Glutaral Concentrate
;)
Pentanedial.
Pentanedial [111-30-8].
»Glutaral Concentrate is a solution of glutaraldehyde in Purified Water.It contains not less than 100.0percent and not more than 104.0percent of the labeled amount,the labeled amount being 50.0g of C5H8O2per 100g of Concentrate.
Packaging and storage—
Preserve in tight containers,protected from light,and avoid exposure to excessive heat.
Labeling—
The label states that this article is not intended for direct administration to humans or animals.
Clarity of solution—
Transfer 5.0mLof Concentrate to a glass-stoppered,100-mLgraduated cylinder,add water to obtain 100mLof mixture,insert the stopper,and mix by inverting the graduated cylinder several times.Allow the bubbles to rise,and view downward through the solution against a dark background:the solution is clear.
Identification—
2,4-Dinitrophenylhydrazine reagent—
Add 4mLof sulfuric acid to 0.8g of 2,4-dinitrophenylhydrazine,then add 6mLof water,dropwise,with swirling.When dissolution is essentially complete,add 20mLof alcohol,mix,and filter.The filtrate is the 2,4-Dinitrophenylhydrazine reagent.
Procedure—
Add 0.4mLof Concentrate to 20mLof 2,4-Dinitrophenylhydrazine reagent,mix by swirling,and allow to stand for 5minutes.Collect the precipitate on a filter,and rinse thoroughly with alcohol.Dissolve the precipitate in 20mLof hot ethylene dichloride,filter,and cool the filtrate in an ice bath until crystallization occurs.Collect the precipitate on a filter.Redissolve the precipitate by refluxing with 30mLof acetone,filter,and cool the filtrate in an ice bath until crystallization occurs.Collect the precipitate on a filter:the 2,4-dinitrophenylhydrazone so obtained melts between 185
and 195,within a 3range (see Melting Range or Temperature á741ñ).
and 195,within a 3range (see Melting Range or Temperature á741ñ).
Acidity—
Transfer 60.0g to a conical flask,add phenolphthalein TS,and titrate with 0.10Nalcoholic potassium hydroxide to a pink endpoint that is permanent for not less than 15seconds:not more than 40mLof 0.10Npotassium hydroxide is consumed,corresponding to not more than 0.4%(w/w)of acid,calculated as acetic acid.
pHá791ñ:
between 3.7and 4.5.
Heavy metals á231ñ:
0.001%.
Assay—
Hydroxylamine hydrochloride solution—
Dissolve 35g of hydroxylamine hydrochloride in 150mLof water in a 1000-mLvolumetric flask,add isopropyl alcohol to volume,and mix.
Triethanolamine solution—
Transfer 65mLof triethanolamine to a glass-stoppered,1000-mLvolumetric flask,add water to volume,and mix.
Procedure—
To 500mLof Hydroxylamine hydrochloride solutionadd 15mLof a solution of bromophenol blue in alcohol (1in 2500),and add Triethanolamine solutionfrom a buret to obtain a neutralized solution that appears greenish blue by transmitted light.Transfer 65.0mLof the neutralized solution to a glass-stoppered,500-mLconical flask,add 50.0mLof Triethanolamine solution,purge with nitrogen,and insert the stopper.Add about 1.2g of Concentrate,accurately weighed,by means of a suitable weighing pipet,insert the stopper,and allow to stand for 60minutes,swirling the flask occasionally.Titrate with 0.5Nsulfuric acid VSto a greenish blue endpoint,and perform a blank determination (see Residual Titrationsunder Titrimetry á541ñ).Calculate the percentage,by weight,of C5H8O2in the Glutaral Concentrate taken by the formula:
[N(B–A)(0.05006)/W]100,
in which Nis the normality of the sulfuric acid;Band Aare the volumes,in mL,of 0.5Nsulfuric acid VSconsumed by the blank and specimen solution,respectively;0.05006is the mEq weight,in g per mEq,of glutaraldehyde;and Wis the weight,in g,of Concentrate taken.
Auxiliary Information—
Staff Liaison:Behnam Davani,Ph.D.,MBA,Senior Scientist
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 909
Pharmacopeial Forum:Volume No.28(3)Page 764
Phone Number:1-301-816-8394