Photoacoustic Force-Guided Precise and Fast Delivery of Nanomedicine with Boosted Therapeutic Efficacy

Conjugated Polymeric Materials in Biological Imaging and Cancer Therapy

Conjugated polymers (CPs) have attracted much attention in the fields of chemistry, medicine, life science, and material science. Researchers have carried out a series of innovative researches and have made significant research progress regarding the unique photochemical and photophysical properties of CPs, expanding the application range of polymers. CPs are polymers formed by the conjugation of multiple repeating light-emitting units. Through precise control of their structure, functional molecules with different properties can be obtained. Fluorescence probes with different absorption and emission wavelengths can be obtained by changing the main chain structure. By modifying the side chain structure with water-soluble groups or selective recognition molecules, electrostatic interaction or specific binding with specific targets can be achieved; subsequently, the purpose of selective recognition can be achieved. This article reviews the research work of CPs in cell imaging, tumor diagnosis, and treatment in recent years, summarizes the latest progress in the application of CPs in imaging, tumor diagnosis, and treatment, and discusses the future development direction of CPs in cell imaging, tumor diagnosis, and treatment.

Fast Delivery of Multifunctional NIR-II Theranostic Nanoaggregates Enabled by the Photoinduced Thermoacoustic Process

Multifunctional nanoaggregates are widely used in cancer phototheranostics. However, it is challenging to construct their multifunctionality with a single component, and deliver them rapidly and efficiently without complex modifications. Herein, a NIR-absorbing small molecule named TBT-2(TP-DPA) is designed and certify its theranostic potentials. Then, their nanoaggregates, which are simply encapsulated by DSPE-PEG, demonstrate a photothermal efficiency of 51% while keeping a high photoluminescence quantum yield in the NIR region. Moreover, the nanoaggregates can be excited and delivered by an 808 nm pulse laser to solid tumors within only 40 min. The delivery efficiency and theranostic efficacy are better than that of the traditional enhanced permeability and retention (EPR) effect (generally longer than 24 hours). This platform is first termed as the photoinduced thermoacoustic (PTA) process, and confirm its application requires both NIR-responsive materials and pulse laser irradiation. This study not only inspires the design of multifunctional nanoaggregates, but also offers a feasible approach to their fast delivery. The platform reported here provides a promising prospect to boost the development of multifunctional theranostic drugs and maximize the efficacy of used medicines for their clinical applications.

Photoacoustic-triggered nanomedicine delivery to internal organs using a dual-wavelength laparoscope

Precise drug delivery for internal organs is always an important clinical issue. In this study, we developed a dual-wavelength optical resolution photoacoustic laparoscope, and achieved precise and efficient delivery of nanomedicine to multiple abdominal organs. The laparoscope integrated 532 and 820 nm light to map the vascular network, and visually deliver the nanoparticles to the targeted area using photoacoustic radiation force, respectively. To achieve endoscopic use, we employed a micro-electro-mechanical-system (MEMS) scanner to realize internal two-dimensional raster scanning of the optical beams. Using phantom experiments, the lateral resolutions were measured as 3.75 μm for 532 nm, and 5.25 μm for 820 nm, respectively. Besides, we demonstrated the feasibility of targeted drug delivery using mouse-ear tumor model, normal organs, and colon tumor model. All the experimental results suggested that this strategy can serve as a promising precise drug delivery method for the effective treatment of internal organ diseases.

Recent Advances in AIEgen-Based Photodynamic Therapy and Immunotherapy

Cancer, one of the leading causes of death, has seriously threatened public health. However, there is still a lack of effective treatments. Nowadays, photodynamic therapy (PDT), relying on photosensitizers to trigger the generation of reactive oxygen species (ROS) for killing cancer cells, has been emerging as a noninvasive anti-cancer strategy. To enhance the overall anti-cancer efficacy of PDT, various approaches including molecular design and combination with other therapeutic techniques have been proposed and implemented. Especially, photodynamic immunotherapy that can effectively evoke the body's immune response has attracted much attention. Recently, a class of photosensitizers with aggregation-induced emission (AIE) character have shown unique promises, taking advantage of their profound fluorescence and ROS-generating ability in the aggregation state. Despite the promising results demonstrated by several groups, the associated studies are few and the mechanism of such AIEgen-based photodynamic immunotherapy has not been fully understood. This review discusses the recent advances in the AIEgen-based enhanced PDT with a special focus on the AIE photosensitizers for photodynamic immunotherapy, aiming to inspire more opportunities for in-depth investigation of the working principles in this emerging anti-cancer approach.