Near-Infrared-Fluorescence-Enhanced Molecular Imaging of Live Cells on Gold Substrates

摘要

Biological imaging in the near-infrared (NIR) region has the advantages of deep photon penetration as a result of the relatively high transparency, reduced scattering, and low autofluorescence of biological tissues in the 0.8 to 1.4 μm range. Organic dyes, quantum dots, and single-walled carbon nanotubes (SWNTs) have been employed for in vitro and in vivo biological imaging in the NIR region. SWNTs are a group of one-dimensional (1D) macromolecular fluorophores with intrinsic bandgap fluorescence emission between 0.9 and 1.4 μm upon excitation in the visible or NIR region. The large Stokes shift makes SWNTs ideal probes for biological imaging with high contrast and low background. Thus far, SWNTs have been used as fluorescence tags for in vitro cell imaging, ex vivo imaging of tissues and organs, and in vivo imaging of normal organs as well as tumors.