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Cations and Anions Simultaneously

Your selection indicates that you wish to measure both cationic and anionic substances. DGT passive samplers which use a mixed binding layer of Chelex and a metal oxide are capable of measuring simultaneously Al, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, U, Zn, As, phosphate, Se(IV), Sb(V), Mo(VI), V(V), W(VI) and rare earth elements. Three types of DGT passive samplers with different mixed binding layers are available. As they all contain Chelex they measure cations equally well, but performance for the oxyanions varies slightly, depending on the conditions.

Chelex/iron oxide (ferrihydrite) Simplest elution, as it only involves acid. Particularly good for cations and phosphate, and for freshwaters and soils. Performance in seawater for oxyanions declines for longer deployments.
For deployments in waters you will need device LSNY-NP
For deployment in soilsA you will need device LSLY-NP
For deployments in sedimentsB you will need LSPY-NP

Chelex/titanium oxide (Metsorb) Performs well for a range of water types, more complicated sequential elution involving acid and base.

For deployments in all types of waters you will need device LSNX-NP
For deployment in soilsA you will need device LSLX-NP
For deployments in sedimentsB you will need LSPX-NP

Chelex/zirconium oxide Performs well for a range of water types, most complicated sequential elution involves acid, an oxidant and base.

Note that for most waters it is only possible to measure Ca and Mg using very short deployment times (<24 hours) because their high concentrations soon saturate the resin (see Dahlqvist, 2002, Jiménez-Piedrahita, 2017).

Probes that incorporate binding layers for both sulfide and cationic and/or anionic substances can be fabricated on request.

Some elements or oxidation states, including As(III), Cr(VI), Hg or CH3Hg, nitrate, sulphide, or Tc require specialist devices. See individual links:

As(III)          Cr(VI)         Hg or CH3Hg         nitrate         sulphide         Tc

Detailed instructions for the use of most DGT passive samplers are available.

AThese soil devices are designed for deployment in homogenised hydrated soil samples.

BThe sediment probes can be inserted directly into sediment and have a large enough area (exposure window 150 x 18 mm) to be capable of providing spatial information, e.g. vertical profiles or 2-D images. They have also been used to obtain similar information in hydrated soils (e.g. Luo et al., 2013).