Demecarium Bromide Ophthalmic Solution
»Demecarium Bromide Ophthalmic Solution is a sterile,aqueous solution of Demecarium Bromide.It contains not less than 92.0percent and not more than 108.0percent of the labeled amount of C32H52Br2N4O4.It contains a suitable antimicrobial agent.
Packaging and storage—
Preserve in tight,light-resistant containers.
Identification—
A:
Mix about 10mLwith 12.5mLof 1Nsodium hydroxide,and proceed as directed in Identificationtest Bunder Demecarium Bromide,beginning with “reflux for 15minutes”:a violet-blue color is produced.
B:
To 10mLadd 5mLof a 1in 50solution of ammonium reineckate in methanol,and allow to stand for 30minutes with occasional swirling:a pink reineckate of demecarium forms,and it melts between 131
and 136,with decomposition.
and 136,with decomposition.
C:
It responds to the tests for Bromide á191ñ.
Sterility á71ñ:
meets the requirements.
Assay—
Into each of two 50-mLvolumetric flasks marked 1and 2pipet a volume of Ophthalmic Solution,equivalent to about 2.5mg of demecarium bromide.Into each of two additional 50-mLvolumetric flasks,marked 3and 4,pipet 5.0mLof a freshly prepared Standard solution made by dissolving about 50mg of USP Demecarium Bromide RS,accurately weighed,in 100.0mLof water.To flasks 1and 3,add 1Nsodium hydroxide to volume,and mix.Transfer 10.0mLof each of these solutions to separate glass-stoppered tubes,insert the stoppers loosely,heat the tubes in a water bath for 15minutes,then cool to room temperature.The concentration of USP Demecarium Bromide RSin the Standard solution is about 50µg per mL.To flasks 2and 4,add pH10.0alkaline borate buffer (see under Solutionsin the section Reagents,Indicators,and Solutions)to volume,and mix.Concomitantly determine the absorbances of the two sodium hydroxide solutions at the wavelength of maximum absorbance at about 292nm,with a suitable spectrophotometer,using the corresponding borate buffer solutions as the respective solvent blanks.Calculate the quantity,in mg,of C32H52Br2N4O4in each mLof the Ophthalmic Solution taken by the formula:
(50C/V)(AU/AS),
in which Cis the concentration,in mg per mL,of USP Demecarium Bromide RSin the Standard solution;Vis the volume,in mL,of Ophthalmic Solution taken;and AUand ASare the absorbances of the sodium hydroxide solution from the Ophthalmic Solution and the Standard solution,respectively.
Auxiliary Information—
Staff Liaison:Ravi Ravichandran,Ph.D.,Senior Scientist
Expert Committee:(PA3)Pharmaceutical Analysis 3
USP28–NF23Page 577
Phone Number:1-301-816-8330