Synthesis and Characterization of GdVO4:Nd Near-Infrared Phosphors for Optical Time-Gated In Vivo Imaging.

Ewoud Cosaert,Daniela Meroni,Ben Nimmegeers,Tecla Carbonati,Dirk Poelman

doi:10.3390/ma13163564

Ewoud Cosaert, Daniela Meroni + Show 3 more

Open Access

https://doi.org/10.3390/ma13163564

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Abstract

Many medical imaging techniques use some form of ionizing radiation. This radiation is not only potentially harmful for the patient, but also for the medical personnel. An alternative imaging technique uses near-infrared (NIR) emitting luminescent particles as tracers. If the luminescent probes are excited inside the body, autofluorescence from the biological tissues is also induced. This problem can be circumvented by using time-gated imaging. Hereby, the light collection only starts when the fluorescence of the tissue has decayed. This requires particles showing both excitation and emission in the near-infrared and a long decay time so that they can be used in time-gated imaging. In this work, Nd-doped GdVO NIR emitting particles were prepared using solid state reaction. Particles could be efficiently excited at 808 nm, right in the first transparency window for biological tissues, emitted in the second transparency window at around 1064 nm, and showed a decay time of the order of 70 s, sufficiently long for time-gating. By using a Gd-containing host, these particles could be ideally suited for multimodal optical/magnetic imaging after size reduction and surface functionalization.

Highlights

There are many existing medical techniques to visualize the human body
This paper investigates the synthesis and properties of a Nd-doped phosphor, GdVO4
For the NH4 VO3 sample, V2 O5 was formed due to the high temperature according to the following reaction [13]: 2 NH4 VO3 → V2 O5 + 2 NH4 + H2 O

Summary

Introduction

There are many existing medical techniques to visualize the human body. Most of them use high energy photons. Depending on the type and functionality of the pharmakon, this will target a specific part of the body, like a tumor. The radiation of this radioactive molecule is harmful for the patient and everyone who comes close to the patient [1], especially when imaging is performed during surgery. Beside those invasive tools, there are imaging techniques that are harmless for the patient and surroundings, like MRI (magnetic resonance imaging) and ultrasound. Ultrasound is only suitable for imaging of organs at the surface of the body, and the image quality is much lower than that of other techniques

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