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[Determination of dimethyl fumarate in bakery food by d-SPE-HPLC-PDA].

OBJECTIVE
To establish a simple and rapid pretreatment method with dispersive solid phase extraction ( d-SPE) by HPLC for determination of dimethyl fumarate in bakery foods.


METHODS
Dimethyl fumarate in samples was ultrasonically extracted by methanol, and cleaned up with d-SPE. Then, it was separated on C18 chromatographic column (4.6 mm x 25 mm, 5 μm) with a mixture of methanol--0.03 mol/L sodium acetate and 0.008 mol/L tetrabutyl ammonium bromide (40: 60, V/V) as mobile phase. The photodiode array detector was used in the determination under λ = 220 nm.


RESULTS
In the linear range of 0.1 -25 μg/ml, the correlation coefficients was r > 0.999, and the average recoveries of the spiked samples were in the range of 82.8% - 107.5% with relative standard deviations (RSD) in the range of 3.30% - 7.30% (n = 6). The limit of detection ( LOD) was 0.4 mg/kg, and the limit of quantification was 1.0 mg/kg.


CONCLUSION
The method is simple, rapid, sensitive and accurate, and suitable for determine dimethyl fumarate in bakery foods.