Spectrophotometric estimation of Ambroxol Hydrochloride, Guaifenesin and Levosalbutamol Sulphatein syrup

This study proposes a method for estimation of Ambroxol HCl, Guaifenesin and Levosalbutamol sulphate in syrup form. The study was done by combining three spectrophotometric methods viz use of first order derivative and colorimetry. Absorption of Guaifenesin and Levosalbutamol sulphate were found to be zero at 323 nm, thus enabling the measurement of Ambroxol HCl, using specific absorbance in first order spectrum. Same way absorption of Ambroxol HCl and Levosalbutamol sulphate were found to be zero at 276 nm, thus enabling the measurement of Guaifenesin using specific absorbance in first order spectrum. For colorimetric measurement of Levosalbutamol Sulphate, a colored substance was obtained by coupling the oxidized product of Levosalbutamol sulphate with 4-aminoantipyrine and Potassium ferricyanide and its absorption was measured at 503 nm. The proposed method was statistically validated in accordance with ICH guidelines and results were found to be satisfactory for accuracy, precision and specificity.