Spursil™ polar-modified phases are based on ultra high-purity silica and novel polar modification technology. The unique bonded phases maximize polar retention and selectivity, while virtually eliminating silanol activity. The resulting polar-modified packing material contains a surface which is easily "wetted" with polar eluents and can run in highly aqueous conditions. The polar group also seems to play a role in base deactivation. We have seen some evidence that hydrogen bonding occurs between certain polar linkers and the silica surface, thereby decreasing the interaction of such silanols with basic components in the sample. Additionally, polar-modified phases often provide selectivity quite different from standard C18 phases.

• Combine high-purity silica with unique polar modification technology
• Maintain characteristics of conventional reversed phases
• Unique selectivity and enhanced resolution
• Reduced silanol interactions and improved peak shape for basic analytes
• Stable retention in highly aqueous mobile phase conditions
• Enhanced retention for polar compounds
• Extended range pH stability
• Choose from a variety of selectivities & hardware formats

Standard reversed-phase columns, particularly C18 columns, often suffer from "phase collapse" and the retention of the compounds is severely diminished when used in combination with highly aqueous phases. This phenomenon is substantially reduced with Spursil™ because the polar modifications make the phase less hydrophobic and more wettable. Polar-modified phases remain fully extended in aqueous phases, allowing increased interaction between samples and the bonded phase. Spursil™ columns show good retention of polar compounds which tend to elute in the void volume on standard ODS phases.