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Efficient extraction and detection of aromatic toxicants from crude oil and tar balls using multiple cyclodextrin derivatives

“…The most likely explanation for this scenario is that cyclodextrins facilitate the association of the aromatic toxicants with fluorophore 4. This facilitated association can either occur via the formation of a ternary complex in the cyclodextrin cavity (as has been demonstrated for γ -cyclodextrin [20][21][22]44,45 and 2-HPCD 46 , 47 ), or via association of one of the two energy transfer partners outside the cyclodextrin cavity (a more likely scenario for the smaller cyclodextrin derivatives).…”

Enantioselective room temperature phosphorescence detection of non-phosphorescent analytes based on interaction with β-cyclodextrin/1-bromonaphthalene complexes

“…Based on the formation of such ternary complexes, also various bromonaphtol derivatives have been detected by RTP under non-deoxygenated conditions [7,8]. Nazarov et al have even reported strong signals for an organic phosphorophore not substituted with a heavy atom such as bromine: for naphthalene-␤-CD-adamantane suspensions a phosphorescence lifetime as long as 10.3 s could be obtained [9].…”

Long-lived phosphorescence of arenes in complexes with cyclodextrins 2. Room-temperature phosphorescence of ternary complexes of naphthalene and phenanthrene with β-cyclodextrin and adamantane derivatives in the presence of oxygen

“…The use of urotropin (solid, under normal conditions, and well soluble in water compound with a cage structure similar to that of Ad) as the third component causes no aggregation and appearance of RTP at all. 1 In contrast to this, with Ad as the third component of the complex both aggregates and light scattering are retained in the sample at 50 °C. Therefore, preferred use of solid (at room tem perature) hydrocarbons becomes understandable.…”

“…For instance, in our previous study 1 we first showed that in a molecularly organized system based on aggre gated ternary complex naphthalene d 8 -β cyclodextrin (β CD)-adamantane (Ad) the probe molecule of naph thalene d 8 exhibits long lived room temperature phos phorescence (RTP) with a lifetime, τ, of 10.3 s in the presence of molecular oxygen (major quencher of phos phorescence under normal conditions). Removal of oxy gen from the sample results in an increase in τ to 15.5 s. This means that in the aggregates formed the naphtha lene d 8 molecule is reliably isolated from oxygen and in tra aggregate oxygen diffusion is essentially hindered.…”

“…The phosphorescence lifetimes were measured on a setup re ported elsewhere. 1 Quantum chemical calculations. Semiempirical quantum chemical calculations of substrate molecules (naphthalene d 8 , phenanthrene, fluorene, Ad, DMAD, DA and DAD) and their 1 : 1 and ternary inclusion complexes with β CD were carried out by the MNDO/PM3 (from this point on, PM3) method with standard parametrization 9 using the PC GAMESS 99 pro gram package.…”