Figure 2

Chromatogram of standard arsenic species. The separation was performed on CAPCELL PAC C18 MG II with 10 mM butane sulfonic sodium, 4 mM malonic acid, 4 mM tetramethylammonium hydroxide, and 0.5% methanol (pH 2.0). The signal peaks are as follows: As(V) (1), As(III) (2), MA(V) (3), DMA(V) (4), and AB (5).