Development of electrochemical DNA biosensor for Trichoderma harzianum based on ionic liquid/ZnO nanoparticles/chitosan/gold electrode

Journal of Solid State Electrochemistry (Impact Factor: 2.28). 01/2012; 16(1):273-282. DOI: 10.1007/s10008-011-1322-y

ABSTRACT Electrochemical DNA biosensor was successfully
developed by depositing the ionic liquid (e.g., 1-ethyl-3-
methylimidazolium trifluoromethanesulfonate ([EMIM]
[Otf])), ZnO nanoparticles, and chitosan (CHIT) nanocomposite
membrane on a modified gold electrode (AuE). The
electrochemical properties of the [EMIM][Otf]/ZnO/CHIT/
AuE for detection of DNA hybridization were studied. Under
optimal conditions using cyclic voltammetry, the target DNA
sequences could be detected in the concentration range of
1.0×10−18 to 1.82×10−4 mol L−1, and with the detection limit of 1.0×10−19 mol L−1. This DNA biosensor detection
approaches provide a quick, sensitive, and convenient method
to be used in the identification of Trichoderma harzianum

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