Biology Reference
In-Depth Information
amperometric transducers are most used in biosensors due to
their high sensitivity and selectivity. Except an indication electrode,
the electrochemical system contains other two electrodes, that
is, a reference electrode and an auxiliary electrode [1-4]. Our
approach in electrochemical oligonucleotide (ODN) transducer is
built on the adsorptive stripping voltammetric (AdSV) technique
in connection with elimination voltammetry with linear scan
(EVLS). Generally, EVLS enables the elimination of selected partial
voltammetric currents and the conservation of the other one
contributing to the increase of current sensitivity, the expansion of
electrode potential range (potential window) and the separation of
overlapped voltammetric signals. The basic idea of EVLS procedure
lies in the different dependencies of various voltammetric current
componentsonthescanrate.Theeliminationresultcanbeachieved
by a function obtained by linear combination of total voltammetric
currents measured at different scan rates [5, 6].
11.2 Theoretical Fundamentals of Elimination
Voltammetry with Linear Scan (EVLS)
11.2.1
Elimination Functions
Fourteen years ago, the theory of elimination voltammetry with
linear scan (EVLS) was published and experimentally verified for
selected electrode systems [5, 6]. To this date, the method has
been applied not only in electroanalytical chemistry, but also in the
study of electrode processes of inorganic and organic electroactive
substances at mercury, silver, or graphite electrodes [7-20]. EVLS
can be considered as a mathematical model of the transformation
of current-potential curves capable of eliminating certain selected
current components while securing the conservation of others by
means of elimination functions. For the calculation of the elimina-
tion functions, two or three voltammetric curves at different scan
rates should be recorded under identical experimental conditions.
It means that the linear sweep voltammetric (LSV) curves have to
be recorded with the same potential step, so that the
I
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E
data sets
obtained for the same number of points on the potential axis, and