Dye inclusion crystals

Dendrimers, p. 432 Drug Delivery, p. 484 Dye Inclusion Crystals, p. 497 Enzyme Mimics, p. 546 Glycoluvil-Based Hosts, p. 597 Hydrogen Bonding, p. 658 Hydrophobic Ejfects, p. 673... 

Sedarous. S. Subramony, J.A. Kahr. B. Stmcture and optical characterization of Rochelle salt dye inclusion crystals and the fluorescence detection of their phase transitions. Ferroelectrics 1997, 191. 302-306. 

Concepts in Crystal Engineering, p. 319 Crystal Engineering with Hydrogen Bonds, p. 357 Crystal Structure Prediction, p. 371 Cfystalline Microporous Silicas, p. 380 Dye Inclusion Crystals, p. 497 Hofmann-Type Clathrates, p. 645 Mineralomimetic Structures, p. 868 Molecular Squares, Boxes, and Cubes, p. 909 Organic Zeolites, p. 996 Soft/Smart Materials, p. 1302... 

In small pore zeolites with cage structure, e. g., faujasites, dye molecules encapsulated by in situ synthesis or crystallization inclusion are stable against extraction.1 2 However, these methods fail for MCM-41 due to the channel structure and the wider pore diameter (3 nm) of the host material. Covalent bonding of guests is necessary to obtain diffusion stability. Therefore, anchoring of organic molecules with catalytic functions into MCM-41 by covalent bonding was recently reported by Brunei et al.3... 

Pseudo-stilbenes may emit fluorescence that is, contrary to true stilbenes, generally weak at room temperature and often weak even at low temperatures. Protonated azobenzene-type molecules and many protonated azo dye molecules emit strong fluorescence in sulfuric acid at 77 K with quantum yields of about 0.1. Inclusion of azobenzene in the channels of AIPO4-5 crystals provides complexation of the n-electrons and space confinement. This leads to emission by protonated azobenzene at room temperature. For their cyclopalladated azobenzenes, Ghedini et al. " report quantum yields of ca. 1T0 and lifetimes of ca. 1 ns. In contrast, donor/acceptor pseudo-stilbenes, if emitting at low temperatures or when adsorbed to surfaces, are weak emitters. In textile chemistry, it has long been known that azo dyes adsorbed to fibers may show fluorescence. ... 

So far, only few studies have been reported on the use of porous zeolite films for optical applications. While significant efforts have been extended towards the encapsulation of various dye molecules into zeolite crystals or powders (see section 2.2), integration of such systems into thin films has not been pursued by many groups yet. As one of the few examples reported so far, we discuss the inclusion of oriented hemicyanine dyes into thin zeolite films aimed at Second Harmonic Generation (SHG).[106] The zeolite film plays the important role... 

It has been reported that y3-CD could improve the selectivity of the color reactions of various metal ions with triphenylmethane, xanthene acid dyes and some other coloring reagents. The effect of fi-CD on the association compound system of metal (Mo, Zn, Co)-thiocyanate basic dyes such as malachite green, crystal violet, rhodamine B, rhodamine 6G and butyhhodamine B, has been investigated and the result shows that /3-CD could contribute to a more sensitive and stable system which improve the solubility of the basic dyes and produce a favorable microenviromnent for the color reactions [63]. /3-CD could be employed to solubilize the 1,2-amino anthraquinone in water due to the formation of inclusion complex which acts as a ligand for metal ions could be used for the determination of palladium at trace levels by spectrophotometry. In the spectrophotometric determination of microamounts of Zn based on the Zn-dithizone color reaction, -CD could increase the apparent molar absorptivity at 538 nm by 8.37 times. In the presence of cr-CD, the determination sensitivity of copper in leaves based on the color reaction of Cu(II) and mesotetrakis (4-methoxy-3-sulfophenyl) porphyrin was enhanced by 50% in the spectrophotometric analysis [64,65]. 

It appears to be important for the sample to enter the crystal lattice of the matrix for satisfactory ion production to occur and proteins tagged with a dye have been used to demonstrate that inclusion does indeed take place. Under ideal conditions high sensitivity can be achieved some samples can be analyzed from as little as a few hundred attomoles applied... 

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