Ultrasensitive and Selective Copper(II) Detection: Introducing a Bioinspired and Robust Sensor. Issue 39 (17th June 2020)

• Record Type: Journal Article
• Authors: Müller, Lena K.; Duznovic, Ivana; Tietze, Daniel; Weber, Wadim; Ali, Mubarak; Stein, Viktor; Ensinger, Wolfgang; Tietze, Alesia A.
• Is Part Of: Chemistry. Volume 26:Issue 39(2020)
• Page Start: 8511
• Page End: 8517
• Publication Date: 2020-06-17
• Subjects: ATCUN -- copper -- fluorescence -- nanopores -- sensors; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.202001160
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: A nanopore‐based Cu II ‐sensing system is reported that allows for an ultrasensitive and selective detection of Cu II with the possibility for a broad range of applications, for example in medical diagnostics. A fluorescent ATCUN‐like peptide 5/6‐FAM‐Dap‐β‐Ala‐His is employed to selectively bind Cu II ions in the presence of Ni II and Zn II and was crafted into ion track‐etched nanopores. Upon Cu II binding the fluorescence of the peptide sensor is quenched, permitting the detection of Cu II in solution. The ion transport characteristics of peptide‐modified nanopore are shown to be extremely sensitive and selective towards Cu II allowing to sense femtomolar Cu II concentrations in human urine mimics. Washing with EDTA fully restores the Cu II ‐binding properties of the sensor, enabling multiple repetitive measurements. The robustness of the system clearly has the potential to be further developed into an easy‐to‐use, lab‐on‐chip Cu II ‐sensing device, which will be of great importance for bedside diagnosis and monitor of Cu II levels in patients with copper‐dysfunctional homeostasis. Abstract : Capturing copper : The Dap‐β‐Ala‐His sequence, which is generated from the amino‐terminal‐Cu II and Ni II ‐binding motif, is used for a selective binding of Cu II in presence of Ni II and Zn II and was crafted to an ion track‐etched PET membrane. Cu detection was achieved through fluorescence quenching and I–V measurements, enabling femtomolar Cu II concentrations to be sensed.