Nano‐Ruby: A Promising Fluorescent Probe for Background‐Free Cellular Imaging

Abstract

Bioprobes based on fluorescent ruby nanoparticles, which are suitable for ultrasensitive imaging, are reported. A stable aqueous/buffer colloid, permitting facile conjugation to proteins, is produced by femtosecond laser ablation of ruby and the nanoparticles (mean size 17 nm) are photostable, with long lifetime (1–4 ms) 694 nm emission. With time‐gating complete (>20 dB) suppression of cell autofluorescence and suppression of exogenous fluorophores is observed. Nanoparticles are imaged in as‐grown cells and those immunolabeled with quantum dots. Immunoassay binding to target biomolecules is also demonstrated.

Carbon‐Dot‐Decorated Nanodiamonds

“…Blinking and toxicity of quantum dots motivate investigation of alternative materials. Alternative inorganic fluorescent nanocrystals include group IV nanoparticles (silicon, silicon‐carbide, diamond, and germanium), core–shell fluorescent silica nanoparticles, lanthanide‐doped oxide, and other oxide nanoparticles . Photoluminescent (PL) metal nanoparticles and clusters (Au, Ag, Cu, Pt, and others) have also been fabricated recently …”

Fluorescence lifetime imaging (FLIM): Basic concepts and some recent developments

“…Today, fluorescence sensing and microscopy can be performed by labelling a sample with fluorescent dyes, fluorescent proteins, quantum dots (Resch-Genger et al, 2008) or other nanoparticles (Green et al, 2009;Howes et al, 2010Howes et al, , 2014, including nanodiamonds (Faklaris et al, 2009;Kuo et al, 2013;Mohan et al, 2010;Neugart et al, 2007) and nano-ruby (Edmonds et al, 2013), as reviewed recently , as well as imaging intrinsically fluorescent molecules naturally occurring within the sample -autofluorescence. In addition to fluorescence dyes, quantum dots and other nanoparticles have also recently found favour in cell imaging applications due to their high fluorescence quantum yield, low photobleaching susceptibility and narrow, size-dependent emission spectra which can be excited with a single wavelength (Grecco et al, 2004;Green, 2004;Howes et al, 2010;Michalet et al, 2005;Resch-Genger et al, 2008).…”

Glass and Process Development for the Next Generation of Optical Fibers: A Review

“…The ever-advancing synthetic techniques of NCs using a wide range of techniques such as wet chemistry [72][73][74], laser ablation [75], ball milling [58,59] and detonation [60] have shown exceptional control over emitting center concentration, crystallite phase, size, shape, composition and nanostructure. The technique, which consists of the synthesis of the NCs and then of their addition in the glass, gives a clear advantage as compared to the glass-ceramic technique for the synthesis of hybrid material, as with this novel fabrication technique, one can control the composition and nanostructure of the as-prepared NCs and glasses, overcoming the limitation of the glass ceramics method.…”