Publish in OALib Journal
APC: Only $99
A simple and highly
sensitive analysis by electrochemical voltammetry has been developed for
diagnosis of the most destructive crop disease in Thailand known as sugarcane
white leaf (SCWL). Determination of the corresponding DNA interaction has been
obtained from the voltammetric signals of electroactive redox methylene blue
(MB) by means of cyclic and differential pulse voltammetry. In this study, a
chitosan-modified glassy carbon electrode (GCE) was created by self-assembly
to produce electrostatic platform for effective immobilization of the DNA.
Fabrication of SCWL-DNA
hybridization detection system was performed by immobilizing the ssDNA probe as a specific sensor
onto chitosan-modified GCE. Hybridization of complementary DNA from the real
samples could then be detected by its respective MB signal. This fabricated DNA probe sensor was shown to be
capable for discriminative identification among the DNAs from SCWL plants,
mosaic virus infected sugarcane and healthy sugarcane plants. Relationship
between the specific hybridization signal and DNA target concentration was also
observed under optimal condition. The detection limit of 4.709 ng/μl with the regression coefficient (R2)
of 0.998 and overall RSD of 2.44% were obtained by response curve fit analysis.
The actual SCWL-ssDNA immobilization and hybridizing event were subsequently
confirmed by an observation under atomic force microscope. Thus these experiments demonstrate the first successful and effective DNA based voltammetric
electrochemical determination for a verification of the specific pathogenic
infection within plants from the real epidemic field.