Enhanced bioconjugation on sputtered palladium nano-thin-film electrode

Abstract

A highly reactive surface with an enhanced ability for chemical bonding relies on the presence of specifically coordinated atoms and step edges at the surface. In this study, an electrode with a unique Stranski-Krastanov-like thin film, with an epitaxial sputtering of a palladium (Pd) nanoparticle double layer on the polyethylene terephthalate substrate, was developed. On the surface of this flexible Pd-nano-thin-film (NTF) electrode with a (1 1 1) containing surface, DNA probes can be quickly immobilized in as short a period as 20 min, which is 24 times faster than that on the gold electrode. A DNA-based anticancer compound (ACC) sensing and screening process that would use the DNA functionalized Pd-NTF electrode as the biosensor was then proposed. Interestingly, the developed biosensor could detect DNA and ACCs, such as doxorubicin, tetra-O-methyl nordihydroguaiaretic acid, and Taxol via interactions with solutions containing 1 mu l ACCs within 11 min, and the sensitivity of the ACC solution is similar to 0.1 mu M (similar to 36 pg per-test), as detected by electrochemical impedance spectroscopy. Moreover, this highly reactive surface can be used in regular sensors and other interfaces, in scientific applications. (C) 2019 Author(s).