Issue 7, 2014

A ferritin mediated photochemical method to synthesize biocompatible catalytically active gold nanoparticles: size control synthesis for small (∼2 nm), medium (∼7 nm) or large (∼17 nm) nanoparticles

Abstract

Ferritin (Ftn) undergoes photo-induced charge separation reactions that oxidize organic substrates. The liberated electrons are transferred through the protein shell to reduce Au ions to gold nanoparticles (AuNPs). We systematically varied the concentrations of citrate (electron donor), Au3+ or Au+ (electron acceptor), and ferritin (photo catalyst) to determine if careful control of these reactant concentrations would: (1) provide size control; (2) alter the morphology of the resulting AuNPs; and (3) alter the catalytic activity of the resulting AuNPs. The size and phosphate content of the ferritin iron core was also evaluated for its influence in this photocatalysis reaction. We report that as the Ftn concentration was increased to an optimal range, the number of AuNPs increased and showed smaller size, more spherical shape, and narrower distribution. Increasing the citrate concentration (electron donor) increased the rate of AuNP formation producing more spherical, uniform sized AuNPs. Increasing the Au3+ concentrations increased the number and sizes of the AuNPs. Since Au3+ reduction requires 3-electrons we proposed that using Au+ would increase the rate of the reaction. The photochemical reaction with Au+ was faster and produced 2.4 ± 1.0 nm diameter AuNPs providing another method of size control. AuNPs were tested as reduction catalysts to convert 4-nitrophenol into 4-aminophenol. The smaller spherical AuNPs were better reduction catalysts than the larger AuNPs. In summary, using a single photochemical synthesis method we can reproducibly control the size, uniformity and catalytic activity of the resulting AuNPs simply by varying the concentrations or oxidation states of the reactants.

Graphical abstract: A ferritin mediated photochemical method to synthesize biocompatible catalytically active gold nanoparticles: size control synthesis for small (∼2 nm), medium (∼7 nm) or large (∼17 nm) nanoparticles

Supplementary files

Article information

Article type
Paper
Submitted
08 Nov 2013
Accepted
02 Dec 2013
First published
03 Dec 2013

RSC Adv., 2014,4, 3472-3481

A ferritin mediated photochemical method to synthesize biocompatible catalytically active gold nanoparticles: size control synthesis for small (∼2 nm), medium (∼7 nm) or large (∼17 nm) nanoparticles

O. D. Petrucci, D. C. Buck, J. K. Farrer and R. K. Watt, RSC Adv., 2014, 4, 3472 DOI: 10.1039/C3RA46520A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements