Dynabeads SCX feature a surface optimized for binding and fractionation of intricate protein and peptide mixtures. Using strong cationic exchange (SCX), these magnetic beads separate proteomic samples based on isoelectric point and net charge differences, in preparation for downstream analyses such as mass spectrometry, HPLC or 1D/2D gel electrophoresis. They join and add functionality to an existing magnetic bead chromatography product line, which includes products for cation exchange, anion exchange and hydrophobic capture. Beads with different surface characteristics can be combined to isolate different fractions from the same sample, allowing for step-wise reduction of sample complexity.