Commercially available from Difco Laboratories, Box 1058A, Detroit, MI 48232; BBL, Division of Bioquest, P.O. Box 234, Cockeysville, MD 21030; ICN Nutritional Biochemicals, 26201 Miles Road, Cleveland, OH 44128; SchwartzMann, Orangeburg, NY 10962; and Calbiochem, 10933 N. Torrey Pines Road, La Jolla, CA 93037. Obtain Penicillin G reference standard from U.S.P. reference standards, 12601 Twin Brook Parkway, Rockville, MD 20852.
Original Source: Bacteriological Analytical Manual, 8th Edition, Revision A, 1998.