Sunrise Series Overview
Sunrise columns are very unique. Silanol Activity Control (SAC) technology leads not only adding an interaction by silanol groups but also a symmetrical peak forbasic compounds.
A long chain C28 phase shows high steric selectivity and larger retention for fat-soluble compounds than a C18 phase.
Both C18-SAC and C28 phase can achieve unique separation which a conventional C18 cannot do.
In general, the silanol group remaining in the silica-based stationary phase in such as C18 (ODS) has been the cause of adsorption and peak tailing of a basic compound. Because silanol groups in proximity to the hydrophobic group is poorly hydrated, it indicates a high adsorption properties.
For reducing the effect of the residual silanol groups, a variety of end-capping techniques have been developed.
ChromaNik developed the SAC technology that only silanol groups with high absorption activity were selectively reduced and richly hydrated silanol groups without high absorption activity remained.
This technology allowed that a basic compound was separated without any peak tailing. Furthermore, not only hydrophobic interaction but also hydrogen bonding capacity and ion exchange interaction by richly hydrated silanol groups worked on reversed phase separation.