Fluorescence labeled capillary electrophoresis fingerprint analysis of sulfonamides residues in tea garden soil and tea

Abstract

A fluorescence labeled capillary electrophoresis fingerprint method for the analysis of sulfonamides residues in tea garden soil and tea was established by using o-phthalaldehyde (OPA) as precolumn derivatization reagent. The effects of background electrolyte concentration, pH, column temperature and voltage on the separation conditions were investigated. The optimum separation conditions were as follows: Glycine sodium hydroxide slow concentration: 20 mmol/L; pH: 9.0; Column temperature: 20 °C; Separation voltage: 17 kv, pressure: 50 mbar, injection time: 8 s. Under the established optimal conditions, 13 sulfonamide derivatives could be separated efficiently within 9 min, and the linear range is 0.35~100μg/kg, the detection limit (signal-to-noise ratio is 3) is in the range of 0.12-0.25 μg/kg, the quantitative limit (signal-to-noise ratio is 10) is in the range of 0.35-0.70μg/kg.