CN113514604A - Method for measuring total chlorine content in sodium citrate-containing compound preparation - Google Patents
Method for measuring total chlorine content in sodium citrate-containing compound preparation Download PDFInfo
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Abstract
The invention discloses a method for measuring the total chlorine content in a sodium citrate-containing compound preparation, which comprises the following steps: the method comprises the following steps: precisely measuring 10ml of the product, adding 0-3ml of 0.1mol/L calcium nitrate solution, and adding 0-0.3ml of dilute nitric acid; step two: then adding 5ml of 2% dextrin solution and 8 drops of dichloro-fluoro-yellow indicator solution; step three: titrating with silver nitrate titration solution (0.1 mol/L); as a preferable technical scheme of the invention, each 1ml of silver nitrate titration solution (0.1mol/L) is equivalent to 3.545mg of chlorine; the invention has the beneficial effects that: precisely measuring 10ml of the product, adding 5ml of 2% dextrin solution and 8 drops of dichlorofluorescein indicator solution, titrating with silver nitrate titration solution (0.1mol/L), and adding 1ml of 0.1mol/L calcium nitrate solution and 0.1ml of dilute nitric acid on the basis that each 1ml of silver nitrate titration solution (0.1mol/L) is equivalent to 3.545mg of chlorine ], so that the influence of sodium citrate in a sodium citrate-containing compound preparation on the determination of the total chlorine content can be eliminated, and the accuracy of the determination of the total chlorine content is ensured.
Description
Technical Field
The invention belongs to the technical field of medicines, and particularly relates to a method for measuring the total chlorine content in a sodium citrate-containing compound preparation.
Background
The balanced salt solution (for perfusion) is a typical compound preparation containing sodium citrate, and is colorless clear liquid prepared by 0.64 percent of sodium chloride, 0.075 percent of potassium chloride, 0.048 percent of calcium chloride dihydrate, 0.03 percent of magnesium chloride hexahydrate, 0.39 percent of sodium acetate trihydrate and 0.17 percent of sodium citrate dihydrate; the clinical application is mainly used for intraocular or extraocular perfusion liquid and endoscopic washing liquid in ophthalmic surgery and washing liquid of various bone joint cavities, and can also be used for allowing various surgical washing, lavage and cleaning using electrolyte solution, washing, rinsing or soaking of various body cavities, tissues, wounds, drainage tubes and the like which need to be sterilized, and washing, rinsing or soaking of surgical dressings, tools and experimental samples, and can also be used as carriers of pharmaceutical preparations.
At present, a silver nitrate titration method is adopted in the field of medicine for measuring the total chlorine content, and the method specifically comprises the following steps:
precisely measuring 10ml of the product, adding 5ml of 2% dextrin solution and 8 drops of dichlorofluorescein indicator solution, and titrating with silver nitrate titration solution (0.1mol/L), wherein each 1ml of silver nitrate titration solution (0.1mol/L) is equivalent to 3.545mg of chlorine;
however, the balanced salt solution (for perfusion) contains sodium citrate, and the sodium citrate and the silver nitrate can generate oxidation-reduction reaction to generate nano silver insoluble in water, which can interfere the determination of the total chlorine content and influence the judgment of the titration end point.
In order to eliminate the influence of sodium citrate in a sodium citrate-containing compound preparation on the determination of the total chlorine content and ensure the accuracy of the determination of the total chlorine content, a method for determining the total chlorine content in the sodium citrate-containing compound preparation is provided.
Disclosure of Invention
The invention aims to provide a method for measuring the total chlorine content in a sodium citrate-containing compound preparation, so as to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme: a method for measuring the total chlorine content in a sodium citrate-containing compound preparation comprises the following steps:
the method comprises the following steps: precisely measuring 10ml of the product, adding 0-3ml of 0.1mol/L calcium nitrate solution, and adding 0-0.3ml of dilute nitric acid;
step two: then adding 5ml of 2% dextrin solution and 8 drops of dichloro-fluoro-yellow indicator solution;
step three: titration was carried out with silver nitrate titration solution (0.1 mol/L).
As a preferable embodiment of the present invention, the amount of chlorine is 3.545mg per 1ml of silver nitrate titration solution (0.1 mol/L).
As a preferred technical solution of the present invention, the preparation method of the calcium nitrate solution is as follows:
the method comprises the following steps: placing quicklime in a reaction kettle, and uniformly spraying dilute nitric acid on the surface of the quicklime to generate a calcium nitrate solution;
step two: uniformly introducing compressed air into the calcium nitrate solution in the reaction kettle, and adjusting the pH value;
step three: after precipitation, filtration is carried out.
In the second step, compressed air is uniformly introduced into the calcium nitrate solution in the reaction kettle, so that the content of nitrogen oxides in the discharged tail gas is less than or equal to 180 ppm; the pressure in the reaction kettle is 0.3-0.8 MPa.
In a preferred embodiment of the present invention, in the second step, the ph value is adjusted to 7.
In the third step, the precipitation is carried out for 4 to 6 hours and then the filtration is carried out.
In a preferred embodiment of the present invention, the dextrin solution is prepared from distilled water and dextrin.
Compared with the prior art, the invention has the beneficial effects that:
precisely measuring 10ml of the product, adding 5ml of 2% dextrin solution and 8 drops of dichlorofluorescein indicator solution, titrating with silver nitrate titration solution (0.1mol/L), and adding 1ml of 0.1mol/L calcium nitrate solution and 0.1ml of dilute nitric acid on the basis that each 1ml of silver nitrate titration solution (0.1mol/L) is equivalent to 3.545mg of chlorine ], so that the influence of sodium citrate in a sodium citrate-containing compound preparation on the determination of the total chlorine content can be eliminated, and the accuracy of the determination of the total chlorine content is ensured.
Drawings
FIG. 1 is a flow chart of the present invention;
FIG. 2 is a linear relationship diagram of the total chlorine content measurement of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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.
Referring to fig. 1 and fig. 2, the present invention provides a technical solution: a method for measuring the total chlorine content in a sodium citrate-containing compound preparation comprises the following steps:
the method comprises the following steps: precisely measuring 10ml of the product, adding 1ml of 0.1mol/L calcium nitrate solution, and adding 0.1ml of dilute nitric acid;
step two: then adding 5ml of 2% dextrin solution and 8 drops of dichloro-fluoro-yellow indicator solution;
step three: titration was carried out with silver nitrate titration solution (0.1 mol/L).
Each 1ml of silver nitrate titration solution (0.1mol/L) corresponds to 3.545mg of chlorine.
Calculating the formula:
in the formula: 4.5754 is the labeled amount of total chlorine, mg/ml;
c is the calibration concentration of silver nitrate titration solution (0.1mol/L), mol/L;
v is the volume of consumed silver nitrate titration solution (0.1mol/L), ml.
In this embodiment, the preparation method of the calcium nitrate solution is preferably as follows:
the method comprises the following steps: placing quicklime in a reaction kettle, and uniformly spraying dilute nitric acid on the surface of the quicklime to generate a calcium nitrate solution;
step two: uniformly introducing compressed air into a calcium nitrate solution in a reaction kettle, so that the content of nitrogen oxides in the discharged tail gas is less than or equal to 180ppm, the pressure in the reaction kettle is 0.3-0.8MPa, and the pH value is adjusted to be 7;
step three: precipitating for 4-6h, and filtering.
In this embodiment, the dextrin solution is preferably prepared from distilled water and dextrin.
The effect of adding different amounts of 0.1mol/L calcium nitrate solution on the determination of the total chlorine content was investigated:
respectively and precisely measuring 10ml of blank auxiliary materials and 10ml of samples, respectively adding 0.1mol/L calcium nitrate solution with different amount, then adding 5ml of 2% dextrin solution and 8 drops of dichlorofluorescein indicator solution, titrating with silver nitrate titrating solution (0.1mol/L), observing and recording experimental phenomena, and obtaining the results shown in the table 1:
TABLE 1 results of the study of the addition of various amounts of 0.1mol/L calcium nitrate solution
And (4) conclusion: according to the results, the calcium nitrate solution with different amounts of 0.1mol/L is added, and the blank auxiliary materials and the solution before the titration of the sample have the same color; when 0-0.5ml of 0.1mol/L calcium nitrate solution is added, the solution titrated by the blank auxiliary materials is light yellow with the generation of precipitates, and the solution titrated by the sample is light pink; when 1-3ml of 0.1mol/L calcium nitrate solution is added, the solution titrated by blank auxiliary materials is light yellow but no precipitate is generated, and the solution titrated by the sample is light pink, so that 10ml of the sample is added with 1ml of 0.1mol/L calcium nitrate solution to be used as a test sample for titration.
The effect of different acidity on the titration endpoint was studied:
precisely measuring 10ml of a sample, adding 1ml of 0.1mol/L calcium nitrate solution, respectively adding different amounts of dilute nitric acid, then adding 5ml of 2% dextrin solution and 8 drops of dichlorofluorescein indicator solution, titrating with silver nitrate titrating solution (0.1mol/L), observing and recording experimental phenomena, wherein the results are shown in Table 2:
TABLE 2 results of the study with different amounts of dilute nitric acid
And (4) conclusion: from the above results, it can be seen that the titration end point color is light pink when 0-0.05ml of dilute nitric acid is added; when 0.1-0.3ml of dilute nitric acid is added, the color of the titration end point is pink, so 0.1ml of dilute nitric acid is selected to be added into a test sample.
In summary, it was determined that the addition of 1ml of 0.1mol/L calcium nitrate solution and 0.1ml of dilute nitric acid can eliminate the effect of sodium citrate in the sodium citrate-containing compound preparation on the determination of total chlorine content.
Precisely measuring 10ml of the product, adding 5ml of 2% dextrin solution and 8 drops of dichlorofluorescein indicator solution, titrating with silver nitrate titration solution (0.1mol/L), adding 1ml of 0.1mol/L calcium nitrate solution on the basis that each 1ml of silver nitrate titration solution (0.1mol/L) is equivalent to 3.545mg of chlorine, and combining citrate ions with calcium ions to form a soluble complex which is not easy to dissociate, thereby eliminating the influence of sodium citrate on the total chlorine content; precisely measuring 10ml of the product, adding 5ml of 2% dextrin solution and 8 drops of dichlorofluorescein indicating solution, titrating with silver nitrate titration solution (0.1mol/L), and adding 0.1ml of dilute nitric acid on the basis that each 1ml of silver nitrate titration solution (0.1mol/L) is equivalent to 3.545mg of chlorine, so that the end point can be accurately and obviously indicated.
The methodology of the method of this embodiment was validated:
(1) specificity
Control solution: precisely weighing 754.2mg of sodium chloride purity standard substance dried at 110 ℃ to constant weight, placing in a 100ml measuring flask, diluting with water to scale, and shaking;
the water, the blank auxiliary materials, the reference substance solution and the test sample are respectively measured according to the optimized method, and the results are shown in the following table:
specificity result table
And (4) conclusion: tests prove that the test phenomena of the test sample and the reference sample are consistent, and the blank auxiliary materials do not interfere the content determination of the total chlorine, which indicates that the method has good specificity.
(2) Precision degree
Taking a same batch of balanced salt solution (for perfusion), preparing 6 parts of laboratory technician A and laboratory technician B in parallel at the same time, measuring according to an optimized method, calculating the content of total chlorine, and obtaining the results shown in the following table:
table of precision results
And (4) conclusion: through tests, the RSD of the content measurement results of different persons for 12 times is less than 2.0 percent, which shows that the method has good precision.
(3) Accuracy of
The test for the recovery rate of the product is designed by adopting a sample standard adding method, adding 80%, 100% and 120% of the marked concentration of the total chlorine content to carry out an experiment, and calculating the recovery rate of the total chlorine;
test solution: precisely measuring 10ml of balanced salt solution (for perfusion), placing the balanced salt solution in a 250ml conical flask, adding 80ml of water and 0.1ml of dilute nitric acid, adding 5ml of 2% dextrin solution and 8 drops of dichlorofluorescein indicator solution, and uniformly mixing to obtain (2 parts in parallel);
80% accuracy solution: respectively and precisely weighing 61.6mg, 61.2mg and 62.6mg of sodium chloride purity standard substances dried to constant weight at 110 ℃, respectively placing the sodium chloride purity standard substances into 250ml conical flasks, respectively and precisely adding 10ml of balanced salt solution (for perfusion), 80ml of water and 0.1ml of dilute nitric acid, adding 5ml of 2% dextrin solution and 8 drops of dichlorofluorescein indicator solution, and uniformly mixing to obtain the sodium chloride purity standard substance;
100% accuracy solution: respectively and precisely weighing 76.2mg, 76.6mg and 75.4mg of sodium chloride purity standard substances dried to constant weight at 110 ℃, respectively placing the sodium chloride purity standard substances into 250ml conical flasks, respectively and precisely adding 10ml of balanced salt solution (for perfusion), 80ml of water and 0.1ml of dilute nitric acid, adding 5ml of 2% dextrin solution and 8 drops of dichlorofluorescein indicator solution, and uniformly mixing to obtain the sodium chloride purity standard substance;
120% accuracy solution: respectively and precisely weighing 92.0mg, 93.7mg and 91.4mg of sodium chloride purity standard substances dried to constant weight at 110 ℃, respectively placing the sodium chloride purity standard substances into 250ml conical flasks, respectively and precisely adding 10ml of balanced salt solution (for perfusion), 80ml of water and 0.1ml of dilute nitric acid, adding 5ml of 2% dextrin solution and 8 drops of dichlorofluorescein indicator solution, and uniformly mixing to obtain the sodium chloride purity standard substance;
the solutions were titrated with silver nitrate titrating solutions, and the results are shown in the following table:
accuracy result table
And (4) conclusion: tests show that the average recovery rate is 99.8%, and the RSD is 0.94%, which indicates that the method has good accuracy.
(4) Linear range
Linear control stock solutions: precisely weighing 7.54g of standard sodium chloride dried at 110 ℃ to constant weight, placing the sodium chloride in a 100ml measuring flask, diluting the sodium chloride to a scale with water, and shaking up;
linear solution: precisely measuring 5ml, 8ml, 9ml, 10ml, 11ml and 12ml of linear reference substance stock solution, respectively placing in a 100ml measuring flask, diluting with water to scale, shaking up, and respectively using as 50%, 80%, 90%, 100%, 110% and 120% linear solutions;
taking each linear solution, determining according to an optimized method, taking the concentration (C) as an abscissa (X axis) and the volume (V) of the consumed silver nitrate titration solution as an ordinate (Y axis), and performing linear regression analysis, wherein the results are shown in the following table:
linear range results table
And (4) conclusion: the total chlorine is in the concentration range of 2.287-5.489mg/ml, and the volume of consumed silver nitrate titration solution has a good linear relation with the concentration.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (7)
1. A method for measuring the total chlorine content in a sodium citrate-containing compound preparation is characterized by comprising the following steps: the measurement method comprises the following steps:
the method comprises the following steps: precisely measuring 10ml of the product, adding 0-3ml of 0.1mol/L calcium nitrate solution, and adding 0-0.3ml of dilute nitric acid;
step two: then adding 5ml of 2% dextrin solution and 8 drops of dichloro-fluoro-yellow indicator solution;
step three: titration was carried out with silver nitrate titration solution (0.1 mol/L).
2. The method for determining the total chlorine content in the sodium citrate-containing compound preparation according to claim 1, which is characterized in that: each 1ml of silver nitrate titration solution (0.1mol/L) corresponds to 3.545mg of chlorine.
3. The method for determining the total chlorine content in the sodium citrate-containing compound preparation according to claim 1, which is characterized in that: the preparation method of the calcium nitrate solution comprises the following steps:
the method comprises the following steps: placing quicklime in a reaction kettle, and uniformly spraying dilute nitric acid on the surface of the quicklime to generate a calcium nitrate solution;
step two: uniformly introducing compressed air into the calcium nitrate solution in the reaction kettle, and adjusting the pH value;
step three: after precipitation, filtration is carried out.
4. The method for determining the total chlorine content in the sodium citrate-containing compound preparation according to claim 3, which is characterized in that: in the second step, compressed air is uniformly introduced into the calcium nitrate solution in the reaction kettle, so that the content of nitrogen oxides in the discharged tail gas is less than or equal to 180 ppm; the pressure in the reaction kettle is 0.3-0.8 MPa.
5. The method for determining the total chlorine content in the sodium citrate-containing compound preparation according to claim 3, which is characterized in that: in the second step, the ph value is adjusted to be 7.
6. The method for determining the total chlorine content in the sodium citrate-containing compound preparation according to claim 3, which is characterized in that: in the third step, the precipitate is filtered after 4 to 6 hours.
7. The method for determining the total chlorine content in the sodium citrate-containing compound preparation according to claim 1, which is characterized in that: the dextrin solution is prepared from distilled water and dextrin.
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| CN103149306A (en) * | 2013-03-28 | 2013-06-12 | 中粮生物化学（安徽）股份有限公司 | Method of analyzing content of anions in citric acid-containing solution |
| JP2016151549A (en) * | 2015-02-19 | 2016-08-22 | ラボテック株式会社 | Method for analyzing concentration of sodium chloride, sodium chloride concentration analyzer, and sodium hypochlorite analyzer |
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2021
- 2021-08-30 CN CN202111005281.6A patent/CN113514604A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1465080A (en) * | 1973-04-16 | 1977-02-23 | Miles Lab | Method and test kit for estimating chemical pollution in aqueous fluids |
| CN103149306A (en) * | 2013-03-28 | 2013-06-12 | 中粮生物化学（安徽）股份有限公司 | Method of analyzing content of anions in citric acid-containing solution |
| JP2016151549A (en) * | 2015-02-19 | 2016-08-22 | ラボテック株式会社 | Method for analyzing concentration of sodium chloride, sodium chloride concentration analyzer, and sodium hypochlorite analyzer |
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