KIT | KIT-Bibliothek | Impressum | Datenschutz

Fluoride-induced modulation of ionic transport in asymmetric nanopores functionalized with "caged" fluorescein moieties

Ali, Mubarak; Ahmed, Ishtiaq; Ramirez, Patricio; Nasir, Saima; Cervera, Javier; Niemeyer, Christof M.; Ensinger, Wolfgang

Abstract (englisch):
We demonstrate experimentally and theoretically a nanofluidic fluoride sensing device based on a single conical pore functionalized with “caged” fluorescein moieties. The nanopore functionalization is based on an amine-terminated fluorescein whose phenolic hydroxyl groups are protected with tert-butyldiphenylsilyl (TBDPS) moieties. The protected fluorescein (Fcn-TBDPS–NH2) molecules are then immobilized on the nanopore surface via carbodiimide coupling chemistry. Exposure to fluoride ions removes the uncharged TBDPS moieties due to the fluoride-promoted cleavage of the silicon–oxygen bond, leading to the generation of negatively charged groups on the fluorescein moieties immobilized onto the pore surface. The asymmetrical distribution of these groups along the conical nanopore leads to the electrical rectification observed in the current–voltage (I–V) curve. On the contrary, other halides and anions are not able to induce any significant ionic rectification in the asymmetric pore. In each case, the success of the chemical functionalization and deprotection reactions is monitored through the changes observed in the I–V curves before ... mehr

Open Access Logo

Volltext §
DOI: 10.5445/IR/1000056540
DOI: 10.1039/c6nr00292g
Zitationen: 8
Web of Science
Zitationen: 6
Zugehörige Institution(en) am KIT Institut für Biologische Grenzflächen (IBG)
Publikationstyp Zeitschriftenaufsatz
Jahr 2016
Sprache Englisch
Identifikator ISSN: 2040-3364, 2040-3372
KITopen-ID: 1000056540
HGF-Programm 47.02.01 (POF III, LK 01)
Erschienen in Nanoscale
Band 8
Heft 16
Seiten 8583-8590
Nachgewiesen in Web of Science
KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft
KITopen Landing Page