This research aims to use chemical reaction to determine some of beta lactam antibiotics which include cephalexin and ceftriaxone in some pharmaceuticals by formation Prussian Blue complexes and using them for the UV-Vis., determination of drugs at wavelengths range (700- 720)nm by reaction them with FeCl3 in the presence of reagent K3[Fe(CN)6] in acid media . The optimal experimental conditions for the complex formation have been studied such as volume of HCl , K3[Fe(CN)6] , FeCl3 ,temperature and reaction time .Analytical figures of merits obtained on applying the developed procedure for cephalexin and ceftriaxone resp. are Linearity,(2-10),(1-7)?g.ml-1 LOD(0.0601,0.0330) ?g.ml-1. The developed procedure has been successfully applied to the determination of the antibiotics Cephalexin and Ceftriaxone in pharmaceutical preparations , Cephalexin and Gramocef using direct and standard additions method. The analytical results match well with the drug contents as indicated by recovery percent had been found as follows (103.50%,93.27%.) for cephalexin, and ceftriaxone resp..
