(127c) Single-Walled Carbon Nanotube Labels and Optical Sensors in Live Cells
- Conference: AIChE Annual Meeting
- Year: 2005
- Proceeding: 2005 Annual Meeting
- Group: Biomedical Applications of Nanotechnology (Bionanotechnology)
- Time: Monday, October 31, 2005 - 3:55pm-4:15pm
Complexes of DNA and single-walled carbon nanotubes (SWNT) exhibit long-lived, modifiable near-infrared fluorescence emission which was used to fabricate long-term labels and optical sensors within cells and tissues. Nanotube fluorescence is in the near-infrared region and does not photobleach under prolonged excitation, permitting continuous monitoring through biological media for experiments lasting several hours.
The transition of the DNA secondary structure from the B to Z conformation was detected via modulation of the intrinsic near-infrared fluorescence of SWNT. A reversible shift in emission energy of DNA-encapsulated nanotubes was found to closely match the thermodynamics of the transition of unbound DNA.
DNA-nanotube complexes were taken into endosomes, situated near the cell nucleus, and remained visible after multiple cell divisions. The sensors demonstrated optical detection of the DNA B-Z transition within mammalian cells, muscle tissue and whole blood.