Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Near-Infrared Fluorescence Enhanced (NIR-FE) Molecular Imaging of Live
  Cells on Gold Substrates   Low quantum yields of near infrared (NIR) fluorophores have limited their
capabilities as imaging probes in a transparent, low background imaging window.
Here for the first time we reported near-infrared fluorescence enhance (NIR-FE)
cell imaging using nanostructured Au substrate, which was employed as a general
platform for both single-walled carbon nanotubes (SWNTs) and organic
fluorescent labels in the NIR region. Fluorescence intensity, as well as cell
targeting specificity, was greatly improved by this novel imaging technique.
With NIR-FE imaging, we were able to image SWNT-stained cells at short exposure
time of 300ms, and push the detectable limit of SWNT staining of cells down to
an ultralow concentration of ~50 pM. Further, different degrees of fluorescence
enhancement for endocytosed, intracellular SWNTs vs. nanotubes on the cell
membrane at the cell/gold interface were observed, suggesting the possibility
of using this technique to track the transmembrane behavior of NIR
fluorophores.

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The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
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The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: quant-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
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The categories of this paper are: cs
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The categories of this paper are: ao-sci