Two-way magnetic resonance tuning and enhanced subtraction imaging for non-invasive and quantitative biological imaging

Abstract

Distance-dependent magnetic resonance tuning (MRET) technology enables the sensing and quantitative imaging of biological targets in vivo, with the advantage of deep tissue penetration and less interactions with the surroundings as compared to fluorescence-based Förster resonance energy transfer (FRET). However, applications of MRET technology in vivo are currently limited by the moderate contrast enhancement and stability of T 1 -based MRET probes. Here we report a new two-way magnetic resonance tuning (t-MRET) nanoprobe with dually activatable T 1 and T 2 magnetic resonance signals that is coupled with dual-contrast enhanced subtraction imaging (DESI). This integrated platform achieves substantially improved contrast enhancement with minimal background signal and can be used to quantitatively image molecular targets in tumours and to sensitively detect very small intracranial brain tumours in patient-derived xenograft models. The high tumour-to-normal tissue ratio offered by t-MRET in combination with DESI provides new opportunities for molecular diagnostics and image-guided biomedical applications.

Recent advances of high performance magnetic iron oxide nanoparticles: Controlled synthesis, properties tuning and cancer theranostics

“…Recently, Li et al. [ 166 ] prepared an interesting distance‐dependent plus two‐way magnetic resonance tuning (TMRET) nanoprobe, which encapsulates the T 1 and T 2 MRI agents in polymer micelles. The as‐formed nanoprobe responds to the tumor microenvironment, and quenches the T 1 and T 2 signals if they interact before reaching the tumor site.…”

“…However, if the contrast agent is released from the micelles, the dual‐ mode MR signals activate as soon as they interact with the tumor microenvironment. To improve the sensitivity of TMRET contrast, Li's group [ 166 ] developed a dual‐contrast enhanced subtraction imaging (DESI) technique for post‐processing and reconstruction of MRI. The DESI technique accurately detected tiny (0.75 mm 3 ) intracranial tumors in mice, and increased the MRI sensitivity by more than 10 times (see Figure 22).…”

“…Adapted with permission. [ 166 ] Copyright © 2020, The Author(s), under exclusive license to Springer Nature Limited…”

Phase controlled one-pot synthesis of heterostructured FePt–Fe3O4 nanocubes with excellent biocompatibility

“…Over the last few decades, there has been a growing research attention towards the various essential applications of magnetic nanoparticles (NPs), including catalysis, biological imaging, and bio-separations, immunodetection, high-density magnetic storage media, lab-on-a-chip device, and drug delivery system. [1][2][3][4][5][6][7][8] More recently, there has been a growing interest in the development of hybrid architectural magnetic NPs, a combination of two or more materials for advanced applications. [9][10][11][12][13][14] The hybrid NPs exhibit simultaneous multifunctional characteristics of each of the material's properties due to the combination of both materials in which the overlapping of the electronic bands of the adjacent material can even sometimes exhibit modied or unexpected excellent properties, which cannot be obtained by the individual material.…”

An Ester‐Substituted Semiconducting Polymer with Efficient Nonradiative Decay Enhances NIR‐II Photoacoustic Performance for Monitoring of Tumor Growth

“…Thus, based on the imaging enhancement to understand cancer progression, we have better ways to achieve the final goal of eradicating cancer [2] . Compared to the clinical imaging techniques, including magnetic resonance imaging, [3] positron emission tomography, [4] single photon emission computed tomography, [5] computed tomography, radiography [6] and ultrasound (US), the optical techniques such as fluorescent and photoacoustic (PA) imaging have been extremely appealing for biomedical and preclinical applications, [7] owing to their features of low‐cost, non‐radioactivity and easy operation. Recently, PA imaging has been an emerging modality, which has immense potential for detecting ultrasonic signal with optical excitation and can act as a portable standalone modality for imaging of blood vessels and other region of interest with or without contrast agents [8] .…”