Penicillin G Benzathine Oral Suspension, chemical structure, molecular formula, Reference Standards

Penicillin G Benzathine Oral Suspension

»Penicillin G Benzathine Oral Suspension contains not less than 90.0percent and not more than 120.0percent of the labeled amount of penicillin G.It contains one or more suitable buffers,colors,dispersants,flavors,and preservatives.

Packaging and storage— Preserve in tight containers.

USP Reference standards á11ñ— USP Penicillin G Benzathine RS.USP Penicillin G Potassium RS.

Identification— Mix a portion of it with methanol to obtain a solution containing about 3000Penicillin G Units per mL.Apply 20µLof this test solution and 20µLof a Standard solution of USP Penicillin G Benzathine RSin methanol containing 2.5mg per mLto a suitable thin-layer chromatographic plate (see Chromatography á621ñ)coated with a 0.25-mm layer of chromatographic silica gel,and allow the spots to dry.Using an unlined developing chamber,develop the chromatogram in a solvent system consisting of a mixture of methanol,acetonitrile,and ammonium hydroxide (70:30:3)until the solvent front has moved about three-fourths of the length of the plate.Remove the plate from the developing chamber,and allow to air-dry.Spray the plate uniformly with a spray reagent prepared as follows.Dissolve 20g of tartaric acid and 1.7g of bismuth subnitrate in 80mLof water.Add 2.5mLof this solution,2.5mLof potassium iodide solution (4in 10),and 10g of tartaric acid to 50mLof water,and mix.Examine the chromatograms:the principal spot obtained from the test solution corresponds in RFvalue to that obtained from the Standard solution.

Uniformity of dosage units á905ñ—

FOR SUSPENSION PACKAGED IN SINGLE-UNIT CONTAINERS :meets the requirements.

Deliverable volume á698ñ: meets the requirements.

pHá791ñ: between 6.0and 7.0.

Assay—

Standard preparation— Using Penicillin G Potassium RS,prepare as directed for Standard preparationunderIodometric Assay—Antibiotics á425ñ.

Assay preparation— Dilute an accurately measured volume of Oral Suspension,freshly mixed and free from air bubbles,quantitatively with 1.0Nsodium hydroxide to obtain a solution having a concentration of about 2000Penicillin G Units per mL.Pipet 2mLof this solution into a glass-stoppered,125-mLconical flask.

Blank preparation— Dilute an accurately measured volume of Oral Suspension,freshly mixed and free from air bubbles,quantitatively with Buffer No.1to obtain a suspension containing about 2000Penicillin G Units per mL.Pipet 2mLof this solution into a glass-stoppered,125-mLconical flask.

Procedure— Proceed as directed for Procedureunder Iodometric Assay—Antibiotics á425ñ,except in performing the Inactivation and titrationto omit the addition of 1.0Nsodium hydroxide to the Assay preparation,and in performing the Blank determinationto use the Blank preparationin place of the Assay preparation.Calculate the quantity,in Penicillin G Units,in each mLof the Oral Suspension taken by the formula:

(L/2D)(F)(B-I),

in which Lis the labeled quantity,in Penicillin G Units per mL,in the Oral Suspension taken,and Dis the concentration,in Penicillin G Units per mL,of the Assay preparationon the basis of the labeled quantity in the Oral Suspension and the extent of dilution.

Auxiliary Information— Staff Liaison:William W.Wright,Ph.D.,Scientific Fellow

Expert Committee:(PA7)Pharmaceutical Analysis 7

USP28–NF23Page 1485

Phone Number:1-301-816-8335