Biosensing for the Environment and Defence: Aqueous Uranyl Detection Using Bacterial Surface Layer Proteins
Biosensing for the Environment and Defence: Aqueous Uranyl Detection Using Bacterial Surface Layer Proteins
Conroy, D. J. R.; Millner, P. A.; Stewart, D. I.; Pollmann, K.
The fabrication of novel uranyl (UO2 2+) binding protein based sensors is reported. The new biosensor responds to picomolar levels of aqueous uranyl ions within minutes using Lysinibacillus sphaericus JG-A12 S-layer protein tethered to gold electrodes. In comparison to traditional self assembled monolayer based biosensors the porous bioconjugated layer gave greater stability, longer electrode life span and a denser protein layer. Biosensors responded specifically to UO2 2+ ions and showed minor interference from Ni2+, Cs+, Cd2+ and Co2+. Chemical modification of JG-A12 protein phosphate and carboxyl groups prevented UO2 2+ binding, showing that both moieties are involved in the recognition to UO2 2+.
Keywords: S-layer; surface layer; protein biosensor; uranium; uranyl; metal ion; sequestering; impedance spectroscopy
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Sensors 10(2010), 4739-4755
DOI: 10.3390/s100504739
ISSN: 1424-8220
Cited 18 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-14204