Selective retention of non-ortho substituted coplanar chlorinated biphenyl congeners on adsorbents for column chromatography

Abstract

By adsorption chromatography on basic alumina, the non-ortho substituted coplanar chlorinated biphenyl (CB) congeners CB-37, CB-81, CB-77, CB-126, and CB-169 were found to be selectively retained when a mixture of 34 CB congeners was eluted by n-hexane. CB-77, CB-126 and 169 show dioxin-like biological activity/toxicity, and are the most toxic CB congeners. The less toxic monortho and di-ortho substituted coplanar CB congeners were not retained to the same degree. On acidic and neutral alumina, the elution patterns were similar to the patterns observed on basic alumina. Florisil did also show elution patterns similar to the basic alumina, while silica was found to be nonselective. The mechanism of retention of non-ortho substituted CB congeners on alumina is discussed.