Intermolecular interactions recognition

Altschuh D, Oncul S, Demchenko AP (2006) Fluorescence sensing of intermolecular interactions and development of direct molecular biosensors. J Mol Recognit 19 459 477... 

Molecular imprinting can be accomplished in two ways (a), the self assembly approach and (b), the preorganisation approach3. The first involves host guest complexes produced from weak intermolecular interactions (such as ionic or hydrophobic interaction, hydrogen bonding) between the analyte molecule and the functional monomers. The self assembled complexes are spontaneously formed in the liquid phase and are sterically fixed by polymerisation. After extraction of the analyte, vacant recognition sites specific for the imprint are established. Monomers used for self assembly are methacrylic acid, vinylpyridine and dimethylamino methacrylate. 

Noncovalent interactions play a key role in biodisciplines. A celebrated example is the secondary structure of proteins. The 20 natural amino acids are each characterized by different structures with more or less acidic or basic, hydrophilic or hydrophobic functionalities and thus capable of different intermolecular interactions. Due to the formation of hydrogen bonds between nearby C=0 and N-H groups, protein polypeptide backbones can be twisted into a-helixes, even in the gas phase in the absence of any solvent." A protein function is determined more directly by its three-dimensional structure and dynamics than by its sequence of amino acids. Three-dimensional structures are strongly influenced by weak non-covalent interactions between side functionalities, but the central importance of these weak interactions is by no means limited to structural effects. Life relies on biological specificity, which arises from the fact that individual biomolecules communicate through non-covalent interactions." " Molecular and chiral recognition rely on... 

Although the chiral recognition factor in such systems is relatively weak, there is no question that it is measurable and provides a useful approach to elucidating intermolecular interactions between nonreacting molecules. 

Besides, information on intermolecular interactions has been derived in these studies from complexation-induced shifts (CIS). The chemical shift is an indicator for the shielding of a nucleus and thus for the electronic state of a specific proton. Since the electronic environment may change on complexation, CIS can be used to monitor where host-guest contacts may take place. If these interactions occur stereoselectively, the CIS will be different for the two guest enantiomers (AS distinct from 0) giving possibly some insight into the chiral recognition mechanism. 

As the electrostatic potential is of importance in the study of intermolecular interactions, it has received considerable attention during the past two decades (see, e.g., articles on the molecular potential of biomolecules in Politzer and Truhlar 1981). It plays a key role in the process of molecular recognition, including drug-receptor interactions, and is an important function in the evaluation of the lattice energy, not only of ionic crystals. 

Hunter, C.A. (2004) Quantifying intermolecular interactions Guidelines for the molecular recognition toolbox. Angew. Chem., Int. Ed., 43, 5310-5324. 

Supermolecules built from small molecules mainly involve intermolecular interactions. On the other hand, with macromolecules the supramolecular association may be either intermolecular, occurring between the large molecules, or intramolecular involving recognition sites located either in the main chain or in side-chain appendages, thus leading to chain folding and structuration of the macromolecular... 

Intramolecular and intermolecular interactions between C—H groups and the 71 system135 of carbon double bonds of olefins and of aromatic rings are of interest in the fields of molecular recognition and inclusion complexes in both organic chemistry and biochemistry. 

---