%0 Journal Article
%T Biosensing for the Environment and Defence: Aqueous Uranyl Detection Using Bacterial Surface Layer Proteins
%A David J.R. Conroy
%A Paul A. Millner
%A Douglas I. Stewart
%A Katrin Pollmann
%J Sensors
%D 2010
%I MDPI AG
%R 10.3390/s100504739
%X The fabrication of novel uranyl (UO22+) 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 UO22+ ions and showed minor interference from Ni2+, Cs+, Cd2+ and Co2+. Chemical modification of JG-A12 protein phosphate and carboxyl groups prevented UO22+ binding, showing that both moieties are involved in the recognition to UO22+.
%K S-layer
%K surface layer
%K protein biosensor
%K uranium
%K uranyl
%K metal ion
%K sequestering
%K impedance spectroscopy
%U http://www.mdpi.com/1424-8220/10/5/4739