This method is used to determine arsenite (As(III)), and arsenate (As(V)) in water.

This method uses a 50-mm column with strong anion exchange packing to rapidly separate arsenite (As(III)) and arsenate (As(V)). A malonate/acetate mobile phase is used to separate the species in about three minutes using high performance liquid chromatography.
However, dimethylarsinate (DMA) and monomethylarsonate (MMA), if present, are unresolved and are eluted concurrently with As(III) and As(V).

Applicable Conc Range: MDL to 100 µg/L

Detection limits:  0.6 µg/L As(III), 0.5 µg/L As(V)