Color-Switchable Nanosilicon Fluorescent Probes

• Fluorescent probes are vital to cell imaging by allowing specific parts of cells to be visualized and quantified. Color-switchable probes (CSPs), with tunable emission wavelength upon contact with specific targets, are particularly powerful because they not only eliminate the need to wash away all unbound probe but also allow for internal controls of probe concentrations, thereby facilitating quantification. Several such CSPs exist and have proven very useful, but not for all key cellular targets. Here we report a pioneering CSP for in situ cell imaging using aldehyde-functionalized silicon nanocrystals (SiNCs) that switch their intrinsic photoluminescence from red to blue quickly when interacting with amino acids in live cells. Though conventional probes often work better in cell-free extracts than in live cells, the SiNCs display the opposite behavior and function well and fast in universal cell lines at 37 °C while requiring much higher temperature in extracts. Furthermore, the SiNCs only disperse in cytoplasm not nucleus, and their fluorescence intensity correlated linearly with the concentration of fed amino acids. We believe these nanosilicon probes will be promising tools to visualize distribution of amino acids and potentially quantify amino acid related processes in live cells. 

Subject headings

NATURVETENSKAP  -- Biologi -- Cellbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Cell Biology (hsv//eng)

Keyword

bioimaging

color-switchable probe

nanocrystal

photoluminescence

silicon

surface chemistry

Amino acids

Cell culture

Cells

Color

Fluorescence

Nanocrystals

Probes

Silicon compounds

Amino-acids

Bio-imaging

Cell imaging

Fluorescent probes

Live cell

Nano-silicon

Silicon nanocrystals

Switchable

Tunable emissions

aldehyde

amino acid

fluorescent dye

nanoparticle

Aldehydes

Fluorescent Dyes

Nanoparticles

Publication and Content Type

ref (subject category)

art (subject category)