The regression equation was ip(Sb(V))(A) = 0.7675 + 0.09159C Sb(V)(pg L−1) with a R2 value of 0.9906. RSD were 3.2% for 5 pg L−1Sb (V) with eight repetitive measurements. Under the optimized conditions, the detection limit was 0.2 pg L−1(1.64 fmol L−1).