ProPac WCX-10 Guard 4X50MM. Use Thermo Scientific™ ProPac™ WCX-10 LC Columns to provide exceptionally high resolution for separations of proteins and their variants. Based on stationary phases composed of 10µm nonporous polymeric beads, ProPac columns resolve isoforms that differ by a single charged residue. A thin, hydrophilic layer grafted to the particle core eliminates unwanted secondary interactions. The cation-exchange surface provides pH-based selectivity control and fast mass transfer for high-efficiency separation and moderate capacity.