DNA oligonucleotide templated nanohybrids using electronic type sorted carbon nanotubes for light harvesting.

Light harvesting nanostructure hybrids have been designed and demonstrated using single-wall carbon nanotubes (SWCNTs) and porphyrin chromophores. DNA oligonucleotides are used to conjugate SWCNTs with light-absorbing chromophores for transparent films which generate photocurrents. High-purity semiconducting SWCNTs demonstrate significant enhancement in the photocurrent compared to metallic or unsorted tubes.

Optical nanosensor architecture for cell-signaling molecules using DNA aptamer-coated carbon nanotubes.

We report a novel optical biosensor platform using near-infrared fluorescent single-walled carbon nanotubes (SWNTs) functionalized with target-recognizing aptamer DNA for noninvasively detecting cell-signaling molecules in real time. Photoluminescence (PL) emission of aptamer-coated SWNTs is modulated upon selectively binding to target molecules, which is exploited to detect insulin using an insulin-binding aptamer (IBA) as a molecular recognition element. We find that nanotube PL quenches upon insulin recognition via a photoinduced charge transfer mechanism with a quenching rate of k(q) = 5.