Development of Molecular Imaging Probe for Dual NIR/MR Imaging

Abstract

Imaging utilizing the near-infrared (NIR) light has attracted numerous attention due to the possibility in the deep tissue penetration as it can overcome the light scattering and absorption of tissue components. The ultraviolet (UV) unlikely penetrates the skin, while the visible (VIS) light can be scattered or absorbed by tissue components. This penetration likely improves as the wavelength shifts beyond 1000 nm region (also called NIR-II). Fat tissues are ascribed to the scattering of UV or VIS, while others such as water, melanin, hemoglobin are greatly attributed to absorbing light. Using NIR over 1000 nm (OTN-NIR) is currently considered as a critical approach for real-time dynamical visualization of the structure and functional features of tissues anatomically with refrained effects of fatty scattering and water absorption. However, the attempts to image anatomical structure by OTN-NIR is laborious and time-consuming. Then, for facile human applying, magnetic resonance imaging (MRI) is used as a guiding technique to localize the sites of interest. MRI is considered the most beneficial imaging technique without ionizing radiation which provides images with high resolution, preeminent tissue contrast. MRI also can visualize a large volume such as the human body to the few millimeter objects with great signal-to-noise ratio as well as contrastto-noise ratio. This review highlights the design of imaging probe for multimodal NIR/MR imaging, including the potential applications.

Er:Y2O3 and Nd:Y2O3 Nanoparticles: Synthesis, Pegylation, Characterization and Study of Their Luminescence Properties

“…In the field of Bioimaging, fluorescence imaging technology has become an indispensable method for monitoring changes in biochemical indicators and the appearance and development of biomarkers in living systems [1]. Since near-infrared (NIR) light is less absorbed and scattered in biological tissues, it can achieve high penetration efficiency, and thus fluorescence imaging technology has mainly focused on the NIR window [2][3][4][5]. In this context, lanthanide-doped yttrium oxide nanoparticles that can display selective upconversion properties, such as NIR to shorter NIR, visible (blue, green and red) and UV, are the candidates of election for in vivo bioimaging.…”

Internalization of Pegylated Er:Y2O3 Nanoparticles inside HCT-116 Cancer Cells: Implications for Imaging and Drug Delivery

“…Above all, rare earth ions have upconversion luminescence properties, whereby if irradiated in the far NIR they can emit in the near NIR or in the visible. Since NIR light has lower absorption and scattering in biological tissues, thus achieving high penetration efficiency, fluorescence imaging technology mainly makes use of the NIR window. − Thus, lanthanide-doped yttrium oxide nanoparticles, exhibiting upconversion properties, are prime candidates for in vivo bioimaging. ,, Y 2 O 3 nanoparticles, due to the chemical inertness of this material, are also characterized by a not high toxicity which makes them widely used in the biological field. − These systems, however, being “ceramic” are insoluble in an aqueous medium, and it is unlikely that they could be able to penetrate into the cells, as they are. It is therefore necessary to suitably functionalize them in order to reduce their toxicity and to use them for biological applications.…”