Diphenhydramine Hydrochloride CAS:147-24-0

1. General situation :

1. Product name and code: Product name: Diphenhydramine hydrochloride        

2. Molecular formula: Molecular formula: C ₁₇ H ₂₁ NO·HCl Molecular weight: 291.82

3. Structural formula: 

2. Characters :

1. This product is white crystalline powder; odorless.

2. This product is very soluble in water, soluble in ethanol or chloroform, slightly soluble in acetone, and very slightly soluble in ether.

3. Melting point: melting point of the this product (General Rule 0612) is 167～171℃.

3. identification:

1. Take about 5mg of this product, add 1 drop of sulfuric acid, it will appear yellow at first, and then it will become orange-red; add water dropwise, and it will become a white emulsion.

2. Take this product, add 0.01mol/L hydrochloric acid solution to dissolve and dilute to make a solution containing about 0.5mg per 1ml, measured by ultraviolet-visible spectrophotometry (general rule 0401), the maximum is at the wavelengths of 253nm and 258nm absorb.

3. The infrared absorption spectrum of this product should be consistent with the control spectrum (spectrum set 365).

4. The aqueous solution of this product shows the identification reaction of chloride (1) (General Principle 0301).

4. check:

1. The clarity and color of the solution: Take 1.0g of this product, add 20ml of freshly boiled cold water to dissolve, the solution should be clear and colorless; if it develops, compare it with the yellow standard colorimetric solution No. 1 (General Rule 0901 First Method) , No deeper.

2. Related substances: Take this product, add mobile phase to dissolve and dilute to make a solution containing about 2.5mg per 1ml, as the test solution; accurately measure 1ml, put it in a 100ml measuring flask, and dilute to the mark with mobile phase , Shake well, as a control solution. According to the chromatographic conditions under the content determination item, accurately measure 20μl each of the control solution and the test solution , and inject them into the liquid chromatograph respectively, and record the chromatogram until the retention time of the main component peak is 3 times. If there are impurity peaks in the chromatogram of the test solution, the area of ​​a single impurity peak shall not be greater than 0.5 times (0.5%) of the main peak area of ​​the control solution, and the sum of the impurity peak areas shall not be greater than the main peak area of ​​the control solution (1.0%).

3. Loss on drying: Take this product and dry it to constant weight at 105°C. The weight loss should not exceed 0.5% (General Rule 0803).

4. Residue on ignition: no more than 0.1% (general rule 0841).

5. Microbial limit inspection: In accordance with the law (General Rule 1105 and General Rule 1106), the total number of aerobic bacteria in each 1g of the test product must not exceed 2000cfu, the number of molds and yeasts must not exceed 200cfu, and no Escherichia coli can be detected.

5. Assay Determine :

according to high performance liquid chromatography ( General Principle 0512).

1, chromatographic conditions and system suitability test  with cyano bonded silica as filler; acetonitrile - water - triethylamine (50:50: 0.5) (adjusted with glacial acetic acid to pH 6.5) as the mobile phase; detection wavelength It is 258nm. Take benzophenone 5mg of , put it in a 100ml measuring flask, add 5ml of acetonitrile to dissolve it, dilute to the mark with water, and shake well; take another 5mg of diphenhydramine hydrochloride and place it in a 10ml measuring flask, add 1ml of the above benzophenone solution, and water Dilute to the mark, shake well, take 20μl into the liquid chromatograph, and record the chromatogram. The number of theoretical plates should not be less than 5000 calculated based on the peak of diphenhydramine hydrochloride, and the resolution of the peak of diphenhydramine hydrochloride and benzophenone should be greater than 2.0.

2. Determination method: Take this product, accurately weigh it, add water to dissolve and quantitatively dilute to make per 1ml containing about 0.5mg a solution , accurately measure 20μl into the liquid chromatograph, record the chromatogram; take diphenhydral hydrochloride separately The reference substance should be measured in the same way. Calculate the peak area according to the external standard method to obtain.

Calculated as dry product, the content of C ₁₇ H ₂₁ NO·HCl should be 98.0%-102%.

6. Inspection items and limits:

7. Sampling regulations:

see SOP.QC-QY-004 "Standard Operating Procedures for Sampling of Finished Products".

8. Inspection method :

see SOP.QC-CJ-040 " Diphenhydramine Hydrochloride Standard Operating Procedures for Inspection of Finished Products ".

9. Packaging form :

25g/barrel, the inner packaging is a medicinal low-density polyethylene bag, the outer packaging is a medicinal high-density polyethylene bag, and the outer packaging is a cardboard drum.

10. Storage conditions and precautions :

sealed and stored.

11. Validity period: 48 months.