Posted 3 years ago
Whole cell based microcontact imprinted capacitive biosensor for the detection of Escherichia coli
Neslihan Idil a,b, Martin Hedström a,c, Adil Denizli d, Bo Mattiasson a,c,⁎
a Department of Biotechnology, Lund University, Lund, Sweden
b Department of Biology, Faculty of Sciences, Hacettepe University, Ankara, Turkey
c CapSenze Biosystems AB, Lund, Sweden
d Department of Chemistry, Faculty of Sciences, Hacettepe University, Ankara, Turkey
A R T I C L E I N F O
A B S T R A C T
In this study, a label-free, selective and sensitive microcontact imprinted capacitive biosensor was developed for
the detection of Escherichia coli. The recognition of E. coli was successfully performed by this sensor prepared
with the combination of microcontact imprinting method and capacitive biosensor technology. After preparation
of bacterial stamps, microcontact-E. coli imprinted gold electrodes were generated using an amino acid
based recognition element, N-methacryloyl-L-histidine methylester (MAH), 2-Hydroxyethyl methacrylate
(HEMA) as monomers and ethyleneglycol dimethacrylate (EGDMA) as crosslinker under UV-polymerization.
Real-time E. coli detection experiments were carried out within the range of 1.0Å~102–1.0Å~107 CFU/mL. The
unique combination of these two techniques provides selective detection with a detection limit of 70 CFU/mL.
The designed capacitive sensor has high selectivity and was able to distinguish E. coli when present together
with competing bacterial strains which are known to have similar shape. In addition, the prepared sensor has
the ability to detect E. coli with a recovery of 81–97% in e.g. river water.