By the 1990s, with the development of molecular biology and molecular evolution in vitro, Breaker and his colleagues firstly obtained DNA molecule with cleaving RNA activity depending on Pb2+ ion, and denominated DNAzyme.

• 进入20世纪90年代，随着分子生物学和体外分子进化技术进一步发展，Joyce和Breaker等[3]人通过体外筛选方法首次得到了依赖于Pb2+具有切割RNA分子功能的DNA分子，并将其命名为DNA enzyme。