U.S. PHARMACOPEIA

Search USP29  
Penicillin G Benzathine Oral Suspension
» Penicillin G Benzathine Oral Suspension contains not less than 90.0 percent and not more than 120.0 percent 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.
Identification— Mix a portion of it with methanol to obtain a solution containing about 3000 Penicillin G Units per mL. Apply 20 µL of this test solution and 20 µL of a Standard solution of USP Penicillin G Benzathine RS in methanol containing 2.5 mg per mL to a suitable thin-layer chromatographic plate (see Chromatography 621) 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 20 g of tartaric acid and 1.7 g of bismuth subnitrate in 80 mL of water. Add 2.5 mL of this solution, 2.5 mL of potassium iodide solution (4 in 10), and 10 g of tartaric acid to 50 mL of water, and mix. Examine the chromatograms: the principal spot obtained from the test solution corresponds in RF value to that obtained from the Standard solution.
Uniformity of dosage units 905—
FOR SUSPENSION PACKAGED IN SINGLE-UNIT CONTAINERS : meets the requirements.
Deliverable volume 698: meets the requirements.
pH 791: between 6.0 and 7.0.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Assay—
Standard preparation— Using Penicillin G Potassium RS, prepare as directed for Standard preparation under Iodometric Assay—Antibiotics 425.
Assay preparation— Dilute an accurately measured volume of Oral Suspension, freshly mixed and free from air bubbles, quantitatively with 1.0 N sodium hydroxide to obtain a solution having a concentration of about 2000 Penicillin G Units per mL. Pipet 2 mL of this solution into a glass-stoppered, 125-mL conical flask.
Blank preparation— Dilute an accurately measured volume of Oral Suspension, freshly mixed and free from air bubbles, quantitatively with Buffer No. 1 to obtain a suspension containing about 2000 Penicillin G Units per mL. Pipet 2 mL of this solution into a glass-stoppered, 125-mL conical flask.
Procedure— Proceed as directed for Procedure under Iodometric Assay—Antibiotics 425, except in performing the Inactivation and titration to omit the addition of 1.0 N sodium hydroxide to the Assay preparation, and in performing the Blank determination to use the Blank preparation in place of the Assay preparation. Calculate the quantity, in Penicillin G Units, in each mL of the Oral Suspension taken by the formula:
(L / 2D)(F)(B I),
in which L is the labeled quantity, in Penicillin G Units per mL, in the Oral Suspension taken, and D is the concentration, in Penicillin G Units per mL, of the Assay preparation on the basis of the labeled quantity in the Oral Suspension and the extent of dilution.
Auxiliary Information— Staff Liaison : Brian D. Gilbert, Ph.D., Scientist
Expert Committee : (MDANT05) Monograph Development-Antibiotics
USP29–NF24 Page 1655
Phone Number : 1-301-816-8223