Biology Reference
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designed for electrochemically fast, sensitive, selective, and low-
cost detection and characterization of surface active compounds
[6, 7, 15, 21]. To obtain sensitive EVLS signals, the elimination
method analyzes voltammetric curves measured at different scan
rates and in connection with adsorptive techniques works with
small amount of samples utilizing strong adsorption of analyte on
the electrode surface. EVLS was applied mostly to the resolution of
reduction signals of adenine (A) and cytosine (C) in short synthetic
homo- and hetero-ODNs [10, 15, 44, 45], but preliminary results
showed that the chosen elimination functions would be useful for
the study of anodic processes, especially for the anodic processes
of guanine [47-49]. For an adsorbed electroactive substance, the
elimination function E4 (the simultaneous elimination of charging
and kinetic currents, and conservation of diffusion current) gives
a well-readable peak-counterpeak, which has been successfully
utilized in the analysis of overlapped reduction signals of A and
C on HMDE [10, 15, 44, 45]. Using the AdTS procedure, ODNs
were immobilized at the HMDE surface from a small drop of the
analyzed solution (5
μ
L); then the ODN-modified electrode was
washed and immersed into buffer solutions (not containing ODN)
to perform voltammetric measurements [35]. Our new analytical
approachcontributedtothetransformationofLSVdata(overlapped
signal) to EVLS data (resolved signal).
The sparingly soluble complex of Cu(I)-purine reduced at
mercuryelectrodesandoxidizedatcarbonelectrodes(carbonpaste
or carbon pencil electrodes) was recently utilized for the sensitive
detection of purine derivatives [69]. It was found that this complex
has a synergic effect for reduction or oxidation of corresponding
nucleobases because it brings more electroactive materials to the
electrode surfaces. Purine signals processed AdS and AdTS EVLS
and were 15 times more enhanced than the original signal. The
advantage of mercury and carbon electrodes is a good adsorption
capability ofthis complex on their surface.
In summary, our research showed that the EVLS is not limited to
mercury electrodes, to reduction processes, or to the elimination of
one current component only. Voltammetric signals of purine deriva-
tivesatcarbonelectrodesareamplifiedusingourapproaches.Com-
pared to elimination in various combinations (different functions
