Dimethyl Sulfoxide Irrigation
»Dimethyl Sulfoxide Irrigation is a sterile solution of Dimethyl Sulfoxide in Water for Injection.It contains not less than 95.0percent and not more than 105.0percent of the labeled amount of C2H6OS.
Packaging and storage— Preserve in single-dose containers,and store at controlled room temperature,protected from strong light.
Labeling— Label it to indicate prominently that it is not intended for injection.
Identification— Aportion of the Assay preparation,chromatographed as directed in the Assay,exhibits a major peak for dimethyl sulfoxide,the retention time of which is identical with that exhibited by the Standard preparation.
Bacterial endotoxins á85ñ It contains not more than 0.5Endotoxin Unit per mL.
Sterility á71ñ: meets the requirements.
pHá791ñ: between 5.0and 7.0,when diluted with water to obtain a solution containing 50mg of dimethyl sulfoxide per mL.
Assay—
Standard preparation— Dissolve an accurately weighed quantity of USP Dimethyl Sulfoxide RSin acetone,and dilute quantitatively with acetone to obtain a solution having a known concentration of about 80mg per mL.
Assay preparation— Transfer an accurately measured volume of Dimethyl Sulfoxide Irrigation,equivalent to about 2g of dimethyl sulfoxide,to a 25-mLvolumetric flask,dilute with acetone to volume,and mix.
Chromatographic system (see Chromatography á621ñ)—Proceed as directed in the test for Dimethyl sulfoneunder Dimethyl Sulfoxide.The relative standard deviation for replicate injections of the Standard preparationis not more than 2.0%.
Procedure— Introduce equal volumes (about 1.0µL)of the Standard preparationand the Test preparationinto the gas chromatograph.Measure the peak responses,at corresponding retention times,so obtained,and calculate the quantity,in mg,of C2H6OSin each mLof Dimethyl Sulfoxide Irrigation taken by the formula:
25(C/V)(rU/rS),
in which Cis the concentration,in mg per mL,of USP Dimethyl Sulfoxide RSin the Standard preparation;Vis the volume,in mL,of Dimethyl Sulfoxide Irrigation taken;and rUand rSare the peak responses from the Assay preparationand the Standard preparation,respectively.
Auxiliary Information— Staff Liaison:Lawrence Evans,III,Ph.D.,Scientist
Expert Committee:(PA6)Pharmaceutical Analysis 6
USP28–NF23Page 663
Phone Number:1-301-816-8389