Spectrophotometric Determination of Cefadroxil in Bulk and Dosage Forms using 2,4-Dinitrophenylhydrazine.

 Abstract:

An accurate, sensitive and  simple spectrophotometric method has been developed and validated for determination of cefadroxil (CFX) in bulk and pharmaceutical formulations. The method is based on the oxidation of 2,4-dinitrophenylhydrazine (DNP) using potassium periodate (PPI) to produce a diazonium salt which is coupled with CFX to form a colored  chromogen which was measured at 515 nm. Appropriate conditions were examined for the reaction to obtain maximum absorptivity and sensitivity. The optimum conditions were 1.5 mL of 0.1% 2,4-DNP, 1.5 mL of 0.15% PPI and 0.5 mL of 10 M NaOH solution at room temperature. The method was linear in a concentration range between 7.5-75 µg/mL with regression coefficient of 0.998 (n=5). The limit of detection (LOD) and limit of quantification (LOQ) were 0.89 and 2.7 µg/ml, respectively. The precision was satisfactory; the values of relative standard deviation (RSD) had not exceeded 2%. The average values of recovery study at three concentration levels were found to be in the range 98.6 ? 101.3 ± (0.28 – 0.14). The developed method was applied successfully for determination of CFX in capsules, tablets  and suspension, therefore, it could be used for routine analysis of the drug in pharmaceutical dosage forms.