Adsorption is the net accumulation of a chemical species at the interface between a solid phase and an aqueous solution phase, leading to a loss from the solution phase (Sposito, 1989). Adsorption reactions can be described by various models. Empirical models provide descriptions of adsorption data without theoretical basis. Examples are the distribution coefficient, the Freundlich adsorption i...

(1)H NMR spectroscopy (500 MHz) has been used to quantify the complexation of the antibacterial antibiotic Norfloxacin (NOR) with DNA in the presence of Caffeine (CAF). Separate studies have been made for the self-association of NOR, its hetero-association with CAF and complexation with a model self-complementary DNA tetramer, 5'-d(TpGpCpA), in order to determine the equilibrium parameters (ind...

the complexive abilities of 5,11,17-tddert-butyl-23 amino-25.26,27,28-tet3propoxy-calix[4]arere and5,1127-tri-amino-23 acelyktert-butylamide-25,26,27,28-tetrabutoxy-calixplarene towards alkali metalions lit nat, kt ric and cs+ in methanol-chloroform mixture have been evaluated at 25 °c, using uvvis spectrophotometric techniques. the results showed that the hgands are capable to complex with all...

a new schiff base ligand, 2,2'-{pyridine-2,6-diylbis[nitrilo(e)methylylidene]}bis(4 bromophenol),has been synthesized by reaction of the 2,6-diamino pyridine with 5-bromo salicylaldehyde at ethanolunder refluxing. the structure of the synthesized compound resulted from the ir, 1hnmr, ms anduv spectroscopy and elemental analysis data. formation constant (kf) value of it’s complexes withcu2+, ni2...

the complex formed as a consequence of the interaction between the electron-acceptor p-chloranilic acid and an electron donor tamoxifen citrate was employed in the assay of the drug in pure powder and tablets. chloranilic acid was found to form a charge-transfer complex in a 1:1 stoichiometric ratio, with tamoxifen citrate. the wavelength of maximum absorption for the complex was found to be 55...

lysozyme, as a model protein, was precipitated through the formation of protein-zn complex to micronize for subsequent encapsulation within poly (lactic-co-glycolic acid) (plga) microspheres. various parameters, including ph, type and concentration of added salts and protein concentration, were modified to optimize the yield of protein complexation and precipitation. the resulting protein parti...

– The complexation of oppositely charged colloidal objects is considered in this paper as a thermodynamic micellization process where each kind of object needs the others to micellize. This requirement gives rise to quantitatively different behaviors than the so-called mixed-micellization where each specie can micellize separately. A simple model of the grand potential for micelles is proposed ...