Stable 8-hydroxyquinolinate-based podates as efficient sensitizers of lanthanide near-infrared luminescence

摘要: New polydentate ligands (e.g., Tsox and TsoxMe) have been synthesized to take advantage of the chelating effect bidentate 8-hydroxyquinolinate subunits connected a N,N,N‘,N‘-tetraaminopropyl-1,2-ethylenediamine framework with aim sensitizing NIR luminescence NdIII YbIII ions. Ten pKa's determined interaction between LnIII ions in dilute aqueous solution has probed both by potentiometric spectrophotometric titrations. These studies mostly performed EuIII ion, which is middle lanthanide series, extended other (LaIII, ErIII, LuIIII). Stable complexes are formed (pLn range 14−16), four chromophoric units being coordinated metal center, exploiting entropic generated anchor. The monometallic [Ln(H2L)]3- exist as major species at physiological pH regardless used. Lifetime determinations Nd(4F3/2) Yb(2F...