Polypyrrole colloidal nanospheres as an effective fluorescent sensing platform for DNA detection

Abstract: In the present study, we demonstrate the first use of polypyrrole colloidal nanospheres (PPyCNPs) as an effective sensing platform for fluorescence-enhanced DNA detection by the following two steps: (1) PPyCNP adsorbs and quenches a dye-labeled single-stranded DNA (ssDNA) probe; (2) The subsequent hybridization of the probe with its target produces a double-stranded DNA (dsDNA) which detaches from PPyCNP, leading to recovery of dye fluorescence. The present system shows a detection limit as low as 1nM and has a high selectivity down to single-base mismatch. [Copyright &y& Elsevier]