title: Novel potentiometric and optical silver ion-selective sensors with subnanomolar detection limits.
abstract: Ten Ag+-selective ionophores have been characterized in terms of their potentiometric selectivities and complex formation constants in solvent polymeric membranes. The compounds with pi-coordination show much weaker interactions than those with thioether or thiocarbamate groups as the coordinating sites. Long-term studies with the best ionophores show that the lower detection limit of the best Ag+ sensors can be maintained in the subnanomolar range for at least 1 month. The best ionophores have also been characterized in fluorescent microspheres. The so far best lower detection limits of 3 x 10(-11) M (potentiometrically) and 2 x 10(-11) M Ag+ (optically) are found with bridged thiacalixarenes.
authors.affiliation: Laboratorium für Organische Chemie, ETH Zürich, CH-8093 Zürich, Switzerland.
authors.forename: Zsófia
authors.initials: Z
authors.lastname: Szigeti
authors.forename: Adam
authors.initials: A
authors.lastname: Malon
authors.forename: Tamás
authors.initials: T
authors.lastname: Vigassy
authors.forename: Viktor
authors.initials: V
authors.lastname: Csokai
authors.forename: Alajos
authors.initials: A
authors.lastname: Grün
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Wygladacz
authors.forename: Nan
authors.initials: N
authors.lastname: Ye
authors.forename: Chao
authors.initials: C
authors.lastname: Xu
authors.forename: Vincent J
authors.initials: VJ
authors.lastname: Chebny
authors.forename: István
authors.initials: I
authors.lastname: Bitter
authors.forename: Rajendra
authors.initials: R
authors.lastname: Rathore
authors.forename: Eric
authors.initials: E
authors.lastname: Bakker
authors.forename: Ernö
authors.initials: E
authors.lastname: Pretsch