Spectrophotometric Method for Determination of Some Third Generation Cephalosporins Antibiotics Using Sodium Molybdate

Abstract

A simple, rapid and sensitive spectrophotometric method has been developed for
the quantitative determination of four drugs of pharmaceutical interest; cefotaxime Na,
cefoperazone Na, ceftazidime pentahydrate, ceftriaxone Na, 3rd generation cephalosporins
The method based on the reduction of the chromogenic agent, sodium molybdate (Mo6+)
'into molybdenum blue (Mo5+) the examined drugs in sulphuric acid medium and by aid of
heating in boiling water bath. The resulting "blue colored" products possess a
characteristic max at 680 nm, different factors are studied such as, effect of temperature,
time, surfactant and interference. Beers law is obeyed over the concentration range of 2 -
70 μg ml-'with molar absorpitivities ranging from 0.599 ×104 Lmol-1cm-1 - 1.794×104 Lmol-
1cm-1and Sandell sensitivities ranging from 0.02538 μg cm-2 - 0.1077μg cm-2. The proposed
method has been applied successfully for the determination of the examined drugs both in
pure form and in pharmaceutical formulations. The method also finds a good application
for urine and blood samples.