High quality visualization of live mammalian embryo is an important requirement for studying fetal development. Photoacoustic tomography (PAT) and optical coherence tomography (OCT) are two advanced imaging modalities that have been utilized for embryonic imaging separately. However, high contrast, multiscale, and deep tissue imaging of embryos in vivo remains challenging. Here, we demonstrate multimodal contrast-enhanced imaging of live embryos by gold nanostar-meditated near-infrared I (NIR-I) PAT and near-infrared II (NIR-II) OCT. We investigate intravenous and intravaginal administration of gold nanostars, and significant enhancement of signal, image contrast, and imaging depth are achieved for both PAT and OCT. Our findings may facilitate detailed studies of the morphological and functional changes during embryonic development.
Guannan Zhang,Yongqiang Yang,Jing Shi,Xiaohong Yao,Weiyi Chen,Xiaochun Wei,Xiangyu Zhang,Paul K. Chu
Light-triggered therapy is a prospective method to combat implant-associated infection but near-infrared I (NIR-I) light has insufficient penetrating ability in tissues and local hyperthermia induced by the photothermal treatment may destroy surrounding healthy tissues. Herein, a near-infrared II (NIR-II) phototherapy system composed of upconversion elements doped titanium dioxide nanorods (TiO 2 NRs)/curcumin (Cur)/hyaluronic acid (HA)/bone morphogenetic protein-2 (BMP-2) is designed for biomedical titanium and demonstrated to overcome the above hurdles simultaneously. Incorporation of F, Yb, and Ho not only improves the photocatalytic ability, but also renders the implants with the upconversion capability, so that the NRs can generate enough reactive oxygen species (ROS) when irradiated by the NIR-II laser . Furthermore, the combined actions of quorum sensing inhibitors, ROS, and physical puncture by NRs eliminate Staphylococcus aureus biofilms on titanium rapidly at a mild temperature of 45 °C by only requiring irradiation with the 1060 nm laser for only 15 min in vitro and in vivo . The presence of Cur mitigates the immune response and BMP-2 improves osteogenic differentiation , thus accelerating new bone formation. This low-temperature NIR-II light-triggered antibacterial platform has large potential in combating deep-tissue infection in clinical applications.
危险品化学品经营许可证（带存储）