Agilent Poroshell columns are ideal for fast separations of proteins and peptides because the unique particle allows for fast flow rates to be used while maintaining sharp, efficient peaks. Peptides and proteins are typically separated slowly to reduce the potential peak broadening of these slow diffusing analytes. But Poroshell columns use a unique particle made with a layer of porous silica on a solid core of silica. This reduces the diffusion distance for proteins making practical rapid HPLC separations of peptides and proteins up to 500–1,000 kDA. Poroshell 300SB C18, C8, C3, and 300Extend columns provide excellent stability and selectivity choices with TFA and formic acid mobile faces. Poroshell 300Extend C18 columns can be used at varying pH levels for unique separations and additional selectivity choices.