The synthesis of ligand L based on a 2,6-bis[(N,N-bis(methylene phosphonic acid)aminomethyl] pyridine scaffold is described. Potentiometry combined with UV-Vis absorption spectrophotometric titrations were used to determine the protonation constants of the ligand and the stability constants of its corresponding Cu(II), Ni(II), Zn(II) and Ga(III) cations (0.1 M NaClO(4), 25.0 °C). The physico-ch...

the interaction of bovine serum albumin ( bsa) and egg albumin with water solublephthalocyanine, cobalt (ιι) 4, 4′ , 4′′, 4′′′- tetrasulfophthalocyanine ( cotspc) , has been studiedby the uv- vis method at ph 7.0 and five different temperatures 20, 25, 30, 35 and 40°c. theformation constants have been elucidated by using spectrophotometric titration and computersquad program data refinement. th...

Protonation and carbamate formation are critical reactions for CO2 capture using amine-based absorbents which impact both absorption amine regeneration. In this regard, thermodynamic analysis towards in N-methylaminoethanol solution is carried out with specific attention to the corresponding protonation reactions. The mechanism investigated acquisition of reaction equilibrium constant heat reac...

The existence of protonated hydroxymethylamines of sec+ ondary amines, RzNHCHtOH, in equilibrium with hydroxymethylamines and protonated amines, has been demonstrated by titration at equilibrium and by rapid titration of the protonated hydroxymethylamines. Analogous compounds, . R3NCHeOH, are formed from formaldehyde and the sterically favorable tertiary amines: pyridine, iv-methylimidazole, an...

The existence of protonated hydroxymethylamines of sec+ ondary amines, RzNHCHtOH, in equilibrium with hydroxymethylamines and protonated amines, has been demonstrated by titration at equilibrium and by rapid titration of the protonated hydroxymethylamines. Analogous compounds, . R3NCHeOH, are formed from formaldehyde and the sterically favorable tertiary amines: pyridine, iv-methylimidazole, an...

Central to Alzheimer's disease (AD) is the assembly of amyloid-beta peptide (Aβ) into fibrils. A reduction in pH accompanying inflammation or subcellular compartments, may accelerate fibril formation as approaches Aβ’s isoelectric point (pI). Using global fitting kinetics over a range pHs, we identify impact net charge has on individual microscopic rate constants. We show that primary nucleatio...

The protonation constants of glycine, L-alanine, glycyl-glycine, glycyl-glycyl-glycine and glycyl-L-alanine have been determined in 10-80% (v/v) ethanol-water mixtures at 25 °C and constant ionic strength (0.1 mol L-1 sodium perchlorate), by potentiometric technique and calculated using a suitable computer program, which employs a nonlinear least-squares method. The effect of solvent compositio...