Erythromycin Tablets
»Erythromycin Tablets contain not less than 90.0percent and not more than 120.0percent of the labeled amount of C37H67NO13.
NOTE—Tablets that are enteric-coated meet the requirements for Erythromycin Delayed-Release Tablets.
Packaging and storage— Preserve in tight containers.
Identification— Prepare a test solution by mixing a quantity of finely powdered Tablets with methanol to obtain a concentration of about 2.5mg of erythromycin per mL.Proceed as directed in the Identificationtest under Erythromycin Delayed-Release Capsules,beginning with “Prepare a Standard solution of USP Erythromycin RS.”
Dissolution á711ñ—
Medium: 0.05MpH6.8phosphate buffer (see Buffer solutionsin the section Reagents,Indicators,and Solutions);900mL.
Apparatus 2: 50rpm.
Time: 60minutes.
Test solution— If necessary,dilute a filtered portion of the solution under test with Mediumto obtain a solution having a concentration of about 0.28mg of erythromycin per mL,and mix.
Standard solution— Dissolve an accurately weighed quantity of USP Erythromycin RSin methanol (not more than 1mLof methanol for each 14mg of the Reference Standard),and dilute with water,quantitatively and with mixing,to obtain a stock solution containing about 0.56mg per mL.Immediately prior to use,dilute the stock solution quantitatively with water to obtain a Standard solutionhaving a known concentration of about 0.28mg per mL.
Procedure— Transfer 5.0-mLportions of the Test solutionand the Standard solutionto separate 25-mLvolumetric flasks,and treat each as follows:Add 2.0mLof water,and allow to stand for 5minutes with intermittent swirling.Add 15.0mLof 0.25Nsodium hydroxide,dilute with Mediumto volume,and mix.Heat to 60for 5minutes,and allow to cool.Concomitantly determine the absorbances of these solutions at the wavelength of maximum absorbance at about 236nm,with a suitable spectrophotometer,using blank solutions similarly prepared,except that 2.0mLof 0.5Nsulfuric acid is substituted for the 2.0mLof water.Calculate the amount of C37H67NO13dissolved.
Tolerances— Not less than 70%(Q)of the labeled amount of C37H67NO13is dissolved in 60minutes.
Uniformity of dosage units á905ñ: meet the requirements.
Loss on drying á731ñ— Dry about 100mg of powdered Tablets in a capillary-stoppered bottle in vacuum at 60for 3hours:it loses not more than 5.0%of its weight.
Assay— Place not less than 4Tablets in a high-speed glass blender jar with 200mLof methanol,and blend for 3minutes.Add 300mLof Buffer No.3,and blend for 3minutes.Proceed as directed under Antibiotics—Microbial Assays á81ñ,using an accurately measured volume of this stock test solution diluted quantitatively with Buffer No.3to yield a Test Dilutionhaving a concentration assumed to be equal to the median dose level of the Standard.
Auxiliary Information— Staff Liaison:William W.Wright,Ph.D.,Scientific Fellow
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 761
Phone Number:1-301-816-8335