Further study on the two-column plasma catecholamine assay.

The two-column procedure for plasma catecholamine determination was adopted as a routine diagnostic test. It was found that the recovery of catecholamine added to properly preserved plasma was 65%. The most efficient recovery occurred when the water content of alumina used was above 23%. Both interassay and intra-assay precision were +/- 10% (coefficient of variation). The catecholamine was stable, in properly preserved plasma, for at least 18 days at -20 degrees C.