Issue 20, 2018

Highly sensitive detection of exosomes by SERS using gold nanostar@Raman reporter@nanoshell structures modified with a bivalent cholesterol-labeled DNA anchor

Abstract

Exosomes, as important signal transmitters, play a key role in intercellular communication, especially in cancer metastasis. There is considerable evidence that exosomes can be used as an indicator of cancer. However, convenient and sensitive methods for detecting exosomes are still technically challenging. Here, we present a convenient and highly sensitive surface-enhanced Raman scattering (SERS) based method by combining immunoaffinity, SERS nanoprobes, and portable Raman devices for specific isolation and accurate quantification of exosomes. To construct the SERS-based biosensor, the surfaces of gold nanostar@4-mercaptobenzoic acid@nanoshell structures (AuNS@4-MBA@Au) are modified with a bivalent cholesterol (B-Chol)-labeled DNA anchor to prepare SERS nanoprobes. Exosomes are specifically captured by immunomagnetic beads, and then SERS nanoprobes are fixed on the surface of exosomes by hydrophobic interactions between cholesterol and lipid membranes, thus forming a sandwich-type immunocomplex. The immunocomplex can be magnetically captured and produce enhanced SERS signals. In the absence of exosomes, the sandwich-type immunocomplex cannot be formed, and thus negligible SERS signals are detected. The degree of immunocomplex assembly and the corresponding SERS signals are positively correlated with the exosome concentration over a wide linear range of 40 to 4 × 107 particles per μL and the limit of detection is as low as 27 particles per μL. Consequently, a sensitive and simple strategy for detection of exosomes is successfully constructed. We believe that our biosensor has considerable potential as a convenient and highly sensitive quantification tool to detect exosomes in biological samples.

Graphical abstract: Highly sensitive detection of exosomes by SERS using gold nanostar@Raman reporter@nanoshell structures modified with a bivalent cholesterol-labeled DNA anchor

Supplementary files

Article information

Article type
Paper
Submitted
06 Jūn. 2018
Accepted
08 Sept. 2018
First published
10 Sept. 2018

Analyst, 2018,143, 4915-4922

Highly sensitive detection of exosomes by SERS using gold nanostar@Raman reporter@nanoshell structures modified with a bivalent cholesterol-labeled DNA anchor

Y. Tian, C. Ning, F. He, B. Yin and B. Ye, Analyst, 2018, 143, 4915 DOI: 10.1039/C8AN01041B

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