Ascentis Express 5 micron ES-Cyano HPLC column is a high-speed, high-performance liquid chromatography column based on 90Å Fused-Core particles. The Fused-Core particle provides a thin porous shell of high-purity silica surrounding a solid silica core. This particle design exhibits very high column efficiency due to the shallow diffusion paths in the 0.6-micron thick porous shell and the overall particle size of 5-microns. The sterically protected, extensively endcapped diisopropyl-cyanopropylsilane stationary phase of Ascentis Express ES-Cyano provides a stable, reversed-phase packing that can be used for basic, acidic, or neutral compounds.. Limit: =80 °C temp. range. Application(s): HPLC: suitable. Sold in each. . . Sigma-Aldrich 50588-U Ascentis Express ES-Cyano, 5 Micron HPLC Column, 5 µm Particle Size, 4.6mm ID, 15cm Length. Country of Origin : United States. Part Number : 1179R64EA. Pack of : 1.