<ul><li><span style="font-size:10pt;"></span>Macroporous polystyrene beads</li> <li>Derivatized with iminodiacetic acid groups</li> <li>Affinity for heavy metal cations</li> </ul>
<ul><li>Macrporous polystyrene beads</li> <li>Derivatized with aminomethylphosphonic acid groups</li> <li>Affinity for polyvalent metal cations</li> </ul><p></p>