Novel Stationary Phases

For decades, liquid chromatography stationary phase design has been dominated by the idea of elimination of multiple, or “unwanted”, interactions that occur in mixed-mode separations. Reverse-phase chromatography is making the point of eliminating silanol interactions with amine-containing analytes by developing base-deactivated phases.

Within the same trend, adsorption interactions are considered undesirable as opposed to steric interactions in size-exclusion chromatography, and non-ionic interactions are generally viewed as complications in ion-exchange and ion-exclusion chromatography.

However, there are ways to benefit from multiple interactions on the stationary phase. SiELC introduces Primesep™ HPLC columns, specifically designed for mixed-mode separations and capable of separating a tremendous range of compounds by different separation modes based only upon mobile phase selection.

Acidic

Columns with negatively charged functional groups due to the embedded anionic ion-pairing reagent.

Primesep A – Strongest acidic phase

Primesep 100 – Strong acidic phase

Primesep 200 – Medium acidic phase

Choose the correct column by the functional group acidity to match the pKa value of your basic compounds.

Basic

Columns with positively charged functional groups.

Primesep B2
Weak basic column for ammonium acetate buffered solution.

Complex

Column with unique unparallel selectivity.

Primesep C
Combined reversed-phase and complex formation properties for interaction with amines, sulphonium, phosphonium and metal ions.

Phenyl

Three interactions within one column:

• reversed-phase
• pi-pi
• strong cation exchange

Primesep P

Choose for separation of structural isomers of aromatic compounds.