Characterization of single-stranded DNA on chitosan-modified electrode andits application to the sequence-specific DNA detection

Single-strand DNA could bind with chitosan on a platinum electrode via form ing a tight DNA-chitosan complex. The salt concentration of the ssDNA solut ion had an obvious effect on the surface coverage, the immobilization was r emarkably reduced at high salt concentration, The sample ssDNA immobilized on the chitosan-modified electrode can hybridize efficiently with the compl ementary sequences and be successfully used for the sequence-specific DNA d etection. The same results could be obtained using a gold or graphite elect rode modified with chitosan. The stability of this electrode has been also discussed.