Nonfunctionalized PNAs as Beacons for Nucleic Acid Detection in a Nanopore System.

In this work, single-channel current recordings were used to selectively detect individual ssDNA strands in the vestibule of the α-hemolysin (α-HL) protein nanopore. The sensing mechanism was based on the detection of the intrinsic topological change of target ssDNA molecules after the hybridization with complementary PNA fragments. The readily distinguishable current signatures of PNA-DNA duplexes reversible association with the α-HL's vestibule, in terms of blockade amplitudes and kinetic features, allows specific detection of nucleic acid hybridization.