Hanyu Pinyin

jǔ yuán suān nà

Latin Name

Sodium Citrate

Alias

Trisodium Citrate

Sodium Citrate (Sodium Citrate as it is commonly known contains 2 molecules of water of crystallization)

Chemical Name

Sodium 2-hydroxypropane-1,2,3-tricarboxylic acid

Molecular formula and molecular weight

Chemical symbols. /p>

Sodium 2-hydroxypropane-1,2,3-tricarboxylate

Molecular formula and molecular weight

C6H5O7Na3-2H2O; 294.10 (according to the international atomic weight of 1983)

Structural formula

CH2-COONa

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HO-C-COONa

How much does it contain? /p>

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CH2-COONa

Properties

Colorless or white crystalline particles or crystalline powder, odorless, salty taste, cool, soluble in water, insoluble in ethanol, decomposed overheat, slightly deliquescent in moist air, slightly weathered in hot air. Relative density 1.19, melting point 150 ℃ (this temperature when the loss of water of crystallization), solution pH value of about 8.

Performance

(1) safe and non-toxic performance. As the raw materials for the preparation of sodium citrate are basically derived from food, it is absolutely safe and reliable, and will not be harmful to human health. The Food and Agriculture Organization of the United Nations and the World Health Organization do not impose any restriction on its daily intake, which can be regarded as a non-toxic product.

(2) Biodegradability. Sodium citrate is partially transformed into citric acid when diluted by a large amount of water in nature, and the two ****exist in the same system. Citric acid in water by oxygen, heat, light, and the role of microorganisms, it is easy to biodegradation. Its decomposition pathway is generally through the ursolic acid, itaconic acid, citraconic acid 酑, transformed into carbon dioxide and water.

(3) It has the ability of metal ion complexation. Sodium citrate has good complexing ability for metal ions such as Ca2+ and Mg2+, and also for other metal ions such as Fe2+ and other ions.

(4) Excellent solubility properties in water, and the solubility increases with the rise of water temperature.

(5) Good pH adjustment and buffering properties. Sodium citrate is a weak acid and strong alkali salt, and citric acid can form a strong pH buffer, so in some unsuitable for pH changes in a wide range of occasions has its important use. In addition, sodium citrate also has excellent retardation performance and stability.

Main applications

Widely used in food, beverage, spice industry as acidulants, flavoring agents, preservatives, preservatives, buffers, chelating agents. It is used as antioxidant, plasticizer and detergent in chemical industry, cosmetic industry and washing industry. Anti-coagulant in pharmaceutical industry. Chemical, leather, printing, non-toxic plating and atomic energy industries.

Role and use in medicine

Citrate root and calcium ions in the blood to form a complex that is difficult to dissociate, calcium ions are one of the substances required in the process of coagulation, the reduction of calcium ions in the blood, while the blood coagulation is impeded.

This product is only used for in vitro anticoagulation.

Use: To prevent blood coagulation during blood transfusion, add 10 ml of sodium citrate injection for blood transfusion per 100 ml.

Precautions: When a large number of blood transfusions are made, an appropriate amount of calcium should be injected in order to prevent the hemostatic calcium from being too low.

Main role in cosmetics

Speeding up keratin renewal, commonly used in lotions, creams, shampoos, whitening products, anti-aging products,

acne products and so on. The renewal of keratin helps to peel off the melanin in the skin, to thin the pores, and to dissolve the blackheads.

Drug Analysis

Method Name:

Sodium Citrate Determination-Neutralization Titration Method

Application Scope:

Substance is placed in a conical flask, add glacial acetic acid and shake to dissolve it, add acetic anhydride and crystal violet indicator solution, and titrate the solution with perchloric acid titrant (0.1 mol/L) until the solution shows a blue-green color. Read out the amount of perchloric acid titrant used and calculate the content of sodium citrate.

Principle of the method:

Place the test material in a conical flask, add glacial acetic acid and shake to dissolve, add acetic anhydride and crystal violet indicator solution, titrate with perchloric acid titrant (0.1mol/L) until the solution shows blue-green color. Read the amount of perchloric acid titrant used and calculate the content of sodium citrate.

Reagents:

1. water (freshly boiled and placed at room temperature)

2. perchloric acid titrant (0.1mol/L)

3. crystalline violet indicator solution

4. anhydrous glacial acetic acid

5. acetic anhydride

3.6 Benchmark Potassium Hydrogen Phthalate

Instruments:

Instruments:

Sample preparation:

1. Perchloric acid titrant (0.1mol/L)

Formulation: take anhydrous glacial acetic acid (according to the water content, every 1g of water plus acetic anhydride 5.22mL) 750mL, add perchloric acid (70%-72%) 8.5mL, shake it well, and then slowly add acetic anhydride 23mL dropwise at room temperature, shaking it as it is being added and shaking it well after it has been added, and then put it into the cold. Add anhydrous glacial acetic acid to make 1000mL, shake well and leave for 24 hours. If the test product is easily acetylated, the water content of this page should be measured by water content measurement method, and then adjusted with water and acetic anhydride to the water content of this solution is 0.01% -0.2%.

Calibration: take about 0.16g of the benchmark potassium hydrogen phthalate dried to constant weight at 105℃, weigh it precisely, add 20mL of anhydrous glacial acetic acid to make it dissolve, add 1 drop of crystal violet indicator solution, titrate the solution slowly to blue, and correct the result of titration with a blank test. Each 1mL of perchloric acid titrant (0.1mol/L) is equivalent to 20.42mg of potassium hydrogen phthalate. The concentration of this solution can be calculated according to the consumption of this solution and the amount of potassium hydrogen phthalate taken.

Storage: in a brown glass bottle, tightly closed.

2. Crystalline violet indicator solution

Take 0.5g of crystalline violet, add 100mL of glacial acetic acid to make it dissolve, it is obtained.

Procedure:

Weigh about 80mg of the test material, put it in a conical flask, add 5mL of glacial acetic acid to heat and dissolve it, let it cool down, add 10mL of acetic anhydride and 1 drop of crystal violet indicator solution, titrate the solution with perchloric acid titrant (0.1 mol/L) until the solution shows blue-green color, and correct the titration result with a blank test. Record the volume of perchloric acid titrant consumed (mL), each 1mL of perchloric acid titrant (0.1mol/L) is equivalent to 8.602mg of C6H5Na3O7.

Note 1: "Precision weighing" means that the weight taken should be accurate to one-thousandth of the weight weighed. "Precision measurement" means that the accuracy of the volume measured should be in accordance with the precision requirements of the national standard for that volume of pipette.

References:

Chinese Pharmacopoeia of the People's Republic of China, compiled by the State Pharmacopoeia Committee, Chemical Industry Press, 2005 edition, Part II, p.382.

Chinese Pharmacopoeia of the 2010 edition of the revision of the additions to the content

Sodium Citrate

Juyuansuanna

Sodium Citrate

[Revised]

Identification The aqueous solution of this product shows the flame reaction of the sodium salt with the identification of citrate counter