C44H46CaN4O18 958.93

2-Naphthacenecarboxamide, 4-(dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-3,5,6,10,12,12a-hexahydroxy-6-methyl-1,11-dioxo-, calcium salt, [4S-(4,4a,5,5a,6,12a)]-.
4-(Dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-3,5,6,10,12,12a-hexahydroxy-6-methyl-1,11-dioxo 2-naphthacenecarboxamide calcium salt [15251-48-6].

Packaging and storage— Preserve in tight, light-resistant containers, and store in a cool place.

USP Reference standards 11— USP Oxytetracycline RS.

Identification— Dissolve a suitable quantity in methanol to obtain a Test Solution containing 1 mg of oxytetracycline per mL, and proceed as directed for Method II under Identification—Tetracyclines 193.

Crystallinity 695: meets the requirements.

pH 791: between 6.0 and 8.0, in an aqueous suspension containing 25 mg per mL.

Water, Method I 921: between 8.0% and 14.0%.

Calcium content— Proceed as directed under Residue on Ignition 281, except to ignite at 550 ± 50 instead of at 800 ± 25: the weight of residue so obtained, multiplied by 0.2944, gives the equivalent of calcium in the Oxytetracycline Calcium taken. The calcium content is between 3.85% and 4.35%, calculated on the anhydrous basis.

Residual solvents 467: meets the requirements.

Assay— Dissolve an accurately weighed quantity of Oxytetracycline Calcium in an accurately measured volume of 0.1 N hydrochloric acid to obtain a stock solution having a concentration of about 1000 µg of oxytetracycline per mL. Proceed as directed for oxytetracycline under Antibiotics—Microbial 81, using an accurately measured volume of the stock solution diluted quantitatively and stepwise with water to yield a Test Dilution having a concentration assumed to be equal to the median dose level of the Standard.

Expert Committee : (MDANT05) Monograph Development-Antibiotics

USP29–NF24 Page 1618

Phone Number : 1-301-816-8223