H-Point Standard Addition Method for Simultaneous Determination of Sodium Benzoate and Potassium Sorbate

Abstract

H-point standard addition method (HPSAM) can be used as a method of choice for the development of simultaneous determination of sodium benzoate and potassium sorbate concentrations because of its precision, accuracy, selectivity, and rapidity, in addition to its simplicity. HPSAM is based on twowavelength spectrophotometry and the standard addition method. Analyte concentrations to be determined were measured simultaneously using ultravioletvisible spectrophotometry at wavelength pairs selected; the standard calibration curve of interference is needed to calculate the concentration of interference. The data obtained were processed using a mathematical calculation. Potassium sorbate was selected as the analyte and sodium benzoate was chosen as interference because it showed better accuracy. Simultaneous determination of the concentration of sodium benzoate and potassium sorbate with HPSAM produced selected wavelength pairs at 212.2 and 233.4 nm. Sodium benzoate and potassium sorbate in some synthetic mixtures were determined simultaneously in the range of 4 and 1-1.5 mg/L, respectively, with good precision and accuracy.