Simple, Sensitive and Rapid Spectrophotometric Determination of Albendazole Based on Redox and Complex Formation Using N-Bromosuccinimide

Two simple, sensitive and rapid methods are described for the determination of albendazole (ABZ) in bulk drug and in formulations using N-bromosuccinimide as the oxidimetric reagent. The methods involve the addition of a known excess of NBS to ABZ in HCl medium followed by estimation of the unreacted oxidant by two reaction schemes involving the use of iron(II) and thiocyanate (method A) or tiron (method B). In both methods, the absorbance is found to decrease linearly with ABZ concentration. Beer’s law is obeyed over the ranges 0.5-5.0 and 1-21 μg mL for method A and method B, respectively. The calculated molar absorptivity values are 4.8×10 and 1.1×10 L molcm for method A and method B, respectively. The limit of detection (LOD) and quantification (LOQ) are also reported for both methods. The RSD values for intra-day and inter-day precision studies were less than 2.0 and 3.0%, respectively. Both the methods were applied to the determination of ABZ in tablet preparations and the results were satisfactory, and were comparable with those obtained by the reference method. The accuracy and reliability of the proposed methods were further ascertained by recoveries studies, and the recoveries of the spiked drug ranged between 98.5 and 103.2%.