Determination of Sulphate in Beverages by Spectrophotometric Flow Injection Analysis

Saisunee Liawruangrath, Wilaiwan Phakthong
2006 FIA研究懇談会会誌  
An inexpensive FI-manifold and a minicolumn packed with cation exchanger resin with spectrophotometric detection are described for the determination of sulphate ions. It is based on the competitive reaction of SO 4 2and methythymol blue (MTB) with barium(II) in aqueous solution. Measurements were made at 610 nm. Conditions for the quantitation of sulphate ions were optimized using univariate and simplex methods. The cation exchange minicolumn was used to overcome some possible cationic
more » ... s. Linear calibration graphs over the range of 5-25 mg/l SO 4 2were established with the regression equation (n=5) Y=2.3172X-3.6798 (r=0.9963). The detection limit of 0.81 mg/l SO 4 2respectively together with the RSD of 2.09 % for 10 mg/l SO 4 2-(N=10) were obtained. The proposed method has been applied satisfactorily to the determination of SO 4 2in commercial beverages. Results obtained by the recommended method were in excellent agreement with those obtained by the reference method verified by using student t-test.
doi:10.24688/jfia.23.2_107 fatcat:nwtcb4lixvdevpvabjjm56z5om