Search results for " recognition"
showing 10 items of 3220 documents
Host–Guest Interactions of Sodiumsulfonatomethyleneresorcinarene and Quaternary Ammonium Halides: An Experimental–Computational Analysis of the Guest…
2020
The molecular recognition of nine quaternary alkyl- and aryl-ammonium halides (Bn) by two different receptors, Calkyl-tetrasodiumsulfonatomethyleneresorcinarene (An), were studied in solution using...
Bringing a Molecular Plus One: Synergistic Binding Creates Guest-Mediated Three-Component Complexes
2020
Cethyl-2-methylresorcinarene (A), pyridine (B), and a set of 10 carboxylic acids (Cn) associate to form A·B·Cn ternary assemblies with 1:1:1 stoichiometry, representing a useful class of ternary systems where the guest mediates complex formation between the host and a third component. Although individually weak in solution, the combined strength of the multiple noncovalent interactions organizes the complexes even in a highly hydrogen-bond competing methanol solution, as explored by both experimental and computational methods. The interactions between A·B and Cn are dependent on the pKa values of carboxylic acids. The weak interactions between A and C further reinforce the interactions betw…
Label-Free Detection of Protein-Ligand Interactions by the Quartz Crystal Microbalance
2005
In recent years the quartz crystal microbalance (QCM) has been accepted as a powerful technique to monitor adsorption processes at interfaces in different chemical and biological research areas. In the last decade, the investigation of adsorption of biomolecules on functionalized surfaces turned out to be one of the paramount applications of the QCM comprising the interaction of nucleic acids, specific molecular recognition of protein-receptor couples, and antigen-antibody reactions realized in immunosensors. The advantage of the QCM technique is that it allows for a label free detection of molecules. This is a result of the fact that the frequency response of the quartz resonator is propor…
Water-compatible molecularly imprinted polymers obtained via high-throughput synthesis and experimental design.
2003
A technique allowing high-throughput synthesis and evaluation of molecularly imprinted polymer sorbents at a reduced scale (mini-MIPs) was developed and used for the optimization of MIPs for use in pure aqueous environments. The technique incorporated a 4-port liquid-handling robot for the rapid dispensing of monomers, templates, solvents and initiator into the reaction vessels of a 96-well plate. A library of 80 polymers, each ca. 50 mg, could thus be prepared in 24 h. The MIP rebinding capacity and selectivity could be rapidly assessed in the batch mode by quantifying nonbound fractions in parallel using a UV monochromator plate reader. This allowed a complete evaluation of the binding ch…
Molecular Recognition-Induced Function and Competitive Replacement by Hydrogen-Bonding Interactions: Amphiphilic Barbituric Acid Derivatives, 2,4,6-…
1998
The phenomenon of molecular recognition inducing further function is common in nature. However, there are few synthetic systems which achieve this cascade type mechanism, and those are generally ca...
Noncovalent molecular imprinting: antibody-like molecular recognition in polymeric network materials
1997
Abstract Molecular imprinting techniques allow the preparation of polymeric receptors which bind small molecules with affinities and selectivities of the same order as those observed in the binding of antigens by antibodies. The molecular imprinting technology has now reached a stage where the commercial use of imprinted materials is being assessed, notably for separations requiring strong and selective binding of small molecules. This development is driven by the potential advantages of polymeric receptors over biological in terms of stability, capacity, cost and ease of preparation. In this short review the state of the art of noncovalent imprinting is summarised indicating a few areas in…
Supramolecular chirality in organogels: a detailed spectroscopic, morphological, and rheological investigation of gels (and xerogels) derived from al…
2010
This Article addresses the formation of chiral supramolecular structures in the organogels derived from chiral organogelator 1R (or 2R), and its mixtures with its enantiomer (1S) and achiral analogue 3 by extensive circular dichroism (CD) spectroscopic measurements. Morphological analysis by atomic force microscopy (AFM) and scanning electron microscopy (SEM) were complemented by the measurements of their bulk properties by thermal stability and rheological studies. Specific molecular recognition events (1/3 vs 2/3) and solvent effects (isooctane vs dodecane) were found to be critical in the formation of chiral aggregates. Theoretical studies were also carried out to understand the interact…
Chiral recognition of protected amino acids by means of fluorescent binary complex pyrene/heptakis-(6-amino)-(6-deoxy)-β-cyclodextrin
2006
The ability of the binary complex pyrene (Py)/heptakis-(6-amino)-(6-deoxy)-β-cyclodextrin (am-β-CD) to act as a chiral selector was tested at two pH values (8.0 and 9.0). Phenylalanine (Phe), methionine (Met) and histidine (His) were used as chiral model molecules. The stability of ternary complexes Py/am-β-CD/amino acid was determined by means of spectrofluorimetric measurements. The data collected showed an increase in stability going from the binary to ternary complex and above all the possibility to use the binary complex as a chiral selector. Finally, data collected at two pH values showed that the binary complex is a better chiral selector when charged rather than in its neutral form.
Quantum dot/cyclodextrin supramolecular systems based on efficient molecular recognition and their use for sensing.
2011
A supramolecular system based on ketoprofen functionalised CdSe/ZnS nanoparticles and pyrene-modified β-CD was prepared and successfully used for molecular sensing of different analytes. In addition, a strategy for the individual recovery of all the components of the sensing assay is reported.
Noncovalent Saccharide Recognition by Means of a Tetrakis(bile acid)-Porphyrin Conjugate: Selectivity, Cooperation, and Stability
2010
Molecular recognition of Glu, Glc 2 -Glc 6 and Mal 3 by a tetrakis(bile acid)―porphyrin conjugate has been studied by using ESI-FTICR mass spectrometry. The bile acid conjugate was observed to form 1:1 noncovalent complexes with saccharides. The conjugate was found to have size-selectivity towards saccharides with three or more glucose residues. The Glc 3 and Glc 4 also formed kinetically the most stable complexes. The electron capture dissociation (ECD) experiments revealed that in complexation of an oligosaccharide three glucose residues interact with the bile acid conjugate, whereas additional glucose residues are susceptible to fragmentation. The ECD results also showed the significance…