Ultrasensitive and selective copper (II) detection: introducing a bioinspired and robust sensor.

We report a nanopore-based Cu(II) sensing system which allows for an ultrasensitive and selective detection of Cu(II) with the possibility for a broad range of applications, i.e. 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. PMID: 32196774 [PubMed - as supplied by publisher]
Source: Chemistry - Category: Chemistry Authors: Tags: Chemistry Source Type: research