During the past 15 years, coordination chemistry has rapidly developed toward multicomponent assemblies involving several ligands and metal ions, which are connected via intra- or intermolecular processes. The fascinating structural aspect of these complexation reactions has been early recognized for the design of sophisticated (supra)molecular architectures with novel topologies and functions,...

Ion-molecule complexation dynamics were studied with CH3SCN and Li(+) in acetonitrile by vibrationally probing the nitrile stretching vibration of CH3SCN. The nitrile stretching vibration of CH3SCN has a long lifetime (T1 = ∼90 ps) and its frequency is significantly blue-shifted when CH3SCN is bound with Li(+) ions to form a CH3SCNLi(+) complex in acetonitrile. Such spectral properties enable u...

Various chemical models of ion adsorption are presented and discussed. Chemical models, such as surface complexation models, provide a molecular description of anion adsorption reactions using an equilibrium approach. Two such models, the constant capacitance model and the triple layer model, are described in the present study. Characteristics common to all the surface complexation models are e...

Tracer studies in healthy volunteers using stable isotopes of ruthenium were performed with the objective of extending the limited knowledge about the biokinetics of the radionuclides of this element. Tracer solutions were prepared starting from metallic ruthenium powders enriched in either Ru or Ru (isotopic enrichment ca. 98%). Tracer administration was followed by the collection of blood and...

Objective: The present work describes complexation study of sulfonylurea based drug, glimepiride with divalent metal ions (Mg2+, Ca2+, Cu2+and Zn2+ Methods: The stoichiometry of resulting metal ion-glimepiride complexes were ascertained by molar conductance vs. mole ratio of glimepiride/metal ion plots, Job’s method of continuous variation and liquid chromatography-mass spectrometric analysis. ...

A high dosage of albendazole (ABZ) is required for treating systemic helminthe infections because of its low solubility. Aiming at increasing ABZ solubility, complexation with beta-cyclodextrin ( -CD) using aqueous and acetic acid solutions as ABZ solubilizer was studied. In aqueous -CD, complexation increased solubility 53.4 times, giving a complex equilibrium constant of 1266 L mol with a max...

PURPOSE To investigate the interpolymer complexation between Carbopol 934P (CP) and various grades of polyvinylpyrrolidone (PVP) (K90, K32, C15, and VA/S-630). METHODS Amount of fresh and dried CP-PVP complexes, water retaining capacity, apparent density, pH, conductivity, FTIR, swelling and adhesion strength were studied. RESULTS Interpolymer complexation occurred between CP and all the PV...

Purpose: The solubility of coenzyme Q10 (CoQ10) in water is extremely low, resulting in a low oral bioavailability. In this study, we attempted to improve the low dissolution and bioavailability of CoQ10, by means of the complexation with natural α-, βand γ-cyclodextrins (CyDs) and 2-hydroxypropyl-β-CyD (HP-β-CyD). Methods: The complexation of CoQ10 with CyDs was studied by the solubility metho...

The interaction of mercury (Hg) with dissolved natural organic matter (NOM) under equilibrium conditions is the focus of many studies but the kinetic controls on Hg-NOM complexation in aquatic systems have often been overlooked. We examined the rates of Hg-NOM complexation both in a contaminated Upper East Fork Poplar Creek (UEFPC) in Oak Ridge, Tennessee, and in controlled laboratory experimen...

The irreducible complexation of hemoglobin with spectrin is a natural phenomenon of red blood cell aging, positively correlating with increasing cell density and decreasing cell deformability. The current study begins to address the role of these complexes in the disruption of membrane skeletal physiology and structure. The effect of bound hemoglobin on spectrin dimer self-association was inves...