Nanoparticles doped

The synthesis can easily be modulated to obtain coated nanoparticles, doped nanoparticles, mixed nanoparticles, or onion nanoparticles [207-211]. 

The photoluminescence of these nanoparticles has very different causes, depending on the type of nanomaterial semiconductor QDs luminescence by recombination of excitons, rare-earth doped nanoparticles photoluminescence by atom orbital (AO) transitions within the rare-earth ions acting as luminescent centers, and metallic nanoparticles emit light by various mechanisms. Consequently, the optical properties of luminescent nanoparticles can be very different, depending on the material they consist of. 

The fast, sensitive, reliable, and reproducible detection of (bio)molecules including quantification as well as biomolecule localization, the measurement of their interplay with one another or with other species, and the assessment of biomolecule function in bioassays as well as in vitro and in vivo plays an ever increasing role in the life sciences. The vast majority of applications exploit extrinsic fluorophores like organic dyes, fluorescent proteins, and also increasingly QDs, as the number of bright intrinsic fluorophores emitting in the visible and NIR is limited. In the near future, the use of fluorophore-doped nanoparticles is also expected to constantly increase, with their applicability in vivo being closely linked to the intensively discussed issue of size-related nanotoxicity [88]. 

To overcome photobleaching and the low signal intensities of cyanine dyes Cy3 and Cy5, these dyes were encapsulated in silica coreshell nanoparticles [76]. The obtained dye-doped nanoparticles were applied in the DNA microarray-based... 

Traditionally, the sol-gel process has been used for the preparation of silica nanoparticles via the hydrolysis of alkoxides in organic solvents [52,53]. Similar hydrolysis and condensation carried out in w/o microemulsion offers robust control over the synthesis process. W/o emiflsion-mediated sol-gel synthesis is currently used for the fabrication of pure sihca, as well as inorganic and organic dye-doped silica nanoparticles. The synthesis of sihca and dye-doped nanoparticles is classified in the following sections on the basis of the classification of the head group fimctionahty of the major surfactant used. 

Lian W, Litherland SA, Badrane H, Tan WH, Wu DH, Baker HV, Gulig PA, Lim DV, Jin SG (2004) Ultrasensitive detection of biomolecifles with fluorescent dye-doped nanoparticles. Anal Biochem 334 135-144... 

Qian KJ, Zhang L, Yang ML, He PG, Fang YZ (2004) Preparation of luminol-doped nanoparticle and its application in DNA hybridization analysis. Chinese J Chem 22 702-707... 

In brief, the core-shell technique allows one to prepare doped nanoparticles that contain no other dopant sites than those known from the corresponding bulk material, despite their small size, below 15 nm. The quantum efficiency of lanthanide ions can also be improved by surface modification of the nanoparticles. 

Fig. 10.39. STM images of (a) a B-doped nanoparticle chain, (b) a B-doped straight nanowire, and (c) boron-induced reconstruction of SiNW [45].

T, Nutz and M, Haase, Wet-chemical synthesis of doped nanoparticles Optical properties of oxygen-deficient and antimony-doped colloidal Sn02. J. Phys. Chem. B, 104 8430-8437, 2000... 

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