Journal of Inclusion Phenomena and Macrocyclic Chemistry 

About: Journal of Inclusion Phenomena and Macrocyclic Chemistry is an academic journal. The journal publishes majorly in the area(s): Cyclodextrin & Crystal structure. It has an ISSN identifier of 0923-0750. Over the lifetime, 4023 publications have been published receiving 50330 citations.

The Driving Forces in the Inclusion Complexation of Cyclodextrins

Abstract: The driving forces leading to the inclusion complexation of cyclodextrins were reviewed, which included the electrostatic interaction, van der Waalsinteraction, hydrophobic interaction, hydrogen bonding, release of conformational strain,exclusion of cavity-bound high-energy water, and charge–transferinteraction. It was shown that except for the release of conformation strain and exclusion of cavity-bound water, the otherinteractions were indeed contributive to the complex formation. However, it was concludedthat the enthalpy and entropy changes of the complexation were not good criteria to be used injudging whether a particular driving force was present or important, mainly because of theoccurrence of enthalpy-entropy compensation. On the other hand, the multivariate quantitativestructure-activity relationship analyses usually could illustrate which driving forces wereimportant in certain inclusion complexation systems.

A Practical Guide for the Determination of Binding Constants

Abstract: When working in the field ofhost–guest chemistry, the binding constants have to bedetermined on many occasions Here is a detaileddocument of how to determine the binding constantswhich covers both the basic principle and thepractical issue: a practical experimental guideline,a representative method for the determination ofstoichiometry and for the evaluation of a complexconcentration, precautions to be taken on setting upconcentration conditions of the titration experiment,practical data-treatment methods and estimation ofstatistical errors This document is described indetail using the basic level of mathematics,statistics, and programs of spreadsheet softwareEspecially, the titration experiments by means ofUV-visible and NMR spectroscopy are carried out anddescribed

Cyclodextrin based novel drug delivery systems

Abstract: The versatile pharmaceutical material cyclodextrin’s (CDs) are classified into hydrophilic, hydrophobic, and ionic derivatives. By the early 1950s the basic physicochemical characteristics of cyclodextrins had been discovered, since than their use is a practical and economical way to improve the physicochemical and pharmaceutical properties such as solubility, stability, and bioavailability of administered drug molecules. These CDs can serve as multi-functional drug carriers, through the formation of inclusion complex or the form of CD/drug conjugate and, thereby potentially serving as novel drug carriers. This contribution outlines applications and comparative benefits of use of cyclodextrins (CDs) and their derivatives in the design of novel delivery systems like liposomes, microspheres, microcapsules, nanoparticles, cyclodextrin grafted cellulosic fabric, hydrogels, nanosponges, beads, nanogels/nanoassemblies and cyclodextrin-containing polymers. The article also focuses on the ability of CDs to enhance the drug absorption across biological barriers, the ability to control the rate and time profiles of drug release, drug safety, drug stability, and the ability to deliver a drug to targeted site. The article highlight’s on needs, limitations and advantages of CD based delivery systems. CDs, because of their continuing ability to find several novel applications in drug delivery, are expected to solve many problems associated with the delivery of different novel drugs through different delivery routes.

Supramolecular chemistry — Scope and perspectives: Molecules — Supermolecules — Molecular devices

Abstract: Supramolecular chemistry is the chemistry of the intermolecular bond, covering the structures and functions of the entities formed by association of two or more chemical species Molecular recognition in the supermolecules formed by receptor-substrate binding rests on the principles of molecular complementarity, as found in spherical and tetrahedral recognition, linear recognition by co-receptors, metallo-receptors, amphilic receptors and anion coordination Supramolecular catalysis by receptors bearing reactive groups effects bond cleavage reactions as well as synthetic bond formation via co-catalysis Lipophilic receptor molecules act as selective carriers for various substrates and allow the setting up of coupled transport processes linked to electron and proton gradients or to light Whereas endo-receptors bind substrates in molecular cavities by convergent interactions, exo-receptors rely on interactions between the surfaces of the receptor and the substrate; thus new types of receptors such as the metallonucleates may be designed In combination with polymolecular assemblies, receptors, carriers and catalysts may lead to molecular and supramolecular devices, defined as structurally organized and functionally integrated chemical systems built on supramolecular architectures Their recognition, transfer and transformation features are analyzed specifically from the point of view of molecular devices that would operate via photons, electrons or ions, thus defining the fields of molecular photonics, electronics and ionics Introduction of photosensitive groups yields photoactive receptors for the design of light conversion and charge separation centres Redox active polyolefinic chains represent molecular wires for electron transfer through membranes Tubular mesophases formed by stacking of suitable macrocyclic receptors may lead to ion channels Molecular self-assembling occurs with acyclic ligands that form complexes with a double helical structure Such developments in molecular and supramolecular design and engineering open perspectives towards the realization of molecular photonic, electronic and ionic devices, that would perform highly selective recognition, reaction and transfer operations for signal and information processing at the molecular level

Synthesis of an Intercalated Compound of Montmorillonite and 6-Polyamide

Abstract: Natural montmorillonite, fractionated from bentonite produced in Yamagata, Japan, was ion-exchanged for NH 3 + —(CH2)11—COOH, NH 3 + —(CH2)5—COOH, Al3+, Cu2+, Mg2+, Co2+, Li+, K+ and H+. The mixtures of the ion-exchanged montmorillonite and e-caprolactam were heated at 263 °C in glass ampoules for various periods. The intercalated compounds before and after the heating were examined by X-ray powder diffraction, DSC and GPC. Although e-caprolactam was not polymerized without montmorillonite, it was polymerized at 263 °C in the presence of montmorillonite. The polymerization rate varied with the interlayer cations in the order of NH 3 + —(CH2)11—COOH>Al3+>NH 3 + —(CH2)5—COOH>H+>Cu2+>Mg2+>Co2+>Li+>K+. After heating at 263 °C for 5 h, the mean number-average molecular weight was about 1.5 x 104. Although the interlayer distance of NH 3 + —(CH2)11—COOH type montmorillonite/e-caprolactam compound increased from 2.85 nm to 4.90 nm by heating at temperatures above the melting point of e-caprolactam, those of other compounds were not changed. After heating at 263 °C, an intercalated compound of montmorillonite and 6-polyamide, whose interlayer distance was more than 10 nm, was obtained. It is concluded that montmorillonite acts as a Bronsted acid and initiates the open ring polymerization of e-caprolactam and that the driving force of swelling is the polymerization energy.