Issue 7, 2016

Visualization of in situ hydrogels by MRI in vivo

Abstract

It is of great interest to monitor implants in real-time using non-invasive detecting techniques in interventional therapies or tissue regeneration. In this study, MRI-visible hydrogels that are pH sensitive, injectable and self-healing were prepared based on chitosan and PEG. The macromolecular chelator of Gd(III), Ch–DTPA, was synthesized by functionalization of chitosan with diethylene triamine pentaacetic acid (DTPA). The PEG end-capped with aryl aldehyde, PEG-DA, was prepared as a crosslinker. Based on the Schiff's base reaction, the hydrogels can be obtained quickly just by mixing the aqueous solutions of Ch–DTPA and PEG-DA at ambient temperature. The gelating procedure is pH sensitive, and the hydrogels exhibit self-healing in an environment with a pH value of 4.5–5.3. The morphology of the lyophilized gel was observed by SEM. In vitro release behavior of the hydrogel was tested also using rhodamine B as a model drug. The MRI contrast enhancement effect of Gd(III)-binding hydrogels was investigated both in vitro and in vivo on rats. The results revealed that the hydrogels showed strong signals on T1-weighted MR images, and the hydrogels could always be detected before complete biodegradation. Combining the histology observation, the developed in situ hydrogels are of potential in the application of long-term reporting of implants by MRI.

Graphical abstract: Visualization of in situ hydrogels by MRI in vivo

Supplementary files

Article information

Article type
Paper
Submitted
23 Nov 2015
Accepted
12 Jan 2016
First published
13 Jan 2016

J. Mater. Chem. B, 2016,4, 1343-1353

Visualization of in situ hydrogels by MRI in vivo

J. Liu, K. Wang, J. Luan, Z. Wen, L. Wang, Z. Liu, G. Wu and R. Zhuo, J. Mater. Chem. B, 2016, 4, 1343 DOI: 10.1039/C5TB02459E

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