A naphthoquinone adsorbent for affinity chromatography of human dihydropteridine reductase.

1. A 1,2-naphthoquinone adsorbent is described which allows simple purification of dihydropteridine reductase directly from crude extract. 2. The native molecular weight indicates that a tetramer structure of the species is isolated by this method; this is unusual and possibly reflects the capacity of the procedure to preserve the native state of the enzyme.