Spectrophotometric determination of the aspirin and Atenolol in combined dosage forms

This work is concerned with the simultaneous determination of aspirin and atenolol in a combined dosage form, without prior separation, by three techniques. The first method is the application of simultaneous equation, where the linearity range for both the drugs was 2-16 mu g/ml. The second method depends on the application of area under the curve at selected wavelength range, 271 to 281nm and 222 to 232 nm, the linearity ranges for aspirin and atenolol were 6-18 mu g/ml and 8-16 mu g/ml, respectively. The third method is based on the derivative spectrophotometric method at zero crossing wavelengths. These methods are simple, accurate, and rapid, and they require no preliminary separation and can therefore be used for routine analysis of both drugs in quality control laboratories.