of five successive increases and decreases of the temperature
Acknowledgements
from 15 to 80 1C were recorded.
The authors thank bioMe
´
rieux for the financial support of
´
Gregory Chatelain’s PhD thesis and for providing the gold
Thermodynamic parameter calculation (Tm, DS1, DH1 and DG1298
)
electrode systems. This research is supported by the ANR
(French national research agency) through the project VirProbe
(PIRIBio program), the Lyonbiopole and Eurobiomed clusters.
Dissociation constants (K(T)) were calculated for Fc5-a-DNA/
target duplexes as described by Breslauer and Marky51 and
Durand et al.52 A van’t Hoff plot of Ln(K(T)) versus 1/T was
generated for duplex formation. The slope and intercept of the
calculated line yielded to the enthalpy (DH1) and the entropy
(DS1), respectively, as described in the ESI.w Then, the Gibbs
free energy at 298 K (DG1298) was calculated according to the
following equation:
Notes and references
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´
(Marcy-l’Etoile, France). It contained eight sensing plots made
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Method. Experiments on a biochip were performed in a 10 mL
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on the biochip’s gold electrodes and the system was left for
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Hybridization assays
Hybridization tests were carried out by introducing the target
in the droplet. Electrochemical response was followed by CV
before and after the target addition (scan rate: 100 mV sꢀ1
;
potential range: ꢀ300 mV/+300 mV). [Fc5-a-DNA] = 10 mM
and [target] = 55 mM (5.5 eq.).
c
900 New J. Chem., 2011, 35, 893–901
This journal is The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2011