The assay is based on the observation that complexes of protein and DNA migrate through a non-denaturing polyacrylamide gel more slowly than free DNA fragments or double-stranded oligonucleotides.

• 该检测观察的基础是：蛋白与DNA的复合体在非变性聚丙烯酰胺凝胶中的迁移速率大大低于DNA片段或双链寡核苷酸的迁移速率。