Based on high-purity NUCLEODUR silica gel, a polar group was embedded in a hydrophobic C18 modification. As a result, this HPLC phase shows steric and an increased polar selectivity. This HPLC phase shows a good performance under high aqueous conditions. It is a hydrophobic phase with pronounced hydrophilic properties. Separation mechanism based on hydrophobic (van der Waals) and polar interactions. Suitable for LC/MS due to low bleeding characteristics.