scholarly journals Current concepts in nanostructured contrast media development for in vivo photoacoustic imaging

2019 ◽  
Vol 7 (5) ◽  
pp. 1746-1775 ◽  
Author(s):  
Mirko Maturi ◽  
Erica Locatelli ◽  
Ilaria Monaco ◽  
Mauro Comes Franchini

To overcome the endogenous photoacoustic contrast arising from endogenous species, specific contrast agents need to be developed, allowing PAI to successfully identify targeted contrast in the range of wavelength in which the interference from the biomatrix is minimized.

Author(s):  
Maryam Hatamimoslehabadi ◽  
Stephanie Bellinger ◽  
Jonathan Rochford ◽  
Chandra S Yelleswarapu

2008 ◽  
Author(s):  
Ladislav Jankovic ◽  
Khalid Shahzad ◽  
Yao Wang ◽  
Michael Burcher ◽  
Frank-Detlef Scholle ◽  
...  

2017 ◽  
Vol 15 (21) ◽  
pp. 4531-4535 ◽  
Author(s):  
Yong Ni ◽  
Ravi Kumar Kannadorai ◽  
Sidney W.-K. Yu ◽  
Young-Tae Chang ◽  
Jishan Wu

Push–pull meso-ester BODIPYs with intense NIR absorption and good photo-stability were used for in vitro and in vivo photoacoustic imaging.


2013 ◽  
Vol 2 (2) ◽  
pp. 125-169 ◽  
Author(s):  
Quentin Le Trequesser ◽  
Hervé Seznec ◽  
Marie-Hélène Delville

AbstractThe successful development of nanomaterials illustrates the considerable interest in the development of new molecular probes for medical diagnosis and imaging. Substantial progress was made in the synthesis protocol and characterization of these materials, whereas toxicological issues are sometimes incomplete. Nanoparticle-based contrast agents (CAs) tend to become efficient tools for enhancing medical diagnostics and surgery for a wide range of imaging modalities. The multimodal nanoparticles (NPs) are much more efficient than the conventional molecular-scale CAs. They provide new abilities for in vivo detection and enhanced targeting efficiencies through longer circulation times, designed clearance pathways, and multiple binding capacities. Properly protected, they can safely be used for the fabrication of various functional systems with targeting properties, reduced toxicity, and proper removal from the body. This review mainly describes the advances in the development of mono- to multimodal NPs and their in vitro and in vivo relevant biomedical applications ranging from imaging and tracking to cancer treatment. Besides the specific applications for classical imaging (magnetic resonance imaging, positron emission tomography, computed tomography, ultrasound, and photoacoustic imaging), the less common imaging techniques such as terahertz molecular imaging (THMI) or ion beam analysis (IBA) are mentioned. The perspectives on the multimodal theranostic NPs and their potential for clinical advances are also mentioned.


2020 ◽  
Author(s):  
Juan Pablo Fuenzalida Werner ◽  
Yuanhui Huang ◽  
Kanuj Mishra ◽  
Robert Janowski ◽  
Paul Vetschera ◽  
...  

ABSTRACTOptoacoustic (photoacoustic) imaging has seen marked technological advances in detection and data analysis, but there is less progress in understanding the photophysics of optoacoustic signal generation of commonly used contrast agents, such as dyes and chromoproteins. This gap blocks the precise development of novel agents and the accurate analysis and interpretation of Multispectral Optoacoustic Tomography (MSOT) images. To close it, we developed a multimodal laser spectrometer (MLS) to enable the simultaneous measurement of optoacoustic, absorbance, and fluorescence spectra. MLS provides reproducible, high-quality optoacoustic (non-radiative) spectra by using correction and referencing workflow. Herein, we employ MLS to analyze several common dyes (Methylene Blue, Rhodamine 800, Alexa Fluor 750, IRDye 800CW and Indocyanine green) and proteins (sfGFP, mCherry, mKate, HcRed, iRFP720 and smURFP) and shed light on their internal conversion properties. Our data shows that the optical absorption spectra do not correlate with the optoacoustic spectra for the majority of the analytes. We determine that for dyes, the transition underlying the high energy shoulder, which mostly correlates with an aggregation state of the dyes, has significantly more optoacoustic signal generation efficiency than the monomer transition. Our analyses for proteins point to a favored vibrational relaxation and optoacoustic signal generation that stems from the neutral or zwitterionic chromophores. We were able to crystalize HcRed in its optoacoustic state, confirming the change isomerization respect to its fluorescence state. Such data is highly relevant for the engineering of tailored contrast agents for optoacoustic imaging. Furthermore, discrepancies between absorption and optoacoustic spectra underline the importance of correct spectral information as a prerequisite for the spectral-unmixing schemes that are often required for in vivo imaging. Finally, optoacoustic spectra of some of the most commonly used proteins and dyes in optical imaging, recorded on our MLS, reveal previously unknown photophysical characteristics, such as unobserved photo-switching behavior.


2021 ◽  
Vol 8 ◽  
Author(s):  
Guan Wang ◽  
Bo Wang ◽  
Tong Ye ◽  
Congcong Wang ◽  
Lili Guo ◽  
...  

Photoacoustic imaging (PAI) is a fast evolving imaging technology enabling in vivo imaging with high specificity and spatial resolution. However, due to strong background signals from various intrinsic chromospheres such as melanin, photoacoustic imaging of targeting objects labeled by contrast agents remain a challenge. The transient triplet differential (TTD) method has shown a significant potential for background-free photoacoustic imaging. Here, we develop a photoacoustic system using an ultrasonic semicircular ring array for transient triplet differential imaging. Pt(II) Octaethylporphine (PtOEP) and black ink are used as the contrast agent and the phantom of melanoma, respectively. Using the TTD method, we could remove the strong background signal from black ink. The ratio between contrast agent signal and background signal is increased to about 10 times the previous one. Our finding demonstrates the potential of the TTD method on molecular imaging for strong background removal.


2020 ◽  
Author(s):  
Shatadru Chakravarty ◽  
Jeremy Hix ◽  
Kaitlyn Wieweora ◽  
Maximilian Volk ◽  
Elizabeth Kenyon ◽  
...  

Here we describe the synthesis, characterization and in vitro and in vivo performance of a series of tantalum oxide (TaOx) based nanoparticles (NPs) for computed tomography (CT). Five distinct versions of 9-12 nm diameter silane coated TaOx nanocrystals (NCs) were fabricated by a sol-gel method with varying degrees of hydrophilicity and with or without fluorescence, with the highest reported Ta content to date (78%). Highly hydrophilic NCs were left bare and were evaluated in vivo in mice for micro-CT of full body vasculature, where following intravenous injection, TaOx NCs demonstrate high CT contrast, circulation in blood for ~ 3 h, and eventual accumulation in RES organs; and following injection locally in the mammary gland, where the full ductal tree structure can be clearly delineated. Partially hydrophilic NCs were encapsulated within mesoporous silica nanoparticles (MSNPs; TaOx@MSNPs) and hydrophobic NCs were encapsulated within poly(lactic-co-glycolic acid) (PLGA; TaOx@PLGA) NPs, serving as potential CT-imagable drug delivery vehicles. Bolus intramuscular injections of TaOx@PLGA NPs and TaOx@MSNPs to mimic the accumulation of NPs at a tumor site produce high signal enhancement in mice. In vitro studies on bare NCs and formuated NPs demonstrate high cytocompatibility and low dissolution of TaOx. This work solidifies that TaOx-based NPs are versatile contrast agents for CT.


2018 ◽  
Author(s):  
Danila Barskiy ◽  
Lucia Ke ◽  
Xingyang Li ◽  
Vincent Stevenson ◽  
Nevin Widarman ◽  
...  

<p>Hyperpolarization techniques based on the use of parahydrogen provide orders of magnitude signal enhancement for magnetic resonance spectroscopy and imaging. The main drawback limiting widespread applicability of parahydrogen-based techniques in biomedicine is the presence of organometallic compounds (the polarization transfer catalysts) in solution with hyperpolarized contrast agents. These catalysts are typically complexes of platinum-group metals and their administration in vivo should be avoided.</p> <p><br></p><p>Herein, we show how extraction of a hyperpolarized compound from an organic phase to an aqueous phase combined with a rapid (less than 10 seconds) Ir-based catalyst capture by metal scavenging agents can produce pure parahydrogen-based hyperpolarized contrast agents as demonstrated by high-resolution nuclear magnetic resonance (NMR) spectroscopy and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The presented methodology enables fast and efficient means of producing pure hyperpolarized aqueous solutions for biomedical and other uses.</p>


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