Superspher® RP-select B is a highly reproducible traditionally produced spherical silica gel carriers with reversed phase properties and the hydrophobicity of a C-8 phase. This carrier is very well suited for the separation of basic compounds, but with still good properties for the determination of neutral and acidic compounds. The high performance silica carrier with a particle size of 4µm yields an excellent pressure/separation performance ratio.This sorbent is packed into a LiChroCART® 125-4 HPLC cartridge. The connection to the HPLC system is being accomplished by use of the manu-CART® NT cartrige holder (1.51486).