为什么我的EcoRI酶切总拖带...

Enzyme looks fine as digestion in lane 1 shows no smears, signals above the band could be trace amount of contaminants. The plasmid DNA used in lane 2 could be sensitive to EcoR I, or the preparation of this plasmid DNA may be damaged.

ECORI，有时候会有星活性，你可以看看你的酶，NEB的酶不是HF的是有星活性的