Complexes bioprobes

Elhabiri et al., 2004a). The ultimate fixation of the third ligand in the neutral helicate [f 2(L13%] induces a considerable entropic gain to the overall complexation process, which is responsible for both extreme thermodynamic stability (Elhabiri et al., 1999) and kinetic inertness (Elhabiri et al., 2004b, Figure 59), which make these helicates promising building blocks for the development of luminescent bioprobes (see Section 6). 

The structural studies by X-ray diffraction and NMR have been complemented by a high-resolution luminescence analysis of the Eu "-containing complexes similar to the one conducted for the homometallic bioprobes (Section 6.3.1). Data are collected in Table 24. Firstly, the energy of the Dq —> transition calculated with Eq. (19) (see Section 3.5) and the... 

In a very general sense, Stephenson has defined the term bioprobes as. functional molecules or devices that provide information about biological systems. The high kinetic and thermodynamic stability of many organo-metallic complexes, in addition to their electronic and spectroscopic properties, have spurred their use in numerous sensor applications. Among those are sensors which involve biomolecules, or which detect biomolecules. In this chapter, only a few selected examples are presented as an introduction to the field. Organometallic biosensors are comprehensively summarized in four chapters in a recent book on bioorganometallic chemistry. A more... 

A new polynuclear dendritic structure (Sm -G3P-2,3-naphthalimide) exhibits, upon a single excitation wavelength, two types of emission in the visible and in the near-infrared (NIR) ranges. The Sm macro-molecular complex can operate as a bioprobe suitable for microscopy in living cells, emitting both visible and NIR light. 

The metalloenzymes and modeling area is still very open, and it is now clear that certain complexes will play a role in the energy transition that is currently underway. In addition, organometallic bioprobes, connected or not with therag-nosis, represent a vast area needing only to be developed. The lines of force, the promises, and directions of travel in the field are laid out before us here. It is hoped that the reader will envisage others, guided, inspired and stimulated by the work presented in this volume. 

Principal Component Analysis (PCA) has proved a powerful statistical method to distiguish the contributions of multiple effects on a particular complex. The data for tricarbonyl(cyclohexadiene)iron (5) produces the PCA plot shown in Fig. 7.7d, in which values for pure solvents lie at the corners, data for binary mixtures, define the edges, and three-solvent mixtures give points that lie inside the boundaries [45]. Although so far demonstrated for single complexes and up to three solvents, the combination of data from two differentially responding complexes (see Fig. 7.7c) in a multi-carbonylmetal approach should give exceptionally clear measures of properties of hydrophobic and hydrophilic environments when exploited in bioprobe applications. 

The chromophore is directly coordinated to the lanthanide ion (see Figure 10a). Chromophores are thus designed to ensure an efficient positioning of the triplet energy, which would allow the photosensitization of the lanthanide ion, and enclose adequate coordination sites to guarantee a stable complexation of the cation. For further details, Lanthanides Luminescence Applications and Luminescent Bioprobes. 

Some examples are emphasized in the next chapter Lanthanides Luminescence Applications). The luminescence spectra of various lanthanide ions will be given and several applications using luminescent lanthanide complexes will be presented. Luminescent Bioprobes, some practical data and a case of study will be presented. The properties of a series of lanthanide complexes (i.e., with ligands that share a common architectme) will be expUcated both from a physicochemical and from a photophysical point of view. It will be demonstrated that these complexes are highly stable and present interesting photophysical properties, so that their application as bioprobe can be imdertaken. 

Carboxylate Lanthanide Complexes with Multi-dentate Ligands Lanthanides Luminescence Applications Lanthanides in Living Systems Luminescence Luminescent Bioprobes Metal-Organic Frameworks Molecular Magnetic Materials Near-Infrared Materials. 

The first step before interacting with cells consists in determining the nontoxicity of the complex. The WST-1 proliferation assay is widely used for this purpose WST-1 dye (slightly red) is converted into a dark red formazan compound on enzymatic modification this will occur only if cells are alive. The assay is performed after incubation with increasing amounts of the complex to be tested. Cell viability will be tested by the same way, over a period of incubation of more than 24 h. Such an essay has been performed with [Ln2(L )3] complexes and without any effect up to concentrations of 500 J,M. There is no toxicity of the complexes toward cells, which can be expressed as following the half maximal inhibitory concentration /C50 is more than 500 qM. This can be compared to some cyclen-based bioprobes for which /C50 values are around 200 J,M. 

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