The objective of this research is to develop a novel near-field scanning probe with sub-diffraction-limit resolution by directly fabricating nanometer sized light source on the tip, and to use the probe to characterize the distribution of multi-stage combinatorial directed nanovectors in tissues and living cells for tumor characterization and destruction.

The expected light source size is 10-50 nm, an order of magnitude smaller than that of a current NSOM.  The research will likely open many exciting opportunities in biomedical and industrial applications including near-field microscopy of sub-cellular structures, direct material patterning, ultra high-density data storage, and compact light-on-chip biosensors and biochips. The emission wavelength of the probe will cover the spectrum from near-UV to the visible range with imaging resolutions well beyond the diffraction limit.  The concept of “Nano-LED at-tip” using silicon technology was originated in the Zhang Lab in 2006.  The technology has attracted increased attention from both MEMS and Nanodevice communities as well as from materials and medical imaging researchers around the world.  The preliminary studies using Nano-LEDs made of doped silicon oxide, or light emitting quantum dots on a probe tip integrated with conventional NSOM (in collaboration with Professor David Vanden Bout, UT Austin, Biochemistry), have shown great promise.  It was the first time that apertureless images have been acquired with a light source embedded in a scanning probe tip.