Nucleic Acids Res. 2004 Jul 6;32(12):e95 doi:10.1093/nar/gnh096

Doi N, Kumadaki S, Oishi Y, Matsumura N, Yanagawa H.

In vitro selection of restriction endonucleases by in vitro compartmentalization.

The cleaved DNA molecules are selected by filling of their ends with biotin-dUTP