CN104458984A - Method for determining polymer in cephalosporins drug - Google Patents

Abstract

The invention belongs to the field of the analysis on a drug, and particularly relates to a method for determining a polymer in a cephalosporins drug. The gel chromatography is adopted, and the content of the polymer in the cephalosporins drug is determined by adopting an external standard method. The chromatographic conditions are stated as follows: TSK G2000SW *1 is adopted for a gel chromatographic column as stuffing; a mixture of 5mmol/L phosphate buffer solution [formed by mixing a 5mmol/L disodium hydrogen phosphate solution and a 5mmol/L sodium dihydrogen phosphate solution in a ratio of (20 to 80): (80 to 20), and the pH value is adjusted to 7.0 by utilizing 0.1mol/L phosphoric acid] and acetonitrile in a ratio of (95 to 50): (5 to 50) are adopted as a flow phase; the detection wavelength is 254nm; the flow rate is 0.6 to 2.0 ml/min; the column temperature is 20 to 35 DEG C. The method can be applied to the cephalosporins drug which is insoluble in ordinary organic solvent with a low boiling point or water and is high in accuracy, good in repeatability, simple and convenient.

Description

A kind of method measuring polymkeric substance in Cephalosporins

Technical field

The invention belongs to Pharmaceutical Analysis field, relate to a kind of method measuring polymkeric substance in Cephalosporins.

Background technology

Semisynthetic antibiotics containing cephem in cephalosporins cephalosporins. molecule.Once cephaloridnum was translated.Belong to beta-lactam antibiotic, be the derivant of the 7-amino-cephalosporanic acid (7-ACA) in beta-lactam antibiotic, therefore they have similar bactericidal mechanism.This class medicine can destroy the cell membrane of bacterium, and in sterilization breeding period.Strong to the selection index system of bacterium, and toxicity is not almost had to people, the advantage such as have that has a broad antifungal spectrum, antibacterial action are strong, penicillin resistant enzyme, allergic reaction are rare compared with penicillins.So be that a class is efficient, the important microbiotic of low toxicity, wide clinical application.Allergic reaction is modal bad reaction.Common fash, nettle rash, drug rash and hypereosinophilic etc.There is anaphylactic shock once in a while.Research in recent years finds that the superpolymer impurity of cephalosporins and allergic reaction have direct relation, and therefore pharmacopoeia of each country all carries out the inspection of polymkeric substance to part cephalosporin medicament, with the superpolymer produced in production control process and storage process.

Current Chinese Pharmacopoeia adopts sephadex to be that filler is analyzed for the method measuring polymkeric substance.The shortcoming of the method needs existing packing, length consuming time and repeatability bad, the number of plates is low, needs repeatedly to load the system suitability requirement that just can reach pharmacopeia; And this method needs specially to join low pressure liquid phase to be analyzed.As used the sephadex column of finished product, coordinate high pressure liquid phase, better, the number of plates is desirable, but chromatographic column is fragile, the life-span is short for result repeatability.Use sephadex method need with two kinds of mobile phases, analyze monomer and polymkeric substance respectively, round of visits be long; The method can not to dimer, tripolymer even polymer be separated.The present invention proposes a kind of new method, and use the gel chromatographic columns that TSK G2000SW xl is filler, only use a kind of mobile phase, analysis time is short, and repeatability is high, and precision is good, and the chromatographic column life-span is long, and dimer, tripolymer and polymer degree of separation are good.

Summary of the invention:

The object of the invention is to the deficiency overcoming existing pharmacopeia data, provide a kind of chromatographic column of new packing to measure the exclusion chromatography of polymkeric substance liquid phase in Cephalosporins, thus realize the mensuration of polymkeric substance in Cephalosporins.

A kind of method measuring polymkeric substance in Cephalosporins of the present invention is the gel chromatographic columns that is filler with TSK G2000SW xl, to cushion mixed solution that saline solution and organic phase form according to a certain ratio for mobile phase, adopts exclusion chromatography to measure.

Wherein the gel chromatographic columns of assay method described above is for filler with TSK G2000SW xl.

Organic phase in mobile phase of the present invention is acetonitrile.

Buffer salt solution of the present invention is phosphate buffer, primarily of sodium hydrogen phosphate and sodium dihydrogen phosphate composition.

The concentration of buffer salt solution of the present invention is 5mmol/L.

In buffer salt solution of the present invention, the concentration of disodium phosphate soln is the concentration of 5mmol/L and sodium dihydrogen phosphate is 5mmol/L.

In buffer salt solution of the present invention, the volume ratio of disodium phosphate soln-sodium dihydrogen phosphate is 20 ~ 80:80 ~ 20, is preferably 60 ~ 70:40 ~ 30.

The pH value of buffer salt solution of the present invention is 7.0.

The volume ratio of buffer salt solution-organic phase of the present invention is 95 ~ 50:5 ~ 50.Be preferably 90 ~ 95:10 ~ 5.

Described method of the present invention is external standard method.Its concrete steps are as follows:

1) typical curve and the range of linearity: get the known Cefdinir reference substance of content for contrast, gradient dilution, with phosphate buffered solution and acetonitrile for mobile phase, cross chromatographic column, detect under determined wavelength, record chromatogram, obtains the parameter such as peak height and peak area, obtains typical curve and the range of linearity;

2) external standard method Cefdinir polymer content: select suitable concentration in the range of linearity, preparation contrast solution and sample solution, measure under selected chromatographic condition, record chromatogram, calculate with phase optical parameter by external standard method, obtain the content of Cefdinir polymkeric substance.

Assay method of the present invention, can realize by the following method:

(1) preparation of solution: accurate weighing test sample and Cefdinir reference substance, add appropriate phosphate buffer, after dissolving, thin up, shakes up, as need testing solution and Cefdinir reference substance solution.

(2) setting of instrument condition: the UV detect wavelength of gel permeation chrommatograph is 254nm, the flow velocity 0.6 ~ 2.0ml/min of mobile phase; The post case temperature 20 ~ 35 DEG C of chromatographic column.

(3) sample solution in accurate measuring (1), is injected in coagulant liquid chromatography, completes the mensuration to polymeric impurities in Cephalosporins.

Wherein chromatographic condition is:

Coagulant liquid chromatography: wherein gel chromatographic columns is for filler with TSK G2000 SW xl;

Buffer salt solution: 5mmol/L phosphate buffer [5mmol/L sodium hydrogen phosphate-5mmol/L sodium dihydrogen phosphate (61:39), by 0.1mol/L phosphoric acid adjust ph to 7.0];

Mobile phase: with 5mmol/L mixture of acetonitrile-phosphate buffer=95:5;

Determined wavelength is: 254nm;

Flow velocity: 0.8ml/min;

Column temperature: 25 DEG C;

Sampling volume: 20 μ l.

The advantage that the present invention possesses:

The present invention is the method measuring polymeric impurities in Cephalosporins, compared with existing pharmacopeia data, this method can be applicable to be insoluble to general low boiling point organic solvent or water-fast Cephalosporins, accuracy rate is high, save the step repeatedly investigating method, be applicable to manufacturer for finished product and intermediate monitoring.

Embodiment

Below in conjunction with specific embodiment, the invention will be further described, but do not limit protection scope of the present invention.

The liquid chromatograph that the present invention uses mainly is equipped with UV-detector, uses gel chromatographic columns [TSK G2000SW xl] to be filling agent.

Embodiment: the content of polymkeric substance in external standard method Cefdinir

One: chromatographic condition

Instrument: gel permeation chrommatograph, wherein gel chromatographic columns [TSK G2000SW xl (300mm*7.8)] is filling agent;

Buffer salt solution: 5mmol/L phosphate buffer [5mmol/L sodium hydrogen phosphate-5mmol/L sodium dihydrogen phosphate (61:39), by 0.1mol/L phosphoric acid adjust ph to 7.0];

Mobile phase: 5mmol/L mixture of acetonitrile-phosphate buffer=95:5;

Determined wavelength: 254nm;

Flow velocity: 0.8ml/min;

Column temperature: 25 DEG C.

Two: experimental procedure

1) solution preparation method:

Need testing solution: newly join accurate weighing this product 25mg before use, is placed in the brown measuring bottle of 50ml, after adding above-mentioned 5mol/L phosphate buffer 2.00ml dissolving, is diluted with water to scale, shakes up, as need testing solution.

Reference substance solution: accurate weighing Cefdinir reference substance 25mg, is placed in the brown measuring bottle of 50ml, after adding above-mentioned 5mol/L phosphate buffer 2.00ml dissolving, is diluted with water to scale, shake up, precision measures 1.00ml, in 10ml measuring bottle, be diluted with water to scale, shake up, in contrast product solution.

2) Examination on experimental operation

A) standard curve making:

According to the preparation of the solution of reference substance, obtain the Cefdinir reference substance solution of variable concentrations, shake up, for subsequent use.

Claims (9)

1. one kind measures the method for polymkeric substance in Cephalosporins, it is characterized in that: adopt gel permeation chrommatograph to measure, UV detect wavelength is 254nm, with the chromatographic column that TSK G2000SW xl is new packing, post case temperature 20 ~ 35 DEG C, the mixed solution formed according to a certain ratio with buffer salt solution and organic phase is mobile phase, its flow velocity 0.6 ~ 2.0ml/min.

2. method according to claim 1, is characterized in that, the organic phase in described mobile phase is acetonitrile.

3. method according to claim 1, is characterized in that, described buffer salt solution is phosphate buffer, primarily of sodium hydrogen phosphate and sodium dihydrogen phosphate composition.

4. method according to claim 1, is characterized in that, the concentration of described buffer salt solution is 5mmol/L.

5. method according to claim 1, is characterized in that, in described buffer salt solution, the concentration of disodium phosphate soln is the concentration of 5mmol/L and sodium dihydrogen phosphate is 5mmol/L.

6. method according to claim 1, is characterized in that, in described buffer salt solution, the volume ratio of disodium phosphate soln-sodium dihydrogen phosphate is 20 ~ 80:80 ~ 20, is preferably 60 ~ 70:40 ~ 30.

7. method according to claim 1, is characterized in that, the pH value of described buffer salt solution is 7.0.

8. method according to claim 1, is characterized in that, the volume ratio of described buffer salt solution-organic phase is 95 ~ 50:5 ~ 50.Be preferably 90 ~ 95:10 ~ 5.

9. method according to claim 1, is characterized in that, described method is external standard method, and its concrete steps are as follows:

1) typical curve and the range of linearity: get the known Cefdinir reference substance of content for contrast, gradient dilution, with phosphate buffered solution and acetonitrile for mobile phase, cross chromatographic column, detect under determined wavelength, record chromatogram, obtains the parameter such as peak height and peak area, obtains typical curve and the range of linearity;

2) external standard method Cefdinir polymer content: select suitable concentration in the range of linearity, preparation contrast solution and sample solution, measure under selected chromatographic condition, record chromatogram, calculate with phase optical parameter by external standard method, obtain the content of Cefdinir polymkeric substance.