Simultaneous SPE-HPLC Determination of Residual Amounts of Plant Growth Regulators and Fungicides in Drink

A method for the simultaneous determination of 2 plant-growth regulators (carbendazim and 6-benzylaminopurine) and 2 fungicides (paclobutrazol and myclobutanil) in drinks by HPLC was proposed. The filtrate of sample was purified on GDX501 SPE column. The column was first rinsed with a mixed solution of H2O+CH3OH (80+20) and then eluted with CH3OH. The 4 compounds mentioned above were separated on Waters Symmetry C18 column with mixture of methanol and 5 mmol·L-1 phosphate buffer of pH 6 (67+33) as mobile phase. Linearity ranges for the 4 compounds were same between 1.0 and 50 mg·L-1, with detection limits (3S/N) of 0.24 (for carbendazim), 0.80 (for benzylaminopurine), 0.90 (for paclobutrazol) and 0.90 mg·L-1 (for myclobutanil). Sample of orange juice was analyzed by the proposed method, giving values of recovery in the range of 70.9%-104%, with RSD′s (n=6) less than 6%.