Issue 23, 2015

Multifunctional self-assembled composite colloids and their application to SERS detection

Abstract

We present a simple method for the co-encapsulation of gold nanostars and iron-oxide nanoparticles into hybrid colloidal composites that are highly responsive to both light and external magnetic fields. Self-assembly was driven by hydrophobic interactions between polystyrene capped gold nanostars and iron oxide nanocrystals stabilized with oleic acid, upon addition of water. A block copolymer was then used to encapsulate the resulting spherical colloidal particle clusters, which thereby became hydrophilic. Electron microscopy analysis unequivocally shows that each composite particle comprises a single Au nanostar surrounded by a few hundreds of iron oxide nanocrystals. We demonstrate that this hybrid colloidal system can be used as an efficient substrate for surface enhanced Raman scattering, using common dyes as model molecular probes. The co-encapsulation of iron oxide nanoparticles renders the system magnetically responsive, so that application of an external magnetic field leads to particle accumulation and limits of detection are in the nM range.

Graphical abstract: Multifunctional self-assembled composite colloids and their application to SERS detection

Supplementary files

Article information

Article type
Paper
Submitted
24 Feb 2015
Accepted
16 Apr 2015
First published
22 Apr 2015
This article is Open Access
Creative Commons BY license

Nanoscale, 2015,7, 10377-10381

Author version available

Multifunctional self-assembled composite colloids and their application to SERS detection

A. La Porta, A. Sánchez-Iglesias, T. Altantzis, S. Bals, M. Grzelczak and L. M. Liz-Marzán, Nanoscale, 2015, 7, 10377 DOI: 10.1039/C5NR01264C

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements