Immulon 1B exhibits a consistent medium binding affinity to proteins and complexes primarily with hydrophobic tendencies. Immulon 2HB has been irradiated to provide increased binding affinity for proteins and complexes primarily with hydrophilic tendencies. Immulon 4HBX is made of a different irradiated resin and has been developed to offer maximum protein uptake. Holders for flat-bottom strips available separately.