Issue 18, 2014

“Red-to-blue” colorimetric detection of cysteine via anti-etching of silver nanoprisms

Abstract

The reported strategies for cysteine (Cys) colorimetric detection based on noble metal nanomaterials include triggering aggregation, etching or fluorescence quenching of nanomaterials by Cys. In this study, we propose a new strategy for Cys colorimetric detection, i.e. anti-etching of silver nanoprisms (AgNPRs). In the absence of Cys, iodide ions (I) could etch the corners and edges of AgNPRs and induce the morphology transition from nanoprism to nanodisk, which results in color change of the AgNPR dispersion from blue to red. In its presence, however, Cys can prevent the AgNPRs from I attack. In that case, the color of the AgNPR dispersion containing I and Cys remains blue. The mechanism is confirmed by using UV-vis spectra, TEM, DLS, Raman spectra and XPS spectra. According to the sensing effect of the Cys detection system, the concentration of I incubated with AgNPRs, incubation time of AgNPRs and I, and pH of AgNPR dispersions are optimized to 5.0 μM, 10 min, and pH 6.2, respectively. Under the optimized conditions, the proposed Cys detection system has excellent selectivity and high sensitivity. The limit of detection (LOD) of our Cys detection system is 25 nM by the naked eye, which is much better than the reported lowest LOD by eye-vision (100 nM), and 10 nM by UV-vis spectroscopy. The results of Cys detection in rabbit urine or plasma samples reinforce that our Cys detection system is applicable for rapid colorimetric detection of Cys in real body fluid samples.

Graphical abstract: “Red-to-blue” colorimetric detection of cysteine via anti-etching of silver nanoprisms

Supplementary files

Article information

Article type
Paper
Submitted
16 Jun 2014
Accepted
27 Jun 2014
First published
03 Jul 2014

Nanoscale, 2014,6, 10631-10637

Author version available

“Red-to-blue” colorimetric detection of cysteine via anti-etching of silver nanoprisms

Y. Li, Z. Li, Y. Gao, A. Gong, Y. Zhang, N. S. Hosmane, Z. Shen and A. Wu, Nanoscale, 2014, 6, 10631 DOI: 10.1039/C4NR03309D

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