BIT – Borate Ion Trap
- High borate trapping capacity
- Easy installation between pump and injector
- 4 x 50 mm column, 10 µm resin
In carbohydrate analysis, the peak shape of certain sugars, such as mannose, sugar alcohols and fructose, are deteriorated when traces of borate are in the solvent. To eliminate the presence of borate ions in hydroxide eluents and to assure optimal performance of your HPAEC-PAD carbohydrate analysis, Antec Scientific introduced the borate ion trap column.
The borate ion trap column is based on a 10 µm polymeric resin functionalized with polyol groups with a high borate trapping capacity. The trap is available as 4 x 50 mm column and is installed inline in the HPAEC-PAD system between pump and injector. The typical back pressure of the trap at 0.7 mL/min and room temperature ranges between 17 – 22 bar.
The performance of the SweetSep™ borate ion trap is demonstrated in figure 1 for the monosaccharide analysis. The hydroxide eluent was intentionally contaminated with 10 ppb of borate. Without a borate ion trap in the system, significant tailing of the mannose peak is evident, with the trap column installed this borate-induced tailing is eliminated.
Fig 1. Analysis of carbohydrates with and without a SweetSep™ borate ion trap column. The peak of mannose shows significantly less tailing in the top chromatogram.
Monosaccharides are separated on a SweetSep™ AEX20 column using a 12 mM NaOH eluent containing 10 ppb borate (30°C, 0.7 mL/min). The additional borate ion trap column is placed before the autosampler, just after the HPLC pump. Injected sample: 10 µL of a 10 µM monosaccharides mix in DI water (fucose, 2-deoxy-glucose, galactosamine, glucosamine, galactose, glucose and mannose).
Borate ions
The majority of boron is present as boric acid at neutral pH. Borate is not very conductive in the form of boric acid, therefore small traces of borate in the low ppb range will not significantly affect the resistivity of the deionized water produced with the marginal resin bed. For that reason, the operator of the deionized water system in an analytical lab may be unaware of the fact that borate is in the deionized water they are using to prepare the eluent
In addition, the use of borosilicate glass bottles should be avoided at all time in HPAEC-PAD analysis, because borate can leach out of the glassware at high pH. For that reason, our ALEXYS Carbohydrate analyzer is equipped with polypropylene copolymer (PPCO) eluent bottles. These PPCO plastic bottles are inert at high pH.