Inhibition of DNA transcription using cationic mixed monolayer protected gold clusters

Efficient recognition of DNA is a prerequisite for the development of biolo gical effectors, including transcription and translation regulators, transf ection vectors, and DNA sensors. To provide an effective scaffold for multi valent interactions with DNA, we have fabricated mixed monolayer protected gold clusters (MMPCs) functionalized with tetraalkylammonium ligands that c an interact with the DNA backbone via charge complementarity. Binding studi es indicate that the MMPCs and DNA form a charge-neutralized, nonaggregated assembly. The interactions controlling these assemblies are highly efficie nt, completely inhibiting transcription by T7 RNA polymerase in vitro.