An electrochemical impedance sensor based on a small molecule modified Au electrode for the recognition of a trinucleotide repeat

摘要: A small molecule modified sensor was developed for the detection of XGG trinucleotide repeats (X = C, T) by electrochemical impedance spectroscopy. The (NCD/MPA/Au) fabricated immobilizing nucleic acid recognition (NCD) on surface a gold electrode through condensation reaction between amino-terminal end NCD linker and carboxylic groups in 3-mercaptopropionic that were self-assembled surface. After incubated with repeats, spectroscopy performed using [Fe(CN)6]3−/4− as redox marker ions. could be selectively detected based differences charge transfer resistance (ΔRct) even presence other repeats. relationship ΔRct lg [concentration CGG repeats] linear from 1 nM to μM, enabling quantification number provides simple rapid method detect without requiring labelling immobilizations DNA, making it promising early diagnosis neurodegenerative diseases; may further extended special sequences DNA.