow mode, column flow rate: 1.0mL / min;

[0017] b) Inlet temperature: 250°C; hydrogen: air = 35:350 mL / min; tail gas flow rate: 25 mL / min; injection mode: split ratio 2:1; injection volume: 1 μL;

[0018] c) Heating program: 80°C, hold for 4 min, increase the temperature to 280°C at a rate of 10°C / min, hold for 4 min;

[0019] d) Detector: hydrogen flame ionization detector, temperature: 300°C;

[0020] e) Carrier gas: high-purity nitrogen, purity ≥ 99.999%.

[0021] As a further improvement of the present invention, in step 3, the extraction method is: performing Soxhlet extraction on the artificial lens sample to be tested, and the obtained extract is the test solution; the solvent for the Soxhlet extraction is acetonitrile, and the amount of acetonitrile is 50 to 300 mL; the time of the Soxhlet extraction is 4 to 24 hours, and the number of the artificial lens samples to be tested is 10 to 20 pieces.

[0022] As a further improvement of the present invention, in step 4, the method of using the external standard method to qualitatively and quantitatively analyze the leachable components in the test solution is as follows: comparing the retention time of each peak in the sample chromatogram with the leachable chromatogram in step 2 to determine the type of leachable corresponding to each peak; and then calculating the content of the leachable in the test solution based on the peak area and the standard curve in step 2.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The invention adopts gas chromatography to perform programmed temperature elution, and qualitatively and quantitatively analyzes multi-component leachable substances by an external standard method; that is, firstly, a reference solution is detected to determine the types of leachable substances corresponding to each retention time, a series of concentrations of a multi-component mixed standard solution is prepared, and a relationship curve (i.e., a standard curve) between the concentration of the leachable substances and the peak area is obtained; finally, a test solution is detected, and the leachable substance components in the test solution are qualitatively and quantitatively analyzed by an external standard method in combination with the obtained spectrum, the retention time of the reference substance and the standard curve; the method of the invention can complete the qualitative and quantitative analysis of multiple components at one time, and has the characteristics of being simple, rapid, efficient, sensitive and accurate.

[0025] By optimizing the test conditions, the present invention can not only detect the content of multi-component leachables at the same time to ensure the safety of clinical implantation of artificial lenses, but also improve the detection efficiency, comply with the technical review guidelines for verification and confirmation of registration of known leachables determination methods for medical devices, and the linearity, quantitative limit, detection limit, precision, accuracy, etc. meet the requirements of methodological verification; the method has been applied to the detection and analysis of the content of leachables in artificial lens products, and can be widely used in the supervision of the content of leachables in artificial lens products and product quality control. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The present invention discloses a flow chart of a method for detecting the content of multi-component leachable substances in an intraocular lens by gas chromatography;

[0027] Figure 2 The gas chromatogram obtained from the multi-component mixed standard solution in Example 1 of the present invention: wherein 1 is butyl acrylate (BA), 2 is 2-ethoxyethyl methacrylate (EOEMA), 3 is ethylene glycol dimethacrylate (EGDMA), 4 is 2-phenylethyl acrylate (PEA), 5 is 2-phenyl methacrylate (PEMA), and 6 is 2-phenoxyethyl acrylate (PEAA);

[0028] Figure 3 This is the gas chromatogram obtained from the test solution in Example 1 of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0031] like Figure 1As shown, the present invention provides a method for detecting the content of multi-component leachable substances in an intraocular lens by gas chromatography, which can complete the qualitative and quantitative detection of multi-component leachable substances in an intraocular lens at one time, and the leachable substances in the intraocular lens include butyl acrylate (BA), methyl methacrylate (MMA), vinyl toluene (MST), 2-hydroxyethyl methacrylate (HEMA), ethylene glycol dimethacrylate (EGDMA), 2-ethoxyethyl methacrylate (EOEMA), lauryl methacrylate (LMA), 2-phenoxyethyl acrylate (PEAA), 2-phenyl methacrylate (PEMA) and 2-phenylethyl acrylate (PEA) Six or more; the method comprises:

[0032] Step 1, weigh the artificial lens leachable substance reference substance separately, prepare a mixed standard solution containing the target detection substance reference substance with an organic solvent, dilute the mixed standard solution with the organic solvent to obtain a series of standard solutions with a concentration in the range of 1 to 20 μg / mL; wherein the organic solvent is one or more of methanol, ethanol, isopropanol, acetonitrile, acetone, n-hexane and dichloromethane.

[0033] Step 2: Performing programmed temperature elution on the series of standard solutions of each leachable reference substance prepared in step 1 by gas chromatography to obtain leachable chromatograms corresponding to different retention times, and drawing a standard curve of each standard solution based on concentration-peak area; wherein the test conditions of the gas chromatography are:

[0034] a) Chromatographic column: DB-1 capillary column, 30m×0.32mm, 0.25μm film thickness; constant flow mode, column flow rate: 1.0mL / min;

[0035] b) Inlet temperature: 250°C; hydrogen: air = 35:350 mL / min; tail gas flow rate: 25 mL / min; injection mode: split ratio 2:1; injection volume: 1 μL;

[0036] c) Heating program: 80°C, hold for 4 min, increase the temperature to 280°C at a rate of 10°C / min, hold for 4 min;

[0037] d) Detector: hydrogen flame ionization detector, temperature: 300°C;

[0038] e) Carrier gas: high-purity nitrogen, purity ≥ 99.999%.

[0039] Step 3, performing Soxhlet extraction on the artificial lens sample to be tested, and the obtained extract is the test solution of the multi-component leachable substance of the artificial lens sample to be tested; wherein, the solvent for Soxhlet extraction is acetonitrile, and the amount of acetonitrile is 50-300mL; the time of Soxhlet extraction is 4-24h, and the number of artificial lens samples to be tested is 10-20 pieces.

[0040] Step 4: Perform gas chromatography on the test solution obtained in step 3 by the same adjustment as step 2 to obtain a sample chromatogram; according to the sample chromatogram and the result obtained in step 2 (chromatogram and standard curve of the mixed standard solution), the leachable components in the test solution are qualitatively and quantitatively determined using the external standard method; wherein the specific qualitative and quantitative methods are:

[0041] Compare the retention time of each peak in the sample chromatogram with the leachable substance chromatogram in step 2 to determine the type of leachable substance corresponding to each peak; then calculate the content of leachable substance in the test solution based on the peak area and the standard curve in step 2.

[0042] Example 1

[0043] like Figure 1 As shown, the present invention provides a method for detecting the content of multi-component leachable substances in an intraocular lens by gas chromatography, comprising:

[0044] S1. Prepare standard solution of intraocular lens leachables:

[0045] Use a 1 / 100,000 balance to accurately weigh 0.1 g of artificial lens leachable material reference substances: BA, EOEMA, EGDMA, PEA, PEMA and PEAA, respectively, add them into 4 100 ml volumetric flasks, dissolve and make up the volume with acetonitrile to prepare a mother solution with a concentration of 1000 μg / ml; then take 1 ml of the above mother solution into 1 10 ml volumetric flask, make up the volume with acetonitrile to prepare a mixed standard solution with a concentration of 100 μg / ml; then use the same method to further accurately dilute each artificial lens leachable material into a gradient mixed standard solution with concentrations of 1 μg / ml, 2.5 μg / ml, 5 μg / ml, 10 μg / ml, 15 μg / ml and 20 μg / ml.

[0046] S2. Draw a standard curve for intraocular lens leachables:

[0047] The standard solution prepared by S1 was subjected to programmed temperature elution by gas chromatography, wherein the chromatographic column was a DB-1 capillary column, 30m×0.32mm, 0.25μm film thickness; constant flow mode, column flow rate: 1.0mL / min; injection port temperature: 250℃; hydrogen: air = 35:350mL / min, that is, hydrogen is 35mL / min, air is 350mL / min; tail gas flow rate: 25mL / min; injection mode: split injection, split ratio 2:1; injection volume: 1μL; heating program: 80℃, hold for 4min, heat to 280℃ at a rate of 10℃ / min, hold for 4min; detector: hydrogen flame ionization detector, temperature: 300℃; carrier gas: high-purity nitrogen, purity ≥99.999%. After the above programmed temperature elution, the following was obtained: Figure 2 Chromatogram of the standard solution is shown.

[0048] The detection limit (LOD, LOD = 3S / N) of the method was taken as three times the signal-to-noise ratio S / N, and the quantification limit (LOQ, LOQ = 10S / N) of the method was taken as ten times the signal-to-noise ratio S / N, and the detection limit and quantification limit of each leachable substance in acetonitrile were calculated in combination with the added matrix. The relevant parameters of the standard curve of each leachable substance based on the above matrix, LOD and LOQ related information are shown in Table 1.

[0049] Table 1 Standard curve equations and related parameters of BA, EOEMA, EGDMA, PEA, PEMA and PEAA standard solutions

[0050]

[0051] Depend on Figure 2 As can be seen from Table 1, the present invention can achieve rapid detection of multi-component leachables within 28 minutes with high detection sensitivity. The peak area and concentration show a good linear relationship in the respective concentration ranges, and the linear correlation coefficient R is not less than 0.99. The detection limit of the method is 0.08-0.14 μg / ml.

[0052] S3. Precision and accuracy test:

[0053] Repeatability was used to examine precision, and recovery was used to evaluate the accuracy of the method. Standard solutions were accurately added to blank matrices that did not contain the components to be tested to obtain spiked samples at three different concentration levels (low, medium, and high, see actual concentration for details). Each concentration level was repeated 3 times, and the recovery and relative standard deviation (RSD) values ​​were calculated. The results are shown in Table 2.

[0054] Table 2 Average spiked recoveries and precisions of BA, EOEMA, EGDMA, PEA, PEMA and PEAA (n=3)

[0055]

[0056] According to Table 2, the relative standard deviation is <6%, indicating that the test method has good repeatability and high precision. Through the spike test, the recovery rates of the six leachable substances were between 90% and 115%, indicating that the test method has high accuracy.

[0057] S4. Prepare the test solution of the intraocular lens sample to be tested:

[0058] Take 10 artificial lenses and perform Soxhlet extraction on them using a Soxhlet extraction apparatus. The solvent used for the Soxhlet extraction is acetonitrile, the amount of acetonitrile is 100 mL, and the Soxhlet extraction time is 6 h. After the extraction is completed, the extract is concentrated to 10 ml as the test solution.

[0059] S5. Sample testing:

[0060] 1 μL of the test solution obtained in S4 is directly injected into the gas chromatograph and tested according to the above instrument conditions; the type of leachable substance corresponding to each peak is obtained by comparing the retention time with the reference substance, and then the content of the leachable substance of each component is calculated based on the fitting curve of each leachable substance reference substance (i.e., the standard curve obtained in S2). The calculation result is as follows: Figure 3 As shown. The test results show that the leachable substances in the samples to be tested include PEAA, with a content of 9.46μg / ml, a spike recovery rate of 105.5%, and a relative standard deviation of 3.9%. It can be seen that the method of the present invention has high detection efficiency, good repeatability, accuracy and reliability.

[0061] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for detecting the content of multi-component leachable substances in intraocular lenses by gas chromatography, characterized in that: include: Step 1, weighing the intraocular lens leachable reference substances respectively, and then preparing a series of standard solutions of different concentrations for each leachable reference substance with an organic solvent; Step 2: Performing programmed temperature elution on the series of standard solutions of each leachable reference substance prepared in step 1 by gas chromatography to obtain leachable chromatograms corresponding to different retention times, and drawing a standard curve of each standard solution according to concentration-peak area; Step 3, extracting the artificial lens sample to be tested to obtain a test solution of a multi-component leachable substance of the artificial lens sample to be tested; Step 4: Perform gas chromatography on the test solution obtained in step 3 to obtain a sample chromatogram; and qualitatively and quantitatively analyze the leachable components in the test solution using an external standard method based on the sample chromatogram and the result obtained in step 2.

2. The method according to claim 1, characterized in that The leachable substances of the intraocular lens include 6 or more of butyl acrylate, methyl methacrylate, vinyl toluene, 2-hydroxyethyl methacrylate, ethylene glycol dimethacrylate, 2-ethoxyethyl methacrylate, lauryl methacrylate, 2-phenoxyethyl acrylate, 2-phenylethyl methacrylate and 2-phenylethyl acrylate.

3. The method according to claim 1, characterized in that In step 1, the preparation method of the multi-component mixed standard solution is: A mixed standard solution containing a target detection object reference substance is prepared with an organic solvent, and the mixed standard solution is diluted with the organic solvent to obtain a series of standard solutions with a concentration ranging from 1 to 20 μg / mL.

4. The method according to claim 1, characterized in that In step 1, the organic solvent is one or more of methanol, ethanol, isopropanol, acetonitrile, acetone, n-hexane and dichloromethane.

5. The method according to claim 1, characterized in that In step 2, the test conditions of gas chromatography are: a) Chromatographic column: DB-1 capillary column, 30m×0.32mm, 0.25μm film thickness; constant flow mode, column flow rate: 1.0mL / min; b) Inlet temperature: 250°C; hydrogen: air = 35:350 mL / min; tail gas flow rate: 25 mL / min; injection mode: split injection, split ratio 2:1; injection volume: 1 μL; c) Heating program: 80°C, hold for 4 min, increase the temperature to 280°C at a rate of 10°C / min, hold for 4 min; d) Detector: hydrogen flame ionization detector, temperature: 300°C; e) Carrier gas: high-purity nitrogen, purity ≥ 99.999%.

6. The method according to claim 1, characterized in that In step 3, the extraction method is: performing Soxhlet extraction on the artificial lens sample to be tested, and the obtained extract is the test solution; the solvent used for the Soxhlet extraction is acetonitrile, and the amount of acetonitrile is 50 to 300 mL; the time of the Soxhlet extraction is 4 to 24 hours, and the number of the artificial lens samples to be tested is 10 to 20 pieces.

7. The method according to claim 1, characterized in that In step 4, the method of using the external standard method to qualitatively and quantitatively analyze the leachable components in the test solution is as follows: comparing the retention time of each peak in the sample chromatogram with the leachable chromatogram in step 2 to determine the type of leachable corresponding to each peak; and then calculating the content of the leachable in the test solution based on the peak area and the standard curve in step 2.

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