ProPac SAX-10 4X250MM. Use Thermo Scientific™ ProPac™ SAX-10 LC Columns for exceptionally high resolution and efficiency when separating protein variants. Based on a nonporous 10µm core particle that provides pressure stability, ProPac columns can resolve isoforms that differ by a single charged residue. A thin, hydrophilic layer prevents unwanted secondary interactions. The grafted anion exchange surface provides pH-based selectivity control and fast mass transfer for high-efficiency separation and moderate capacity.