Trials in developing a nanoscale material for extravascular contrast-enhanced ultrasound targeting hepatocellular carcinoma

Background Medical imaging is an important approach for the diagnosis of hepatocellular carcinoma (HCC), a common life threaten disease, however, the diagnostic efficiency is still not optimal. Developing a novel method to improve diagnosis is necessary. The aim of this project was to formulate a material that can combine with GPC3 of HCC for targeted enhanced ultrasound. Methods A material of sulfur hexafluoride (SF6) filled liposome microbubbles and conjugated with synthesized peptide (LSPMbs) was prepared and assessed in vitro and vivo. Liposome microbubbles were made of DPPC, DPPG, DSPE-PEG2000,and SF6, using thin film method to form shell, followed filling SF6, and conjugating peptide. A carbodiimide method was used for covalent conjugation of peptide to LSMbs. Results The prepared LSPMbs appeared round shaped, with size of 380.9 ± 176.5 nm, and Zeta potential of −51.4 ± 10.4mV. LSPMbs showed high affinity to Huh-7 cells in vitro, presented good enhanced ultrasound effects, did not show cytotoxicity, and did not exhibit targeted fluorescence and enhanced ultrasound in animal xenograft tumors. Conclusion Extravascular contrast-enhanced ultrasound targeted GPC3 on HCC may not be realized, and the reason may be that targeted contrast agents of microbubbles are hard to access and accumulate in the tumor stroma and matrix.

Scoping Review of Targeted Ultrasound Contrast Agents in the Detection of Myocardial Ischemia

Objective: A systematic search was conducted to categorize targeted ultrasound contrast agents used in the detection of myocardial ischemia. Methods: The search identified 14 primary research articles published from 2000 to August 2019 that fulfilled the selection criteria. All studies were conducted in animal models ranging from mice to rhesus monkeys, with the most common targets being P-selectin and E-selectin. Results: These studies show that targeted ultrasound contrast agents produced greater signal enhancement in regions with prolonged ischemia and maintained enhancement hours after reperfusion. Conclusion: This review identified gaps in the literature, such as a need for comparative studies among different molecular markers and between current standard of care with the use of targeted contrast agents in cardiac ultrasound.

Targeted Contrast Agents for Molecular MRI

Molecular magnetic resonance imaging (MRI) provides information non-invasively at cellular and molecular levels, for both early diagnosis and monitoring therapeutic follow-up. This imaging technique requires the development of a new class of contrast agents, which signal changes (typically becomes enhanced) when in presence of the cellular or molecular process to be evaluated. Even if molecular MRI has had a prominent role in the advances in medicine over the past two decades, the large majority of the developed probes to date are still in preclinical level, or eventually in phase I or II clinical trials. The development of novel imaging probes is an emergent active research domain. This review focuses on gadolinium-based specific-targeted contrast agents, providing rational design considerations and examples of the strategies recently reported in the literature.

Molecular imaging modalities using nanoprobes for cancer diagnosis

Molecular imaging modalities are used for different type of cancers detection and diagnosis. In recent few years, there has been an increased focus on developing novel nanoparticles as new imaging contrast agents for early detection of cancer. The aim of this review article is to summarize molecular imaging technologies accompanying with using nanoparticles to improve potential imaging for cancer detection and hence valuable therapy in the future. Nanoprobes are rapidly becoming potentially transformative tools on cancer diagnostics for a wide range of imaging modalities such as CT, MRI, SPECT, PET, Ultrasound and Optical imaging. The study results seen in the recent literature are provided and discussed the diagnostic performance of imaging modalities for cancer diagnosis and their future directions. With knowledge of the correlation between the application of nanoparticles and molecular imaging modalities and with the development of targeted contrast agents or nanoprobes, they may provide better cancer diagnosis in the future.

Affibody-functionalized Ag2S quantum dots for photoacoustic imaging of epidermal growth factor receptor overexpressed tumors

Photoacoustic imaging (PAI) is a new and attractive imaging modality, and it has strong potential for application in the early detection of tumors through the use of optically absorbing targeted contrast agents.