Fluorescent tomography has been hindered by poor tissue penetration and weak signal which results in poor spatial resolution and quantification accuracy. Recently, it has been reported that activatable temperature responsive fluorescent probes which respond to focused ultrasound heating can improve the resolution and quantification of fluorescent tomography in deep tissue. This has lead to a new imaging modality, "Temperature-modulated fluorescent tomography." This technique relies on activatable thermo-sensitive fluorescent nanocapsules for whose fluorescence quantum efficiency is temperature dependent. Within a 4-5° C temperature range, the fluorescent signal increase more than 10-fold. In this molecular probe, Indocyanine Green (ICG) is encapsulated inside the core of a thermo-reversible pluronic micelle. Here we show the fluorescence response and temperature range of the nanocapsules which have been optimized for a higher temperature range to be used for in vivo animal imaging. We report on the feasibility of these temperature-sensitive reversible nanocapsules for in vivo applications by studying the pharmacokinetics in a subcutaneous mouse tumor model in vivo.

Date Published: 12 March 2015
PDF: 6 pages
Proc. SPIE 9339, Reporters, Markers, Dyes, Nanoparticles, and Molecular Probes for Biomedical Applications VII, 93390C (12 March 2015); doi: 10.1117/12.2080189

Published in SPIE Proceedings Vol. 9339:
Reporters, Markers, Dyes, Nanoparticles, and Molecular Probes for Biomedical Applications VII
Samuel Achilefu; Ramesh Raghavachari, Editor(s)