Nucleic Acid-Functionalized Pt Nanoparticles: Catalytic Labels for the Amplified Electrochemical Detection of Biomolecules

Nucleic acid-functionalized Pt nanoparticles (Pt-NPs) act as catalytic labels for the amplified electrochemical detection of DNA hybridization and aptamer/protein recognition. Hybridization of the nucleic acid-modified Pt-NPs with a sensing nucleic acid/analyte DNA complex associated with an electrode enables the amperometric, amplified, detection of the DNA by the Pt NP electrocatalyzed reduction of H2O2 (sensitivity limit, 1 × 10-11 M). Similarly, the association of aptamer-functionalized Pt- NPs to a thrombin aptamer/thrombin complex associated with an electrode allowed the amplified, electrocatalytic detection of thrombin with a sensitivity limit corresponding to 1 × 10-9 M.