An automatic system for acidity determination based on sequential injection titration and the monosegmented flow approach

作者：Kozak Joanna^*; Wojtowicz Marzena; Gawenda Nadzieja; Koscielniak Pawel

来源：Talanta, 2011, 84(5): 1379-1383.

DOI：10.1016/j.talanta.2011.03.069

• Sequential injection analysis
• Titration
• Monosegmented flow analysis
• Acidity

An automatic sequential injection system, combining monosegmented flow analysis, sequential injection analysis and sequential injection titration is proposed for acidity determination. The system enables controllable sample dilution and generation of standards of required concentration in a monosegmented sequential injection manner, sequential injection titration of the prepared solutions, data collecting, and handling. It has been tested on spectrophotometric determination of acetic, citric and phosphoric acids with sodium hydroxide used as a titrant and phenolphthalein or thymolphthalein (in the case of phosphoric acid determination) as indicators. Accuracy better than vertical bar 4.4 vertical bar% (RE) and repeatability better than 2.9% (RSD) have been obtained. It has been applied to the determination of total acidity in vinegars and various soft drinks. The system provides low sample (less than 0.3 mL) consumption. On average, analysis of a sample takes several minutes.

• 出版日期2011-6-15