ABSTRACT
Four simple, accurate, sensitive, selective and economic spectroscopic methods were developed for determination of atorvastatin in bulk and dosage form. Procedures I and II determined the drug in presence of other three statins [lovastatin, pravastatin and simvastatin] as well. Procedure I is based on formation of a highly colored ion-pair complex with methylene blue dye that was extractable in chloroform. The absorbance of the complex was measured at 654 nm against a blank. Procedure II was based on the reaction of the drug with N-bromosuccinimide [NBS] in slightly acidic media producing a yellow colored product measured at 347 nm. Procedure III depended on formation of chloroform extractable salt with silver and copper cations, while procedure IV depended on AAS measurement of copper in the chloroform extractable salt formed between the drug and copper cation. Beer's law was obeyed in the ranges of 1-12, 3-84, 10-65, 12-80 and 40-200 micro g ml[-1] for procedures I, II, Ilia, Illb and IV respectively with correlation coefficient not less than 0.9991. The four methods hold well accuracy and precision when applied to the analysis of the drug in its dosage form with percentage recoveries ranged from 99.2 +/- 0.634 to 100.53 +/- 0.227