A: Generally we would recommend a device with a mixed binding layer of Metsorb (TiO2) and Chelex. This is the most robust combination which generally performs well in both freshwater and seawater.
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
Details of the performance of this binding layer can be found in:
- G. Panther, W. W. Bennett, D. T. Welsh and P. R. Teasdale, Simultaneous measurement of trace metal and oxyanion concentrations in water using diffusive gradients in thin films with a chelex-metsorb mixed binding layer, Anal. Chem., 86: (2014), 427-434.
Although a binding layer that uses ferrihydrite instead of Metsorb has some performance limitations, especially for deployments longer than a few days in seawater, it does have advantages in some situations. Devices with a mixed Chelex and ferrihydrite binding layer are preferred where analysis is by total digestion of the binding layer, elution is restricted to a single acid step, or for phosphate where the final analysis is colorimetric.
For deployments in all types of 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