阅读说明：本技术 Ppdo缝线相对分子量的测定方法 (Method for measuring PPDO suture relative molecular weight ) 是由 彭健 施燕平 沈永� 许凯 吴长岩 薄晓文 于 2018-09-11 设计创作，主要内容包括：本发明提供了PPDO缝线相对分子量的测定方法。方法,包括下列步骤：用含0.005～0.015mol/L三氟乙酸钠的六氟异丙醇溶剂溶解PPDO缝线,得到样品溶液；采用凝胶色谱仪检测所述样品溶液中PPDO的分子量及分子量分布；所述检测的色谱条为：色谱柱：填料为聚二乙烯基苯,流动相：与所述样品溶液的溶剂相同,流速：0.5～1.0mL/min,柱温：20～45℃,进样量：40～60μL。本发明能够准确、高效的测定PPDO缝线分子量及其分布,对于PPDO生产及其质量控制都具有重要意义。(The invention provides a method for measuring the relative molecular weight of PPDO suture. The method comprises the following steps: dissolving a PPDO suture line by using a hexafluoroisopropanol solvent containing 0.005-0.015 mol/L of sodium trifluoroacetate to obtain a sample solution; detecting the molecular weight and molecular weight distribution of PPDO in the sample solution by adopting a gel chromatograph; the chromatographic strip for detection is as follows: a chromatographic column: the filler is polydivinylbenzene, and the mobile phase: same solvent as the sample solution, flow rate: 0.5-1.0 mL/min, column temperature: 20-45 ℃, sample injection amount: 40-60 mu L. The method can accurately and efficiently measure the PPDO suture molecular weight and the distribution thereof, and has important significance for PPDO production and quality control thereof.)

A method for measuring the relative molecular weight of PPDO suture, which is characterized by comprising the following steps:

dissolving a PPDO suture line by using a hexafluoroisopropanol solvent containing 0.005-0.015 mol/L of sodium trifluoroacetate to obtain a sample solution;

detecting the molecular weight and molecular weight distribution of PPDO in the sample solution by adopting a gel chromatograph;

the chromatographic strip for detection is as follows:

a chromatographic column: the filler is polydivinylbenzene, and the filler is polydivinylbenzene,

mobile phase: the same solvent as the sample solution,

flow rate: 0.5 to 1.0mL/min,

column temperature: at the temperature of 20-45 ℃,

sample introduction amount: 40-60 mu L.

2. A PPDO suture relative molecular weight determination method according to claim 1, characterized in that said solvent is hexafluoroisopropanol containing 0.001-0.015 mol/L of sodium trifluoroacetate, preferably 0.001-0.013 mol/L of sodium trifluoroacetate.

3. The method for determining the relative molecular weight of a PPDO suture according to claim 1, characterized in that the standard used in the detection is polymethyl methacrylate.

4. A PPDO suture relative molecular weight determination method according to claim 3, characterized in that the standard substance used in the detection is polymethyl methacrylate with a molecular weight of 800-120 ten thousand.

5. A method for determining the relative molecular weight of a PPDO suture according to claim 1, wherein said detection is within 0.4-1 hour, preferably within 0.5-1 hour after said dissolution.

6. A PPDO suture relative molecular weight determination method according to claim 1, characterized in that said sample solution is also filtered, preferably with a 0.22 μm filter, before said detection.

7. The method for determining the relative molecular weight of PPDO suture of claim 1, wherein the chromatographic column is: the filler was polydivinylbenzene, 300mm by 7.8mm in size.

8. A PPDO suture relative molecular weight determination method according to claim 1, characterized in that said flow rate is: 0.8-1.0 mL/min.

9. The method for determining the relative molecular weight of a PPDO suture of claim 1, wherein the column temperature: 30-45 ℃.

10. The method for measuring the relative molecular weight of a PPDO suture according to claim 1, characterized in that the sample volume: 50-60 mu L.

Technical Field

The invention relates to the technical field of analytical chemistry, in particular to a method for measuring the relative molecular weight of PPDO suture.

Background

PPDO (poly (p-dioxanone)), which belongs to aliphatic polyether ester, is a degradable biological material, has excellent hydrolyzability, biodegradability, biocompatibility and biological absorbability, excellent flexibility and tensile strength, can be used as a medical absorbable surgical suture material, and has wide application. The relative molecular weight and the distribution of the polymer are one of the most basic parameters of the high molecular material, and are closely related to the use performance and the processing performance of the high molecular material. The relative quality is too low, the mechanical strength and toughness of the material are poor, and the material has no application value. The relative mass is too high and the melt viscosity increases, making processing difficult. Because PPDO suture is difficult to dissolve in a conventional solvent, molecular weight measurement is rarely reported at home and abroad, most of documents are characterized by the viscosity-average molecular weight, and the performance index of the suture cannot be directly reflected.

In view of the above, the present invention is particularly proposed.

Disclosure of Invention

The invention aims to provide a method for measuring the relative molecular weight of PPDO suture, which can accurately and efficiently measure the molecular weight and the distribution of the PPDO suture and has important significance on PPDO production and quality control thereof.

In order to achieve the above purpose, the invention provides the following technical scheme:

the method for measuring the relative molecular weight of the PPDO suture comprises the following steps:

dissolving a PPDO suture line by using a hexafluoroisopropanol solvent containing 0.005-0.015 mol/L of sodium trifluoroacetate to obtain a sample solution;

detecting the molecular weight and molecular weight distribution of PPDO in the sample solution by adopting a gel chromatograph;

the chromatographic strip for detection is as follows:

a chromatographic column: the filler is polydivinylbenzene, and the filler is polydivinylbenzene,

mobile phase: the same solvent as the sample solution,

flow rate: 0.5 to 1.0mL/min,

column temperature: at the temperature of 20-45 ℃,

sample introduction amount: 40-60 mu L.

The method disclosed by the invention has the advantages that the weight average molecular weight and the distribution of the PPDO suture are directly measured by using a gel chromatograph, the accuracy is high, the repeatability is strong, the method can be used for measuring the PPDO suture with the molecular weight of 800-1190000 and the standard fitting parameter 0.99966, the molecular weight and the distribution of the PPDO suture can be accurately and efficiently measured, and the method has important significance for PPDO production and quality control.

According to the invention, hexafluoroisopropanol containing 0.005-0.015 mol/L sodium trifluoroacetate is used as a solvent, so that the problem of difficult PPDO suture dissolution is solved.

The invention adopts the gel chromatography with specific conditions to detect the molecular weight and the molecular weight distribution of PPDO, and solves the problem that the molecular weight can not be directly reflected.

The invention discovers that the solubility and the stability of PPDO suture can be improved by adding a small amount of sodium trifluoroacetate into hexafluoroisopropanol. Sodium trifluoroacetate can be selected from any concentration within 0.005-0.015 mol/L, such as 0.005mol/L, 0.006mol/L, 0.007mol/L, 0.008mol/L, 0.009mol/L, 0.010mol/L, 0.011mol/L, 0.013mol/L, 0.015mol/L and the like.

The flow rate of the present invention may be any value within 0.5 to 1.0mL/min, for example, 0.5mL/min, 0.6mL/min, 0.7mL/min, 0.8mL/min, 0.9mL/min, 1.0mL/min, etc.

The column temperature of the present invention may be any value within 20 to 45 ℃, for example, 20 ℃, 25 ℃, 30 ℃, 35 ℃, 40 ℃, 45 ℃ or the like.

The sample injection amount of the present invention may be any value within 40 to 60. mu.L, for example, 40. mu.L, 45. mu.L, 50. mu.L, 55. mu.L, 60. mu.L, etc.

Through screening, the method is higher in accuracy and higher in repeatability when the following chromatographic conditions are adopted:

preferably, the chromatographic column is: the filler was polydivinylbenzene, 300mm by 7.8mm in size.

Preferably, the flow rates are: 0.8-1.0 mL/min.

Preferably, the column temperature: 30-45 ℃.

Preferably, the sample size: 50-60 mu L.

In addition, other detection conditions may be further optimized, as follows.

Preferably, the solvent is hexafluoroisopropanol containing 0.001 to 0.015mol/L of sodium trifluoroacetate, and preferably 0.001 to 0.013mol/L of sodium trifluoroacetate.

Preferably, the standard substance used in the detection is polymethyl methacrylate.

The invention researches and finds that the polymethyl methacrylate (PMMA) is well dissolved in hexafluoroisopropanol, the molecular weight of the PMMA is only changed by 2.6 percent after the PMMA is dissolved in hexafluoroisopropanol for 4 hours and 24 hours, and the stability is good, so that the polymethyl methacrylate (PMMA) is used as a standard substance and has higher detection accuracy and sensitivity.

The correlation coefficient of a standard curve which is fitted by taking PMMA as a standard can reach above 0.9996.

Preferably, the standard substance used in the detection is polymethyl methacrylate with the molecular weight of 800-120 ten thousand.

Preferably, the detection is performed within 0.4 to 1 hour after the dissolution, and preferably within 0.5 to 1 hour.

Since the decrease in the Mw value of the PPDO suture with increasing dissolution time, especially after 1 hour, was very significant, the 24h molecular weight was only 36.16% of the 0.5h molecular weight. Therefore, such samples cannot be analyzed by dissolving and standing overnight. The decrease in the value of Mn is more gradual.

Preferably, the sample solution is also filtered, preferably with a 0.22 μm filter, prior to the detection.

In summary, compared with the prior art, the invention achieves the following technical effects:

(1) the gel chromatograph is used for directly measuring the weight average molecular weight and the distribution of the PPDO suture, the accuracy is high, the repeatability is strong, the method can be used for measuring the PPDO suture with the molecular weight of 800-1190000, the standard fitting parameter 0.99966 can accurately and efficiently measure the molecular weight and the distribution of the PPDO suture, and the method has important significance for PPDO production and quality control.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a comparison chromatogram of PMMA provided in example 1 of the present invention in hexafluoroisopropanol for 4 hours versus 24 hours;

FIG. 2 is a chromatogram of different molecular weight standards provided in example 1 of the present invention;

FIG. 3 is a fitting curve provided in example 1 of the present invention;

FIG. 4 is a graph of weight average molecular weight of a sample as a function of dissolution time as provided in example 1 of the present invention.

Detailed Description

The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and the detailed description, but those skilled in the art will understand that the following described embodiments are some, not all, of the embodiments of the present invention, and are only used for illustrating the present invention, and should not be construed as limiting the scope of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The core of the following examples of the invention lies in the sample treatment process and chromatographic conditions, as detailed below.

The method for measuring the relative molecular weight of the PPDO suture comprises the following steps:

dissolving a PPDO suture line by using a hexafluoroisopropanol solvent containing 0.005-0.015 mol/L of sodium trifluoroacetate to obtain a sample solution;

detecting the molecular weight and molecular weight distribution of PPDO in the sample solution by adopting a gel chromatograph;

the chromatographic strip for detection is as follows:

a chromatographic column: the filler is polydivinylbenzene, and the filler is polydivinylbenzene,

mobile phase: the same solvent as the sample solution,

flow rate: 0.5 to 1.0mL/min,

column temperature: at the temperature of 20-45 ℃,

sample introduction amount: 40-60 mu L.

Different embodiments further optimize the detection conditions on the basis of the above, specifically as follows.

Preferably, the solvent is hexafluoroisopropanol containing 0.001 to 0.015mol/L of sodium trifluoroacetate, and preferably 0.001 to 0.013mol/L of sodium trifluoroacetate.

Preferably, the standard substance used in the detection is polymethyl methacrylate.

Preferably, the standard substance used in the detection is polymethyl methacrylate with the molecular weight of 800-120 ten thousand.

Preferably, the detection is performed within 0.4 to 1 hour after the dissolution, and preferably within 0.5 to 1 hour.

Preferably, the sample solution is also filtered, preferably with a 0.22 μm filter, prior to the detection.

Preferably, the chromatographic column is: the filler was polydivinylbenzene, 300mm by 7.8mm in size.

Preferably, the flow rates are: 0.8-1.0 mL/min.

Preferably, the column temperature: 30-45 ℃.

Preferably, the sample size: 50-60 mu L.