Characterization of gold nanoparticles modified with single-stranded DNA using analytical ultracentrifugation and dynamic light scattering

Published

August 3, 2010

Author(s)

James Falabella, Tae Joon Cho, Dean C. Ripple, Vincent A. Hackley, Michael J. Tarlov

Abstract

We report the characterization of gold nanoparticles modified with thiol-terminated single stranded DNA using analytical ultracentrifugation and dynamic light scattering. Sedimentation coefficients of nominally 10 and 20 nm diameter gold nanoparticles modified with thiol-terminated thymidine homo-oligonucleotides, 5 to 30 bases in length, were determined with analytical ultracentrifugation. The sedimentation coefficients of the gold nanoparticles were found to decrease with increasing coverage of DNA and increasing number of thymidine nucleotides (dT). It was found that sedimentation coefficients for DNA modified gold particles were most closely predicted when the strands were modeled as fully extended chains (FEC). Calculation of apparent particle density from the measured sedimentation coefficient revealed that as the bare particle size decreased a significant hydration layer greatly begins to reduce the apparent density of bare and short DNA chain modified gold particles.

Citation

Langmuir

Volume

26

Issue

15

Pub Type

Journals

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Keywords

gold nanoparticles, ssDNA modified, analytical ultracentrifugation, hydration effects.

Citation

Falabella, J. , Cho, T. , Ripple, D. , Hackley, V. and Tarlov, M. (2010), Characterization of gold nanoparticles modified with single-stranded DNA using analytical ultracentrifugation and dynamic light scattering, Langmuir, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=904829 (Accessed December 14, 2024)