TY  - JOUR
A1  - Dechtrirat, Decha
A1  - Gajovic-Eichelmann, Nenad
A1  - Wojcik, Felix
A1  - Hartmann, Laura
A1  - Bier, Frank Fabian
A1  - Scheller, Frieder W.
T1  - Electrochemical displacement sensor based on ferrocene boronic acid tracer and immobilized glycan for saccharide binding proteins and E. coli
JF  - Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics
N2  - Pathogens such as viruses and bacteria use their envelope proteins and their adhesin lectins to recognize the glycan residues presented on the cell surface of the target tissues. This principle of recognition is used in a new electrochemical displacement sensor for the protein concanavalin A (ConA). A gold electrode was first modified with a self-assembled monolayer of a thiolated mannose/OEG conjugate and a ferrocene boroxol derivative was pre-assembled as reporter molecule onto the mannose surface. The novel tracer molecule based on a 2-hydroxymethyl phenyl boronic acid derivative binds even at neutral pH to the saccharides which could expand the application towards biological samples (i.e., urine and feces). Upon the binding of ConA, the tracer was displaced and washed away from the sensor surface leading to a decrease in the electrochemical signal. Using square wave voltammetry (SWV), the concentration of ConA in the sample solution could be determined in the dynamic concentration range established from 38 nmol L-1 to 5.76 mu mol L-1 with a reproducible detection limit of 1 mu g mL(-1) (38 nmol L-1) based on the signal-to-noise ratio (S/N=3) with fast response of 15 min. The new reporter molecule showed a reduced non-specific displacement by BSA and ribonuclease A. The sensor was also successfully transferred to the first proof of principle for the detection of Escherichia coli exhibiting a detection limit of approximately 6 x 102 cells/mL Specificity of the displacement by target protein ConA and E. coli was demonstrated since the control proteins (i.e., BSA and RNaseA) and the control E. coli strain, which lack of type 1 fimbriae, were ineffective. (C) 2014 Elsevier B.V. All rights reserved.
KW  - Ferrocene benzoboroxol biosensor
KW  - Concanavalin A
KW  - Displacement
KW  - Escherichia coli
KW  - Ferrocene boronic acid
KW  - Self-assembled monolayer
Y1  - 2014
U6  - https://doi.org/10.1016/j.bios.2014.02.028
SN  - 0956-5663
SN  - 1873-4235
VL  - 58
SP  - 1
EP  - 8
PB  - Elsevier
CY  - Oxford
ER  -