[Determination of 3-nitropropionic acid in moldy sugarcane by gel filtration-high performance liquid chromatography]

To establish a method for determination of 3-nitropropionic acid(3-NPA) in moldy sugarcane by gel permeation chromatography-high performance liquid chromatography(GPC-HPLC) method.

Samples were extracted by acetonitrile and cleaned up by GPC-HPLC. The sample extract was separated on an Agilent Eclipse plus C_(18) column(4.6 mm×150 mm, 5 μm), keeping the column temperature at 40℃ with an injection volume of 10 μL. The condition of mobile phase was KH_2PO_4 aqueous solution(0.02 mol/L, pH 3.0 with phosphoric acid) as mobile phase A and acetonitrile as mobile phase B for isocratic elution.

There was a good linearity of the calibration curve for 3-NPA in the range of 0.5-20.0 mg/kg with the correlation coefficient of 0.99989. The detection limit of the method was 0.05 mg/kg, and the limit of quantification was 0.15 mg/kg. The average recovery at three spiked levels was in the range of 91.7%-99.4%, and the relative standard deviation was 7.23%-8.62%(n=6).

This method is stable and accurate, and is suitable for the detection of 3-nitropropionic acid in sugarcane.