Simple and rapid spectrophotometric assay of albendazole in pharmaceuticals using iodine and picric acid as CT complexing agents

Nagaraju Swamy,Kanakapura Basavaiah

doi:10.1590/s1984-82502014000400019

Abstract

Two simple, rapid and inexpensive spectrophotometric methods are described for the determination of albendazole (ALB) in bulk drug and in tablets. The methods are based on charge-transfer (CT) complexation reaction involving ALB as n-donor and iodine as σ-acceptor (method A) in dichloromethane or picric acid (PA) as π-acceptor (method B) in chloroform. The absorbance of CT complexes was measured at 380 nm for method A, and 415 nm for method B. The optimization of the experimental conditions is described. Under optimum conditions, Beer's law obeyed over the concentration ranges 8.0-240 and 2.4-42 μg mL-1 for method A and method B, respectively. The apparent molar absorptivity of CT complexes at the respective λmax are calculated to be 1.17×103 and 5.22×103 L mol-1cm-1 respectively, and the corresponding Sandell sensitivity values are 0.2273 and 0.0509 ng cm-2. The limits of detection (LOD) and quantification (LOQ) are calculated to be (0.69 and 2.08), and (0.10 and 0.30) μg mL-1 with method A, and method B, respectively. The intra-day and inter-day accuracy expressed as % RE and precision expressed as % RSD were less than 3%. The methods were applied to the determination of ALB in tablets.

Highlights

Albendazole (ALB), a benzimidazole carbamate (Figure 1), is a broad spectrum anthelmintic used in the treatment of threadworm, hookworm and tapeworm (International Pharmacopoeia, 1987; Jaime, William, 1988; Rang, Dale, Rither, 1999)
The drug is official in British Pharmacopoeia (British Pharmacopoeia, 2009), which describes a potentiometric titration with perchloric acid in formic acid-acetic acid medium
Alworm-400 (Medopharm Ltd., Malur, Method B (Using picric acid, PA) Aliquots of 0.2, 0.5, 1.0, 2.0, 3.0 and 3.5 mL of standard ALB solution (60 mg mL-1) were accurately added to 5 mL calibrated flasks using a microburette, and the total volume was adjusted to 3.5 mL with chloroform

Summary

INTRODUCTION

Albendazole (ALB), a benzimidazole carbamate (methyl-5-propyl thio-1H-benzimidazol-2-yl carbamate) (Figure 1), is a broad spectrum anthelmintic used in the treatment of threadworm, hookworm and tapeworm (International Pharmacopoeia, 1987; Jaime, William, 1988; Rang, Dale, Rither, 1999). The reported methods based on CT formation reaction (Zhao et al, 2001; Refat, Mohammed, Fathi, 2011) are less sensitive and applicable over narrow linear ranges Despite their wide applicability and ability to form stable and sensitive CT complexes with nitrogenous bases, and pharmaceutical substances (Ebeid et al, 1998; Abou, 2000; Regulska, Tarasiewicz, Puzanowska, 2002; El-Mammli, 2003; El- Yazbi et al, 2003; Abdel-Hay et al, 2004; Karuna et al, 2006; Rajendra, Basavaiah, Vinay, 2011; Johnson, Ukpe, 2011; Pinderjit, Rajanish, Harinder, 2011; Sameer, Basavaiah, 2011; Raghu, Basavaiah, 2012; Prashanth, Basavaiah, 2012) iodine, as a σ-acceptor and picric acid, a π-acceptor have not been applied for the spectrophotometric assay of ALB. Following the same procedure for tablets, the synthetic mixture solution was prepared, and a suitable aliquot was subjected to analysis by both methods (n=3), after appropriate dilution

AND DISCUSSION

METHOD VALIDATION

Method

Proposed methods