What are the special impurities commonly found in aspirin medications?

The impurities are free salicylic acid;

The cause is the incomplete reaction of acetic anhydride and salicylic acid during the synthesis of acetylsalicylic acid and the hydrolysis introduction during the preparation process;

The main examination principle is that the phenolic hydroxyl group of salicylic acid reacts with iron salt to form violet color, and the color comparison should not be deeper;

Method: take an appropriate amount of fine powder of this product (equivalent to aspirin, add 3ml of anhydrous chloroform, stir continuously for 2 minutes, filter with anhydrous chloroform-moistened filter paper, wash the filter residue with anhydrous chloroform for 2 times, 1ml each time, combine the filtrate and lotion, and ventilate at room temperature until dry; After the residue is dissolved with 4ml of absolute ethanol, it is transferred to a 100ml measuring flask, the container is washed with a small amount of 5 ethanol, the washing solution is incorporated into the measuring flask, 5 ethanol is added to dilute to the scale, shake well, 50ml is divided, and a new dilute ammonium iron sulfate solution is added immediately Take 1ml of hydrochloric acid solution (9 100), add 2ml of ammonium iron sulfate indicator solution, add an appropriate amount of water to make 100ml 1ml, shake well, develop color within 30 seconds, and the control solution (precision weighing salicylic acid, put it in a 1000ml measuring flask, add water to dissolve, Add 1ml of glacial acetic acid, shake well, then add an appropriate amount of water to the scale, shake well, take a precise measure, add 2ml of absolute ethanol and 5 ethanol to make 50ml, plus the newly prepared dilute sulfuric acid.

1ml of ammonium iron solution, shake well) and not deeper (

Hehe, it's easier to use high-performance liquid phase.

The impurity that can easily cause allergic reactions is acetylsalicylic anhydride ......

Impurities:] Free salicylic acid.

Causes] Synthesis of acetylsalicylic acid.

When the reaction of acetic anhydride and salicylic acid is incomplete, and the hydrolysis is introduced during the preparation; The main examination principle is that the phenolic hydroxyl group of salicylic acid reacts with iron salt to form violet color, and the color comparison should not be deeper;

Removal method:].

Take an appropriate amount of fine powder of this product (equivalent to aspirin.

Add anhydrous chloroform.

3 ml, stirring constantly2

minutes, filter with anhydrous chloroform-moistened filter paper, wash the filter residue with anhydrous chloroform twice, 1ml each time, combine the filtrate and lotion, and ventilate at room temperature until dry; Absolute ethanol for residues.

After 4ml is dissolved, transfer 100ml

Measuring flask, use a small amount of 5

Ethanol wash containers, lotions are incorporated into measuring flasks, add.

5 Ethanol is diluted to the scale, shake well, divide 50ml, and add new dilute ammonium iron sulfate immediately.

Solution take 1ml of hydrochloric acid solution (9 100) and add 2ml of ammonium iron sulfate indicator solution

After that, add an appropriate amount of water to make 100ml

Shake 1ml well, develop color within 30 seconds, and control solution (precision weigh salicylic acid, put it in a 1000ml measuring flask, add water to dissolve, add glacial acetic acid.

1ml, shake well, then add an appropriate amount of water to the scale, shake well, take a precise measure, add 2ml of absolute ethanol and 5 ethanol to make 50ml, plus 1ml of the newly prepared dilute ammonium iron sulfate solution, shake well) compared, not deeper (

This effectively removes impurities.

Summary. Hello, I will solve your doubts for you below, I hope it can help you.

The impurities are free salicylic acid; The cause is the incomplete reaction of acetic anhydride and salicylic acid during the synthesis of acetylsalicylic acid and the hydrolysis introduction during the preparation process; The main examination principle is that the phenolic hydroxyl group of salicylic acid reacts with iron salt to form violet color, and the color comparison should not be deeper;

I really hope I can help you, and I wish you happiness every day!

What are the general impurities in the aspirin pharmacopoeia.

Hello, I will solve your doubts for you below, and I hope to help the lead ship to you. The impurities are free salicylic acid; The cause is the incomplete reaction of acetic anhydride and salicylic acid during the synthesis of acetylsalicylic acid and the hydrolysis introduction during the preparation process; The main inspection principle is the effect of salicylic acid phenolic hydroxyl group and iron iron salt to produce violet color, and the color comparison can not be deeper, I sincerely hope that my can help you, Huai Pai Liang, I wish you a happy day!

What about special impurities.

It's salicylic acid.

1) The special impurity in aspirin is salicylic acid.

2) The principle of the inspection is to use the aspirin structure without phenolic hydroxyl group, can not interact with Fe3+, and salicylic acid can be combined with Fe3+ to form violet, and the color and luster generated by a sharp quantitative salicylic acid control solution are compared with the reincarnation to control the content of free salicylic acid.

Answer]: ABCDE

The impurities of aspirin and its **, most of the rock leakage impurities are mainly due to incomplete acetylation in the production process or partial hydrolysis during storage.

It is because acetylsalicylic acid is easily hydrolyzed.

When taking small doses (less than 1 g) of acetylsalicylic acid orally, its metabolism is carried out according to first-order kinetics with a half-life of about 2 to 3 hours. When the dosage is 1g, its metabolic mode changes to zero-order kinetics, and the half-life is extended to 15 to 30 hours, if the dose is increased again, salicylic acid poisoning can occur. Therefore, when a large number of rheumatoid and rheumatoid arthritis are used for a long time, it is best to monitor the blood drug concentration to determine the dose and interval of administration.