DETERMINATION OF PROCAINE PENICILLIN-G AND PENICILLIN-G BY 2ND DERIVATIVE SPECTROPHOTOMETRY IN PHARMACEUTICAL PRODUCTS

''Zero-crossing'' derivative spectrophotometry has been used for deter mining binary mixtures of penicillin G and procaine penicillin G. The procedure is rapid, simple, nondestructive, and does not require resol utions of equations. Calibration graphs are linear between 2.0 and 50. 0 mug mL-1 of the penicillin G at 226.0 nm, and between 2.0 and 100.0 mug mL-1 of procaine penicillin G at 319.0 nm, in the presence of each other. A complete and exhaustive statistical analysis of the experime ntal data was realized to demonstrate the validity of method. The meth od was successfully applied to assay commercial injections of these dr ugs.