Unison UK-Amino is a 3µm particle size, polymer coated silica, with the Amino Ligand bonded using a proprietary method and offers exceptional durability, even in highly aqueous mobile phases. As well as being exceptionally stable the phase can be packed to very high efficiencies, and shows very high resolution of both saccharides and oligosaccharides. Unison UK-Amino has been used for both sugar analysis in foodstuffs as well as glycobiology. The use of simple water:acetonitrile mobile phases makes the applications amenable to a wide range of detection techniques including Corona CAD, ELSD, Fluorescence and Mass Spectrometry.
Silica‐based aminopropyl columns have been used for a long time for carbohydrate separation. However, these aminopropyl columns often demonstrate poor stability and lifetime due to "column bleeding", resulting in the rapid deterioration in retention as a result of ligand desorption under aqueous elution. Unison UK‐Amino offers a different approach from conventional columns with high durability against aqueous eluant. As the first attached chromatogram demonstrates columns experience a significant decline in retention when an aqueous mobile phase elutes through the column. UK‐Amino, on the other hand, does not show any change in separation or retention. UK‐Amino's phase design not only provides analytical power, but the 3μm particle, high‐resolution packing has other benefits, minimising LC‐MS and LC‐ELSD noise levels due to the elimination of column bleed. UK‐Amino can be applied to aqueous normal phase conditions, and separation optimisation is possible when compared to ODS columns using reversed‐phase mode. Significantly improved results can be expected from the UK-Amino column.
The phase is available packed in columns with dimensions from 50µm ID to 20mm and lengths from 10mm to 500mm (not all lengths are available in all IDs).
UK-Amino can be useful in the analysis of mixtures of compounds other than sugars (second chromatogram), such as alcohols, water and fat soluble vitamins and steroids.
Amino stationary phases generally employ both a normal phase separation mode and an anion exchange mode derived from the amino groups. In the example shown in the second chromatogram attached there are two methods to separate ascorbic acid and its isomer isoascorbic acid (erythorbic acid) using Unison UK‐Amino. In the normal phase mode, retention deteriorates as the polarity in the mobile phase rises. However, as the acetonitrile partition rises, retention increases and the two compounds completely separate at 75% acetonitrile. Moreover, the elution order is reversed compared to the anion exchange mode, due to the difference in interactions. In anion exchange mode, retention deteriorates as the ionic strength increases and pH driven ionic interactions grow weaker (in this case, high acidic density = low pH). In this example, the two compounds are completely separated with only a 0.5% acetic acid aqueous solution. UK-Amino is one of an exceptional range of packings and columns from the leading Japanese Manufacturer of Ultra High Performance HPLC columns, Imtakt Corporation and are available exclusively in the UK from ARC Sciences Ltd. For more information click the links or email enquiries@arcsciences.com