Chloroquine Hydrochloride Injection
C18H26ClN3·2HCl 392.79

1,4-Pentanediamine,N4-(7-chloro-4-quinolinyl)-N1,N1-diethyl-,dihydrochloride.
7-(Chloro-4-4-diethylamino)-1-methylbutylaminoquinoline dihydrochloride [3545-67-3].
»Chloroquine Hydrochloride Injection is a sterile solution of Chloroquine in Water for Injection prepared with the aid of Hydrochloric Acid.It contains,in each mL,not less than 47.5mg and not more than 52.5mg of C18H26ClN3·2HCl.
Packaging and storage— Preserve in single-dose containers,preferably of Type Iglass.
Identification—
A: The UVabsorption spectrum of the solution employed for measurement of absorbance in the Assayexhibits maxima and minima at the same wavelengths as that of a similar solution of USP Chloroquine Phosphate RS,concomitantly measured.The ratio A343/A329is between 1.00and 1.15.
B: To 20mLof a dilution of Injection with water,containing about 20mg of chloroquine hydrochloride,add 5mLof trinitrophenol TS:a yellow precipitate is formed.Filter,wash the precipitate with water until the last washing is colorless,and dry over silica gel:the precipitate melts between 205and 210.[Caution—Picrates may explode.]
C: It responds to the tests for Chloride á191ñ.
Bacterial endotoxins á85ñ— It contains not more than 0.7USP Endotoxin Unit per mg of chloroquine hydrochloride.
pHá791ñ: between 5.5and 6.5.
Other requirements— It meets the requirements under Injections á1ñ.
Assay— Transfer an accurately measured volume of Injection,equivalent to about 150mg of chloroquine hydrochloride,to a 1000-mLvolumetric flask,and dilute with water to volume.Transfer 5.0mLof this solution to a 100-mLvolumetric flask,add 10mLof dilute hydrochloric acid (1in 100),and dilute with water to volume.Dissolve an accurately weighed quantity of USP Chloroquine Phosphate RSin dilute hydrochloric acid (1in 1000),and dilute quantitatively and stepwise with dilute hydrochloric acid (1in 1000)to obtain a Standard solution having a known concentration of about 10µg per mL.Concomitantly determine the absorbances of both solutions at the wavelength of maximum absorbance at about 343nm,with a suitable spectrophotometer,using water as the blank.Calculate the quantity,in mg,of C18H26ClN3·2HCl in the portion of Injection taken by the formula:
15.23C(AU/AS),
in which Cis the concentration,in µg per mL,of USP Chloroquine Phosphate RSin the Standard solution,and AUand ASare the absorbances of the solution from the Injection and the Standard solution,respectively.
Auxiliary Information— Staff Liaison:Behnam Davani,Ph.D.,MBA,Senior Scientist
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 444
Phone Number:1-301-816-8394