Probing the conjugation of gold NPs using single-stranded DNA comprising two polyadenine adhesive tails

ABSTRACT

The spatial arrangement of nanoobjects by using DNA is a promising nano-design technology. Polyadenine adhesive tails are increasingly used to anchor functional oligonucleotides on the surface of gold nanoparticles at low pH. Further hybridization of such functional oligonucleotides allows nanoparticles to be organized within the desired design. In this work, we studied the effect of temperature, ionic strength, and strand design on the adsorption rate of polyadenines on the surface of gold nanoparticles at different pH. We found that there are temperature and ionic strength ranges in which the adsorption rate increases and vice versa. There are also significant differences in the effects of monovalent sodium and divalent magnesium ions. We have shown that dual-tail DNA strand design allows for increased surface density, which is significantly higher than that obtained with the standard one-tail strand design.

KEYWORDS:

• DNA
• polyadenine
• gold nanoparticles
• conjugation
• ATP aptamer
• biosensor

Acknowledgements

This study was supported by the Russian Science Foundation (project no. 19-73-00113 and no. 22-25-00302). The research was carried out using resources provided by SPbU Resource Centers for Nanotechnology and for Diagnostics of Functional Materials for Medicine, Pharmacology and Nanoelectronics. The authors acknowledge SevSU for a research Grant 42-01-09/90/2020-4.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the SevSU [42-01-09/90/2020-4]; Russian Science Foundation [19-73-00113,22-25-00302].