title: Interaction of pyrophosphate ion with di-, tri- and tetra-amines in aqueous solution: a potentiometric and calorimetric study.
abstract: Successive macroscopic pKa values have been determined potentiometrically for the conjugate acids of spermidine (4-azaoctane-1,8-diamine), spermine (4,9-diazadodecane-1,12-diamine) and some acylic diamines at various ionic strengths in the absence and presence of tetrasodium pyrophosphate. The stability of the amine/pyrophosphate adducts have been estimated on the basis of effects of the pyrophosphate ion on the apparent acidity constants of the amines. Stoichiometry and thermodynamics of adduct formation have been elucidated from microcalorimetric measurements.
authors.affiliation: Department of Inorganic and Analytical Chemistry, Attila Jozsef University, Szeged, Hungary.
authors.forename: I
authors.initials: I
authors.lastname: Labadi
authors.forename: E
authors.initials: E
authors.lastname: Jenei
authors.forename: R
authors.initials: R
authors.lastname: Lahti
authors.forename: H
authors.initials: H
authors.lastname: Lönnberg
mesh_terms: D000588:Amines / Q000737:chemistry*; D002151:Calorimetry; D011756:Diphosphates / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D011199:Potentiometry; D012996:Solutions; D013095:Spermidine / Q000737:chemistry; D013096:Spermine / Q000737:chemistry; D013816:Thermodynamics; D014867:Water
chemical_list: D000588:Amines; D011756:Diphosphates; D012996:Solutions; D014867:Water; D013096:Spermine; D013095:Spermidine