An Open Tubular Ion Chromatograph
- Publication date
- 2014
- Publisher
Abstract
We describe an open tubular ion chromatograph
(OTIC) that uses
anion exchange latex coated 5 μm radius silica and 9.8 μm
radius poly(methyl methacrylate) tubes and automated time/pressure
based hydrodynamic injection for pL–nL scale injections. It
is routinely possible to generate 50 000 plates or more (up
to 150 000 plates/m, columns between 0.3 and 0.8 m have been
used), and as such, fast separations are possible, comparable to or
in some cases better than the current practice of IC. With an optimized
admittance detector, nonsuppressed detection permits LODs of submicromolar
to double digit micromolar for a variety of analytes. However, large
volume injections are possible and can significantly improve on this.
A variety of eluents, the use of organic modifiers, and variations
of eluent pH can be used to tailor a given separation. The approach
is discussed in the context of extraterrestrial exploration, especially
Mars, where the existence of large amounts of perchlorate in the soil
needs to be confirmed. These columns can survive drying and freezing,
and small footprint, low power consumption, and simplicity make OTIC
a good candidate for such a mission