A5078864574- Photoacoustic and Ultrasonic Imaging
- Thermography and Photoacoustic Techniques
- Nanoplatforms for cancer theranostics
- Optical Imaging and Spectroscopy Techniques
- Extracellular vesicles in disease
- Ultrasound and Hyperthermia Applications
- Optical Coherence Tomography Applications
- Ultrasound Imaging and Elastography
- Advanced MEMS and NEMS Technologies
- Advanced Sensor and Energy Harvesting Materials
- Spectroscopy Techniques in Biomedical and Chemical Research
- Advanced Surface Polishing Techniques
- Micro and Nano Robotics
- Image Processing Techniques and Applications
- Modular Robots and Swarm Intelligence
- Luminescence and Fluorescent Materials
- Random lasers and scattering media
- Photodynamic Therapy Research Studies
- Soft Robotics and Applications
- Thermal Regulation in Medicine
- Advanced Fluorescence Microscopy Techniques
- Image Enhancement Techniques
- Perovskite Materials and Applications
- Nanofabrication and Lithography Techniques
- Molecular Communication and Nanonetworks
City University of Hong Kong
2016-2025
City University of Hong Kong, Shenzhen Research Institute
2018-2025
Washington University in St. Louis
2011-2020
City University of Seattle
2018-2019
Kowloon Hospital
2018
Optica
2011-2017
Tsinghua University
2005-2016
University of Toronto
2006-2010
Abstract Extensive recent progress has been made on the design and applications of organic photothermal agents for biomedical because their excellent biocompatibility comparing with inorganic materials. One major hurdle further development is rarity high‐performance materials in second near‐infrared (NIR‐II) window, which allows deep tissue penetration causes minimized side effects. Up till now, there have few reported NIR‐II‐active conversion efficiencies are relatively low. Herein, optical...
Label-free functional imaging of single red blood cells (RBCs) in vivo holds the key to uncovering fundamental mechanism oxygen metabolism cells. To this end, we developed single-RBC photoacoustic flowoxigraphy (FOG), which can image delivery from flowing RBCs with millisecond-scale temporal resolution and micrometer-scale spatial resolution. Using intrinsic optical absorption contrast oxyhemoglobin (HbO2) deoxyhemoglobin (HbR), FOG allows label-free imaging. Multiple parameters, including...
Despite the great success achieved by photoactivated chemotherapy, eradicating deep tumors using external sources with high tissue penetration depth remains a challenge. Here, we present cyaninplatin, paradigm of Pt(IV) anticancer prodrug that can be activated ultrasound in precise and spatiotemporally controllable manner. Upon sono-activation, mitochondria-accumulated cyaninplatin exhibits strengthened mitochondrial DNA damage cell killing efficiency, overcomes drug resistance as...
We developed a photoacoustic imaging system that has real-time capability with optical resolution. The is capable of scanning at 20 Hz over 9 mm range and up to 40 1 range. A focused laser beam provides lateral resolution 3.4 μm as measured in an optically nonscattering medium. Flows micrometer-sized carbon particles or whole blood silicone tube individual red cells (RBCs) mouse ear capillaries were also imaged real time, demonstrating the image highly dynamic processes vivo micrometer-scale
Super-resolution microscopy techniques - capable of overcoming the diffraction limit light have opened new opportunities to explore subcellular structures and dynamics not resolvable in conventional far-field microscopy. However, relying on staining with exogenous fluorescent markers, these can sometimes introduce undesired artifacts image, mainly due large tagging agent sizes insufficient or variable labeling densities. By contrast, use endogenous pigments allows imaging intrinsic...
By offering images with high spatial resolution and unique optical absorption contrast, optical-resolution photoacoustic microscopy (OR-PAM) has gained increasing attention in biomedical research. Recent developments OR-PAM have improved its imaging speed, but to sacrifice either the detection sensitivity or field of view both. We developed a wide-field fast-scanning by using water-immersible microelectromechanical systems (MEMS) scanning mirror (MEMS-OR-PAM). In MEMS-OR-PAM, acoustic beams...
The temperature-dependent property of the Grueneisen parameter has been employed in photoacoustic imaging mainly to measure tissue temperature. Here we explore this using a different approach and develop relaxation microscopy (GR-PAM), technique that images nonradiative absorption with confocal optical resolution. GR-PAM sequentially delivers two identical laser pulses microsecond-scale time delay. first pulse generates signal thermally tags in-focus absorbers. When second excites tagged...
Photoacoustic (PA) imaging and tracking of stem cells plays an important role in the real-time assessment cell-based therapies. Nevertheless, limitations conventional inorganic PA contrast agents narrow range excitation wavelength first near-infrared (NIR-I) window hamper applications living subjects. Herein, we report design synthesis a second (NIR-II) absorptive organic semiconducting polymer (OSP)-based nanoprobe (OSPN+) for cells. Comparison studies biological tissue show that NIR-II...
Three-dimensional (3D) optical imaging of whole biological organs with microscopic resolution has remained a challenge. Most versions such techniques require special preparation the tissue specimen. Here we demonstrate microtomy-assisted photoacoustic microscopy (mPAM) mouse brains and other organs, which automatically acquires serial distortion-free registration-free images endogenous absorption contrasts. Without staining or clearing, mPAM generates micrometer-resolution 3D paraffin-...
Micro/nanorobots have long been expected to reach all parts of the human body through blood vessels for medical treatment or surgery. However, in current stage, it is still challenging drive a microrobot viscous media at high speed and difficult observe shape position single once enters bloodstream. Here, we propose new micro-rocket robot an all-optic driving imaging system that can actuate track with microscale resolution. To achieve force, engineer rocket-like triple-tube structure. Owing...
Subdiffraction optical microscopy allows the imaging of cellular and subcellular structures with a resolution finer than diffraction limit. Here, combining absorption-based photoacoustic effect intensity-dependent photobleaching effect, we demonstrate simple method for subdiffraction both fluorescent nonfluorescent samples. Our is based on double-excitation process, where first excitation pulse partially inhomogeneously bleaches molecules in diffraction-limited volume, thus biasing signal...
Precise diagnosis and effective treatment of gliomas still remain a huge challenge. Photoacoustic-guided photothermal therapy (PTT) has unique advantages over conventional techniques for brain tumor theranostics, but existing nanoagents photoacoustic imaging (PAI)-guided PTT are mainly organic small molecules or inorganic nanoparticles, which have the limitations poor photostability biocompatibility. Besides, restricted absorption in first near-infrared window (NIR-I) most compromises their...
Precise delivery of therapeutic cells to the desired site in vivo is an emerging and promising cellular therapy precision medicine. This paper presents development a magnet-driven image-guided degradable microrobot that can precisely deliver engineered stem for orthotopic liver tumor treatment. The employs burr-like porous sphere structure made with synthesized composite fulfill degradability, mechanical strength, magnetic actuation capability simultaneously. be spontaneously released from...
Abstract It remains highly challenging to identify small molecule‐based photothermal agents with a high conversion efficiency (PTCE). Herein, we adopt double bond‐based molecular motor concept develop new class of break the current design bottleneck. As double‐bond is twisted by strong intramolecular charge transfer (TICT) upon irradiation, excited can deactivate non‐radiatively through conical intersection (CI) internal conversion, which called photoinduced nonadiabatic decay. Such possess...
Photoacoustic agents have been of vital importance for improving the imaging contrast and reliability against self-interference from endogenous substances. Herein, we synthesized a series thiadiazoloquinoxaline (TQ)-based semiconducting polymers (SPs) with broad absorption covering NIR-I to NIR-II regions. Among them, excited s-BDT-TQE, repeating unit SPs, shows large dihedral angle narrow adiabatic energy as well low radiative decay, attributing its strongly electron-deficient...
We report wide-field polygon-scanning functional OR-PAM that for the first time achieves 1-MHz A-line rate of oxygen saturation in vivo. address two technical challenges. The is a dual-wavelength pulsed laser has sufficient pulse energy and ultrafast wavelength switching. second imaging probe fast scanning speed, large field view, great sensitivity. system offers B-scan 477.5 Hz 12-mm range volumetric ∼1 over 12 × 5 mm
Acquiring ultrafast and high spectral resolution optical images is key to measure transient physical or chemical processes, such as photon propagation, plasma dynamics, femtosecond reactions. At a trillion Hz frame rate, most imaging modalities can acquire only limited number of frames. Here, we present compressed spectral-temporal (CUST) photographic technique, enabling both an ultrahigh rate 3.85 large number. We demonstrate that CUST photography records 60 frames, precisely recording...
Optical-resolution photoacoustic microscopy (OR-PAM) has been developed for anatomical, functional, and molecular imaging but usually requires multiple scanning different contrasts. We present five-wavelength OR-PAM simultaneous of hemoglobin concentration, oxygen saturation, blood flow speed, lymphatic vessels in single raster scanning. develop a pulsed laser via stimulated Raman scattering. The five wavelengths, i.e., 532, 545, 558, 570, 620 / 640 nm, are temporally separated by several...