Dopamine Hydrochloride Injection
» Dopamine Hydrochloride Injection is a sterile solution of Dopamine Hydrochloride in Water for Injection. It contains not less than 95.0 percent and not more than 105.0 percent of the labeled amount of C8H11NO2·HCl. It may contain a suitable antioxidant.
[noteDo not use the Injection if it is darker than slightly yellow or discolored in any other way. ]
Packaging and storage
Preserve in single-dose containers of Type I glass.
Labeling
Label it to indicate that the Injection is to be diluted with a suitable parenteral vehicle prior to intravenous infusion.
Identification
Transfer a volume of Injection to a suitable container, and dilute if necessary, with dilute methanol (1 in 5) to obtain a test solution having a known concentration of 1.6 mg per mL. Prepare a Standard solution of USP Dopamine Hydrochloride RS in dilute methanol (1 in 5) having the same concentration as the test solution. The test solution so obtained responds to the Thin-layer Chromatographic Identification Test 201, a mixture of n-butyl alcohol, glacial acetic acid, and water (4:1:1) being used as the developing solvent and 5 µL each of the test solution and Standard solution being applied to the thin-layer chromatographic plate.
Bacterial endotoxins 85
It contains not more than 16.67 USP Endotoxin Units per mg of dopamine hydrochloride.
pH 791:
between 2.5 and 5.0.
Particulate matter 788:
meets the requirements for small-volume injections.
Other requirements
It meets the requirements under Injections 1.
Assay
Mobile phase
Prepare a filtered and degassed mixture of 0.005 M sodium 1-octanesulfonate in 1% glacial acetic acid and acetonitrile (87:13). Make adjustments if necessary (see System Suitability under Chromatography 621).
Standard preparation
Dissolve a suitable quantity of USP Dopamine Hydrochloride RS, accurately weighed, in Mobile phase to obtain a solution having a concentration of about 1.6 mg per mL. Pipet 10 mL of this solution into a 100-mL volumetric flask, dilute with Mobile phase to volume, and mix to obtain a Standard preparation having a known concentration of about 0.16 mg of dopamine hydrochloride per mL.
System suitability solution
Prepare a solution of benzoic acid in methanol containing about 20 mg per mL. Dilute 1 volume of this solution with 3 volumes of the Mobile phase to obtain a solution having a final concentration of about 5 mg per mL. Transfer 10.0 mL of this solution and 10.0 mL of a Standard solution containing 1.6 mg of USP Dopamine Hydrochloride RS per mL to a 100-mL volumetric flask, dilute with Mobile phase to volume, and mix.
Assay preparation
Transfer an accurately measured volume of Injection, equivalent to about 16 mg of dopamine hydrochloride, to a 100-mL volumetric flask, dilute with Mobile phase to volume, and mix.
Chromatographic system
(see Chromatography 621)The liquid chromatograph is equipped with a 280-nm detector and a 4-mm × 30-cm column packed with packing L1. The flow rate is about 1.5 mL per minute. Chromatograph the System suitability solution, and record the peak responses as directed under Procedure: the resolution, R, between benzoic acid and dopamine hydrochloride is not less than 4.0. Chromatograph the Standard preparation, and record the peak responses as directed under Procedure: the relative standard deviation for replicate injections is not more than 3.0%.
Procedure
Separately inject equal volumes (about 40 µL) of the Standard preparation and the Assay preparation into the chromatograph, record the chromatograms, and measure the responses for the major peaks. Calculate the quantity, in mg, of C8H11NO2·HCl in each mL of the Injection taken by the formula:
(100C / V)(rU / rS)
in which C is the concentration, in mg per mL, of USP Dopamine Hydrochloride RS in the Standard preparation; V is the volume, in mL, of Injection taken; and rU and rS are the responses of dopamine hydrochloride obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information
Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 2972
|