Sensing, luminescence

Figure 2. Principles of reversible luminescence sensing using photochemical quenching processes (electron, energy or proton transfer). Dye = luminescent indicator Q = quencher species dotted arrow non-radiative deactivation processes. The luminescence intensity (and excited state lifetime) of the indicator dye decreases in the presence of the quencher. The indicator dye is typically supported onto a polymer material in contact with the sample. The quencher may he the analyte itself or a third partner species that interacts with the analyte (see text).

The scientists from Hong Kong reported83 on a sol-gel derived molecular imprinted polymers (MIPs) based luminescent sensing material that made use of a photoinduced electron transfer (PET) mechanism for a sensing of a non-fluorescent herbicide - 2,4-dichlorophenoxyacetic acid. A new organosilane, 3 - [N,V-bis(9-anthrylmethyl)amino]propyltriethoxysilane, was synthesized and use as the PET sensor monomer. The sensing MIPs material was fabricated by a conventional sol-gel process. 

Beer PD, Timoshenko V, Maestri M et al (1999) Anion recognition and luminescent sensing by new ruthenium(II) and rhenium(I) bipyridyl calix[4]diquinone receptors. Chem Commun... 

Borisov SM, Krause C, Arain S, Wolfbeis OS (2006) Simultaneous and contactless luminescent sensing and imaging of oxygen and carbon dioxide. Adv Mater 18 1511-1516... 

The goal of luminescent sensing is perhaps to implement methods and instrumentation capable of performing simple, accurate, and precise measurements in real time. These qualities of sensing systems are especially desirable in the biomedical field in which relevant physiological parameters may change constantly during time expands from a fraction of a second to several hours. 

Luminescence sensing was used for anion recognition [49,117,118]. Beer et al. [117] reported the use of a modified 2,2 -bipyridine ligand bonded to Re(CO)3Cl [see Fig. 26 A]. The modified bipyridine ligand contained a macrocyclic (NH)4 cavity capped with a calix [4]arene strapped on its back. The cavity was of sufficient size to accommodate anions. An increase in emis-... 

Cation recognition by luminescence sensing has also been reported. As referred to above, release and recapture of alkali and alkaline earth metal ions for [(bpy)Re(CO)3L ]+, where Lj contains an azacrown ether [63] was controlled by light. A sensor for lanthanide ions is shown in Fig. 27. The photoactive center was RcI( bpy ) and its emission was quenched by the lanthanide ion [119]. 

Wolfbeis OS, Durkop A, Wu M, Lin Z. A Europium-ion-based luminescent sensing probe for hydrogen peroxide. Angewandte Chemie, International Edition 2002, 41, 4495 1498. 

Southard GE, Van Houten KA, Ott EW Jr, Murray GM. Luminescent sensing of orga-nophosphates using europium(III) containing imprinted polymers prepared by RAFT polymerization. Anal Chim Acta 2007 581 202-7. 

Shao, N., Jin, J., Wang, G, et al. (2008) Europium(lll) complex-based luminescent sensing probes for multi-phosphate anions modulating selectivity by ligand choice. Chemical Communications, 1127-1129. 

Figure 13.15 Schematic representation of synthesis and surface modification of nanoparticles [54]. (Reproduced with permission from W.J. Rieter et al., Surface modification and functionalization of nanoscale metal-organic frameworks for controlled release and luminescence sensing, Journal of the American Chemical Society, 129, 9852-9853, 2007. 2007 American Chemical Society.)...

Gunnlaugsson, T., Harte, A.J., Leonard, J.R, and Nieuwenhuyzen, M. (2002) Delayed lanthanide luminescence sensing of aromatic carboxylates using heptadentate triamide Tb(III) cyclen complexes the recognition of salicylic acid in water. Chemical Communications, 2134-2135. 

Luminescence Sensing Some luminescent compounds can serve as probes of analytes such as metal ions. Upon coordination with a metal ion, the luminescence of a ligand may be enhanced, quenched, or shifted in color (the wavelength of maximum intensity). In addition, changes in the solution conditions (pH, ionic strength, temperature or the presence of macromolecular hosts capable of forming organized structures) often affect luminescence properties. 

Simpson ML, Sayler GS, Patterson G, Nivens DE, Bolton E, Rochelle J, Amott C, Applegate B, Ripp S, Guillom MA. An integrated CMOS microluminometer for low-level luminescence sensing in the bioluminescent bioreporter integrated circuit. Sens Actuators B 2001 72 135-41. 

CaUan JE, De Silva AP, Mulrooney RC, McCaughan B (2007) Luminescent sensing with quantum dots. J Incl Phenom Macrocycl Chem 58 257-262... 

This chapter does not cover the use of metal ions as allosteric effectors (3), skeletal components (4) (see Crystal Engineering, Supramolecular Materials Chemistry), or sensing elements (5) (see Molecular Redox Sensors, Colorimetric Sensors and Luminescent Sensing, Supramolecular Devices). It also does not address the interaction of metal complexes with biological systems (see Synthetic Peptide-Based Receptors, Biological Small Molecules as Receptors, Molecular Recognition and Supramolecular Bioinorganic Chemistry, Supramolecular Aspects... 

The area of luminescence sensing has been central to the development of supramolecular chemistry. Encompassing... 

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