Pyridoxine Hydrochloride Injection
»Pyridoxine Hydrochloride Injection is a sterile solution of Pyridoxine Hydrochloride in Water for Injection.It contains not less than 95.0percent and not more than 115.0percent of the labeled amount of Pyridoxine Hydrochloride (C8H11NO3·HCl).
Packaging and storage— Preserve in single-dose or in multiple-dose containers,preferably of Type Iglass,protected from light.
Identification— Evaporate a volume of Injection,equivalent to about 50mg of pyridoxine hydrochloride,on a steam bath to dryness.Add 5mLof dehydrated alcohol,and again evaporate to dryness.Dry the residue at 105for 3hours:the residue so obtained responds to Identificationtests Aand Bunder Pyridoxine Hydrochloride.
Bacterial endotoxins á85ñ— It contains not more than 0.4USP Endotoxin Unit per mg of pyridoxine hydrochloride.
pHá791ñ: between 2.0and 3.8.
Other requirements— It meets the requirements under Injections á1ñ.
Change to read:
Assay—
Ammonium chloride–ammonium hydroxide buffer— Dissolve 16g of ammonium chloride in 70mLof water,add 16mLof ammonium hydroxide,dilute with water to 100mL,mix,and filter.
Chlorimide solution— Dissolve 40mg of 2,6-dichloroquinone-chlorimide in 100mLof isopropyl alcohol.Store the solution in a refrigerator,and use within one month.Do not use the solution if it has become pink.
Standard stock solution— Dissolve a suitable quantity of USP Pyridoxine Hydrochloride RS,accurately weighed,in 0.1Nhydrochloric acid,quantitatively dilute with the same solvent to obtain a solution having a known concentration of about 0.1mg per mL,and mix.Keep the solution in an amber bottle,in a cool place.
Standard preparation— In a 100-mLvolumetric flask dilute 10.0mLof Standard stock solutionwith water to volume,and mix.Prepare this solution daily as needed.
Assay preparation— Dilute an accurately measured volume of Injection,equivalent to about 100mg of pyridoxine hydrochloride,quantitatively and stepwise with water to a concentration of about 10µg of pyridoxine hydrochloride per mL.
Procedure—
(a)Pipet 5mLof the clear Assay preparationinto a flask,add 25.0mLof isopropyl alcohol,and mix.Pipet 5mLof the isopropyl alcohol dilution into a glass-stoppered,25-mLgraduated cylinder or test tube,and add in succession,mixing after each addition,1.0mLof Ammonium chloride–ammonium hydroxide buffer,1.0mLof sodium acetate solution (1in 5),and 1.0mLof water.Cool to about 25,then add 1.0mLof Chlorimide solution,shake vigorously for 10seconds,accurately timed.Sixty seconds,accurately timed,after the addition of the Chlorimide solution,determine the absorbance at the wavelength of maximum absorbance at about 650nm,with a suitable spectrophotometer,using water as the blank.[NOTE—Make the reading promptly to avoid errors due to fading of the color.]Designate the absorbance as AU.
(b)Repeat procedure(a),but substitute 1.0mLof boric acid solution (1in 20)for the 1.0mLof water.Designate the absorbance as AU¢.
(c)Repeat procedure(a),but substitute 5.0mLof the Standard preparationfor the 5.0mLof the Assay preparation.Designate the absorbance as AS.
(d)Repeat procedure(c),but substitute 1.0mLof boric acid solution (1in 20)for the 1.0mLof water.Designate the absorbance as AS¢.
Calculate the quantity,in mg,of Pyridoxine Hydrochloride (C8H11NO3·HCl)in each mLof the Injection taken by the formula:
10(C/V)(AU-AU¢)/(AS-AS¢),USP28
in which Cis the concentration,in µg per mL,of USP Pyridoxine Hydrochloride RSin the Standard preparation;Vis the volume,in mL,of Injection taken;and the other terms are as defined above.USP28
Auxiliary Information— Staff Liaison:Lawrence Evans,III,Ph.D.,Scientist
Expert Committee:(DSN)Dietary Supplements:Non-Botanicals
USP28–NF23Page 1684
Pharmacopeial Forum:Volume No.30(2)Page 583
Phone Number:1-301-816-8389