Journal
ANALYTICAL CHEMISTRY
Volume 88, Issue 24, Pages 12013-12020Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.analchem.6b03669
Keywords
-
Categories
Funding
- NASA [NNX11AO66G]
- Thermo Fisher Scientific
- National Science Foundation [CHE-1506572]
- Development and Promotion of Science and Technology Talents Project (DPST), Thailand
- Division Of Chemistry
- Direct For Mathematical & Physical Scien [1506572] Funding Source: National Science Foundation
- NASA [139613, NNX11AO66G] Funding Source: Federal RePORTER
Ask authors/readers for more resources
We describe novel cycloolefin polymer (COP)-based open tubular capillary ion exchange columns. COP capillaries (inner diameter of 19-28 mu m) were successfully sulfonated at room temperature using a cocktail of ClSO3H (85-95% w/w) and HOAc or H2SO4. The cation exchange capacity is controlled by the sulfonation time and the sulfonation solution composition and can be as high as 300 pequiv/mm(2). Following sulfonation, the capillaries were coated with 65-nm-diameter anion exchanger (AEX) latex nanoparticles that attach electrostatically. The typical anion exchange capacities were similar to 20 pequiv/mm(2). The chromatographic behavior of the AEX latex-coated COP capillaries are greatly dependent on the degree of sulfonation. When the base is heavily sulfonated, neutrals elute after the anions. The position of the water dip varies with the degree of sulfonation; the elution order is normal (water dip appear before anions) only with lightly sulfonated columns. On silica (-SiOH) or poly(methyl methacrylate) (-COOH) surfaces, AEX latex attachment is not stable over long periods in significant concentrations of strong base (e.g., >= 10 mM NaOH). Latex attachment on sulfonated COP surfaces are much stronger; several types show sufficient binding to be used over long periods at practical eluent concentrations, paving the way for suppressed hydroxide eluent ion chromatography (IC), which is discussed in a companion paper. Another interesting feature of COP capillaries lies in their flexibility. If softened at modestly elevated temperatures (e.g., boiling water), they can be coiled down to <1 mm coil radii, revealing, for the first time, the beneficial effects, albeit small, of centrifugal force on mass transfer in open tubular columns.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available