Abstract:
We report the growth of Pt nanoparticles (NP) coupled and stabilized in situ with glucose oxidase (GOx). The enzyme-capped-Pt nanoparticles were formed from K2PtCl6 (aq) reduced with H2 (g) in the presence of GOx at a molar ratio of 889-1 Pt(IV)-GOx, creating a direct-linkage between NP and protein during particle growth. Transmission electron microscopy imaging revealed the formation of fcc Pt nanocrystals in the presence of the enzyme with an average dimension andlt;dandgt; - 4.05 ± 0.62 nm, whereas in its absence Pt black precipitated from solution. This is evidence that the glycoprotein terminated propagation of Pt growth and stabilized the NP surface. Transfer of Pt NP-GOx to an electrode by assembly on poly(diallyldimethylammonium chloride) allowed amperometric glucose determination with a low limit of detection of ca. 30 μM. © 2008 American Chemical Society.