A brief review on dual wavelength spectrophotometry: The simultaneous estimation method and its application

The dual wavelength spectrophotometry is developed and validated for simultaneous estimation of various combinations of two drugs. Dual wavelength method is used to eliminate interference due to absorbance of other drug at sampling wavelengths for one drug. Two wavelengths are selected for each drug in such a way that the difference in absorbance is zero for the second drug. The principle for dual wavelength method is the absorbance difference between two points on the mixture spectra is directly proportional to the concentration of the component of interest and independent of interfering component. The Following review article contains a brief regarding dual wavelength spectrophotometry introduction, principle, examples and application of different pharmaceutical, organic and inorganic compounds.