Loss on drying á731ñ
Dry about 100mg,accurately weighed,in a capillary-stoppered bottle in vacuum at a pressure not exceeding 5mm of mercury at 60

for 3hours:it loses not more than 3.0%of its weight.
Assay
Tetrabutylammonium hydrogen sulfate solution,Edetate disodium solution,pH7.5Phosphate buffer,Mobile phase,Standard preparation,System suitability solution,and Chromatographic system
Proceed as directed in the
Assayunder
Oxytetracycline.
Assay preparation 1
(where it is represented as being in a single-dose container)Constitute Oxytetracycline for Injection in a volume of water,accurately measured,corresponding to the volume of solvent specified in the labeling.Withdraw all of the withdrawable contents,using a suitable hypodermic needle and syringe,and dilute quantitatively with 0.01Nhydrochloric acid to obtain a solution having a concentration of about 0.2mg of oxytetracycline per mL.
Assay preparation 2
(where the label states the quantity of oxytetracycline in a given volume of constituted solution)Constitute Oxytetracycline for Injection in a volume of water,accurately measured,corresponding to the volume of solvent specified in the labeling.Dilute an accurately measured volume of the constituted solution quantitatively with 0.01Nhydrochloric acid to obtain a solution having a concentration of about 0.2mg of oxytetracycline per mL.
Procedure
Proceed as directed for
Procedurein the
Assayunder
Oxytetracycline.Calculate the quantity,in mg,of oxytetracycline (C
22H
24N
2O
9)withdrawn from the container or in the portion of constituted solution taken by the formula:
(L/D)(CP)(rU/rS),
in which
Lis the labeled quantity,in mg,of oxytetracycline (C
22H
24N
2O
9)in the container or in the portion of constituted solution taken;
Dis the concentration,in mg per mL,of oxytetracycline in
Assay preparation 1or in
Assay preparation 2,based on the labeled quantity in the container or in the portion of constituted solution taken,respectively,and the extent of dilution;and the other terms are as defined therein.