Imperial College London
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DrJamesChoi

Faculty of Engineering, Department of Bioengineering

Senior Lecturer
 
 
 
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Contact

 

+44 (0)20 7594 1777j.choi Website

 
 
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Location

 

RSM 4.06Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Morse:2020:10.7150/thno.42665,
author = {Morse, SV and Boltersdorf, T and Harriss, BI and Chan, TG and Baxan, N and Hee, Seok J and Pouliopoulos, AN and Choi, J and Long, NJ},
doi = {10.7150/thno.42665},
journal = {Theranostics},
pages = {2659--2674},
title = {Neuron labeling with rhodamine-conjugated Gd-based MRI contrast agents delivered to the brain via focused ultrasound},
url = {http://dx.doi.org/10.7150/thno.42665},
volume = {10},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Gadolinium-based magnetic resonance imaging contrast agents can provide information regarding neuronal function, provided that these agents can cross the neuronal cell membrane. Such contrast agents are normally restricted to extracellular domains, however, by attaching cationic fluorescent dyes, they can be made cell-permeable and allow for both optical and magnetic resonance detection. To reach neurons, these agents also need to cross the blood-brain barrier. Focused ultrasound combined with microbubbles has been shown to enhance the permeability of this barrier, allowing molecules into the brain non-invasively, locally and transiently. The goal of this study was to investigate whether combining fluorescent rhodamine with a gadolinium complex would form a dual-modal contrast agent that could label neurons in vivo when delivered to the mouse brain with focused ultrasound and microbubbles.Methods: Gadolinium complexes were combined with a fluorescent, cationic rhodamine unit to form probes with fluorescence and relaxivity properties suitable for in vivo applications. The left hemisphere of female C57bl/6 mice (8-10 weeks old; 19.07 ± 1.56 g; n = 16) was treated with ultrasound (centre frequency: 1 MHz, peak-negative pressure: 0.35 MPa, pulse length: 10 ms, repetition frequency: 0.5 Hz) while intravenously injecting SonoVue microbubbles and either the 1 kDa Gd(rhodamine-pip-DO3A) complex or a conventionally-used lysine-fixable Texas Red® 3 kDa dextran. The opposite right hemisphere was used as a non-treated control region. Brains were then extracted and either sectioned and imaged via fluorescence or confocal microscopy or imaged using a 9.4 T magnetic resonance imaging scanner. Brain slices were stained for neurons (NeuN), microglia (Iba1) and astrocytes (GFAP) to investigate the cellular localization of the probes.Results: Rhodamine fluorescence was detected in the left hemisphere of all ultrasound treated mice, while none was detected in the right contr
AU  - Morse,SV
AU  - Boltersdorf,T
AU  - Harriss,BI
AU  - Chan,TG
AU  - Baxan,N
AU  - Hee,Seok J
AU  - Pouliopoulos,AN
AU  - Choi,J
AU  - Long,NJ
DO  - 10.7150/thno.42665
EP  - 2674
PY  - 2020///
SN  - 1838-7640
SP  - 2659
TI  - Neuron labeling with rhodamine-conjugated Gd-based MRI contrast agents delivered to the brain via focused ultrasound
T2  - Theranostics
UR  - http://dx.doi.org/10.7150/thno.42665
UR  - http://hdl.handle.net/10044/1/76841
VL  - 10
ER  -
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