Merck’s Aluspher^® RP-select B HPLC column is an alkali-stable reversed-phase stationary phase designed for the chromatographic separation of neutral, basic and acidic compounds under neutral conditions. The stationary phase is based on spherical alumina particles, coated with polybutadiene (PBD). Due to its extended pH-stability, Aluspher^® RP-select B allows the use of basic eluents, such as NaOH.