title: Design and synthesis of a novel magnetic resonance imaging contrast agent for selective sensing of zinc ion.
abstract: A series of new diethylenetriaminepentaacetic acid (DTPA)-bisamide chelators has been prepared and characterized for application as zinc sensors. We have designed and synthesized (GdL(a))(2-), which contains a DTPA-bisamide moiety. The R(1) relaxivity of (GdL(a))(2-) solution decreased monotonically on the addition of Zn(2+). Moreover, (GdL(a))(2-) showed high selectivity for Zn(2+) against Ca(2+) and Mg(2+). We also measured the UV-visible spectra and the coldspray ionization (CSI) MS spectra and concluded that the 1-to-1 Zn(2+) complex of (GdL(a))(2-) is stable at higher concentrations of Zn(2+). These complexes should provide the basis for creating a superior Zn(2+)-sensitive MRI contrast agent and are excellent candidates for incorporation into sensors designed for selective detection of Zn(2+) in biological applications.
mesh_terms: D002412:Cations; D002614:Chelating Agents / Q000737:chemistry; D003287:Contrast Media / Q000737:chemistry*; D019786:Gadolinium DTPA / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008956:Models, Chemical; D011522:Protons; D012680:Sensitivity and Specificity; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet; D015032:Zinc / Q000032:analysis* / Q000737:chemistry
chemical_list: D002412:Cations; D002614:Chelating Agents; D003287:Contrast Media; D011522:Protons; D012996:Solutions; D015032:Zinc; D019786:Gadolinium DTPA