Saccharide sensing

T.D. James, K.R.A.S. Sandanayake, S. Shinkai, Saccharide sensing with molecular receptors based on boronic acid , Angew. Chem, Int. Ed. EngL 1996, 35, 1910-1922. 

Figure 10.8 Two-component saccharide-sensing system using boronic acid receptor. Reprinted with permission from Ref. 170. Copyright 2006 American Chemical Society.

Aslan, K., Jian, Z., Lakowicz, J.R., Geddes, C.D., 2004. Saccharide sensing using gold and silver nanoparticles—a review. J. Fluoresc. 14 (4), 391. 

K. Sandanayake, S. Shinkai, Novel molecular sensors for saccharides based on the interaction of boronic acid and amines - saccharide sensing in neutral water, Journal of the Chemical Society-Chemical Communications 1994, 1083. 

While porphyrins can act as stand-alone receptors, functionalization with specific binding moieties is typically required in order to obtain selectivity for a chosen target. For example, in Seiji Shinkai s saccharide sensing systems, porphyrin scaffolds provide the chromogenic components... 

Koumoto demonstrated that azobenzene derivatives bearing one or two aminomethylphenylboronic acid groups 32 and 33 can be used for practical colorimetric saccharide sensing in neutral aqueous media. The observed stability constants (ATohs) for 33 were 433 for D-fructose and 13.0 M for o-glucose in 1 1 (v/v) methanol/water at pH 7.5 (phosphate buffer). 

For the community of supramolecular chemists, however, the sensor-analyte assemblies that display defined complex stoichiometry are more important. An excellent example of important electroneutral guests successfully addressed by fluorescence-based PET sensors are sugars, and saccharide sensing by boronic acids is a major success story of supramolecular chemists. Figure 17 shows two examples of PET-based saccharide sensors. 

Boronic Acid-Based Thin Films for Colorimetric Saccharide Sensing... 

This chapter summarizes research carried out at University of California, Santa Cruz to develop a non-enzymatic, optical approach to continuous saccharide sensing. It is based on the coupling of a fluorophore with analyte binding quencher. This review follows the progress of our research in the saccharide sensing field over the past 17 years. The review is organized into five parts (Sections 5.2-5.6). 

As a result of this dissociation, nonradiative deactivation pathways are removed, leading to a relative increase in fluorescence with increasing sugar concentration. A general mechanism that accounts for both fluorescence quenching and saccharide sensing is depicted in Scheme 5.3. 

Figure 5.15 Anionic dyes used in saccharide sensing. All compounds are shown as purchased or prepared. MPTS = methoxypyrenetrisulfonic acid, trisulfonate PTCA = perylenetetracarboxylic acid, tetracarboxylate HPTS = hydroxypyrenetrisulfonic acid, trisulfonate APTS = amino-pyrenetrisulfonic acid, trisulfonate fluorescein-SA = fluorescein-5-(and-6-)sulfonic acid lucifer yellow-I = lucifer yellow iodoacetamide SR-B = sulforhodamine-B HPTS(Lys)3 = hydroxypyrenetri(lysine) sulfonamide TCPP = tetrakis(4-carboxyphenyl)porphine TSPP = tetrakis(4-sulfophenyl)porphine.

It should be noted that carbohydrate recognition through formation of boronates has been remarkably successful. However, it involves covalent bonds and cannot be seen as biomimetic. For reviews, see James, T. D., Sandanayake, K. R. A. S. and Shinkai, S. (1996) Saccharide sensing with molecular receptors based on boronic acid, Angew. Chem., Int. Ed. Engl. 35, 1911-1922 Smith, B. D. (1996) Liquid membrane transport using boronic acid carriers, Supramolecular Chemistry 7, 55-60. 

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