Abstract:

In this study, a high performance liquid chromatography （HPLC） method was established for the simultaneous determination of 5 sweeteners （saccharin sodium, aspartame, acesulfame, sucralose, and stevia） in oral care toothpaste. The mixed solution of water-methanol （volume ratio of 80∶20） was used as the extraction solvent. Ultrasonic parameters were as follows: time 20 min, temperature 40 ℃, and ultrasonic power 360 W. After ultrasonic extraction, solid phase extraction was used. The test was performed using the Thermo Scientific UltiMate 3000 liquid chromatography system with the DAD-3000 RS diode array detector. The chromatography was performed on Capcell Pak MG-Ⅱ C₁₈ column （250 mm×4.6 mm, 5 μm） at 35 ℃. The mobile phase consisted of 20 mmol/L ammonium acetate solution （pH 5.5） and methanol. The detection wavelength was 214 nm. The results of the methodology evaluation show that the precision RSD of the five sweeteners are all less than 5%. In the mass concentration range of 0.1-500 mg/L, the five sweeteners show good linear relationships, the correlation coefficients are distributed in the range of 0.999 4-0.999 8, and the detection limits are 0.05-0.20 mg/L. The recovery rates of the five sweeteners range from 97.08% to 105.53%, and RSD values in batches are all lower than 5%.

Key words: high performance liquid chromatography, simultaneous determination, toothpaste, sweetener, oral