Applications of the Photocatalytic and Photoacoustic Properties of Gold Nanorods in Contrast-Enhanced Ultrasound and Photoacoustic Imaging.

The applications of ultrasound imaging are often limited due to low contrast, which arises from the comparable acoustic impedance of normal tissues and disease sites. To improve the low contrast, we propose a contrast agent called gas-generating laser-activatable nanorods for contrast enhancement (GLANCE), which enhances ultrasound imaging contrast in two ways. First, GLANCE absorbs near-infrared lasers and generates nitrogen gas bubbles through the photocatalytic function of gold nanorods and photolysis of azide compounds.

Real-time monitoring of NIR-triggered drug release from phase-changeable nanodroplets by photoacoustic/ultrasound imaging.

Optical-responsive nanodroplets have recently been studied as a new mode of remotely controlled drug delivery. As a class of new emerging smart drug carriers, NIR-absorber-loaded perfluorocarbon nanodroplets can be converted into gas bubbles through laser stimulation, called optical droplet vaporization (ODV), which provides a potential strategy to deliver therapeutic agents to solid tumors on demand. However, there is a lack of suitable technologies to monitor these drug-loaded nanodroplet behaviors in vivo, and control the site and amount of drug released.

Characterizing a photoacoustic and fluorescence imaging platform for preclinical murine longitudinal studies.

Significance: To effectively study preclinical animal models, medical imaging technology must be developed with a high enough resolution and sensitivity to perform anatomical, functional, and molecular assessments. Photoacoustic (PA) tomography provides high resolution and specificity, and fluorescence (FL) molecular tomography provides high sensitivity; the combination of these imaging modes will enable a wide range of research applications to be studied in small animals.

Aim: We introduce and characterize a dual-modality PA and FL imaging platform using and phantom experiments.

Correction: photoacoustic image-guided tumor photothermal therapy and real-time temperature monitoring using a core-shell polypyrrole@CuS nanohybrid.

Correction for ' photoacoustic image-guided tumor photothermal therapy and real-time temperature monitoring using a core-shell polypyrrole@CuS nanohybrid' by Yang Cao , , 2022, , 12069-12076, https://doi.org/10.1039/D2NR02848D.

Photomagnetic Prussian blue nanocubes: Synthesis, characterization, and biomedical applications.

Nanoparticles play an important role in biomedicine. We have developed a method for size-controlled synthesis of photomagnetic Prussian blue nanocubes (PBNCs) using superparamagnetic iron oxide nanoparticles (SPIONs) as precursors. The developed PBNCs have magnetic and optical properties desired in many biomedical diagnostic and therapeutic applications.

Ultrasound-guided immunofunctional photoacoustic imaging for diagnosis of lymph node metastases.

Metastases, rather than primary tumors, determine mortality in the majority of cancer patients. A non-invasive immunofunctional imaging method was developed to detect sentinel lymph node (SLN) metastases using ultrasound-guided photoacoustic (USPA) imaging combined with glycol-chitosan-coated gold nanoparticles (GC-AuNPs) as an imaging contrast agent. GC-AuNPs, injected peritumorally into breast tumor-bearing mice, were taken up by immune cells, and subsequently transported to the SLN.

Photoacoustic Image-Guided Delivery of Plasmonic-Nanoparticle-Labeled Mesenchymal Stem Cells to the Spinal Cord.

Regenerative therapies using stem cells have great potential for treating neurodegenerative diseases and traumatic injuries in the spinal cord. In spite of significant research efforts, many therapies fail at the clinical phase. As stem cell technologies advance toward clinical use, there is a need for a minimally invasive, safe, affordable, and real-time imaging technique that allows for the accurate and safe monitoring of stem cell delivery in the operating room.

Tunable aggregation of gold-silica janus nanoparticles to enable contrast-enhanced multiwavelength photoacoustic imaging in vivo.

Photoacoustic imaging using exogenous contrast agents has emerged as a hybrid technique that enables the deep imaging of optical properties of tissues with high spatial resolution. The power of this imaging technique can be greatly enhanced by the use of contrast agents that absorb at near-infrared wavelengths and whose optical properties can be modulated in response to the local environment. We have designed contrast agents consisting of gold nanoparticles coated with anisotropic silica nanoshells.

Copper Sulfide Perfluorocarbon Nanodroplets as Clinically Relevant Photoacoustic/Ultrasound Imaging Agents.

We have developed laser-activated perfluorocarbon nanodroplets containing copper sulfide nanoparticles (CuS NPs) for contrast-enhanced ultrasound and photoacoustic imaging. As potential clinical contrast agents, CuS NPs have favorable properties including biocompatibility, biodegradability, and enhance contrast in photoacoustic images at clinically relevant depths. However, CuS NPs are not efficient optical absorbers when compared to plasmonic nanoparticles and therefore, contrast enhancement with CuS NPs is limited, requiring high concentrations to generate images with sufficient signal-to-noise ratio.

Monitoring/Imaging and Regenerative Agents for Enhancing Tissue Engineering Characterization and Therapies.

The past three decades have seen numerous advances in tissue engineering and regenerative medicine (TERM) therapies. However, despite the successes there is still much to be done before TERM therapies become commonplace in clinic. One of the main obstacles is the lack of knowledge regarding complex tissue engineering processes.