A Sweet Polydopamine Nanoplatform for Synergistic Combination of Targeted Chemo‐Photothermal Therapy

Inspired by sweet or sugar‐coated bullets that are used for medications in clinics and the structure and function of biological melanin, a novel kind of sweet polydopamine nanoparticles and their anticancer drug doxorubicin loaded counterparts are prepared, which integrate an active targeting function, photothermal therapy, and chemotherapy into one polymeric nanocarrier. The oxidative polymerization of lactosylated dopamine and/or with dopamine are performed under mild conditions and the resulting sweet nanoparticles are thoroughly characterized. When exposed to an 808 nm continuous‐wave diode laser, the magnitude of temperature elevation not only increases with the concentration of nanoparticles, but can also be tuned by the laser power density. The nanoparticles possess strong near infrared light absorption, high photothermal conversion efficiency, and good photostability. The nanoparticles present tunable binding with RCA₁₂₀ lectin and a targeting effect to HepG2 cells, confirmed by dynamic light scattering, turbidity analysis, MTT assay, and flow cytometry. Importantly, the sweet nanoparticles give the lowest IC₅₀ value of 11.67 μg mL⁻¹ for chemo‐photothermal therapy compared with 43.19 μg mL⁻¹ for single chemotherapy and 67.38 μg mL⁻¹ for photothermal therapy alone, demonstrating a good synergistic effect for the combination therapy.     

Remote‐Controllable Explosive Polymer Multilayer Tubes for Rapid Cancer Cell Killing

Gold nanoshell‐functionalized polymer multilayer tubes can be used as potent therapeutic agents for remote killing of cancer cells in a controlled manner due to the emerging pressure wave and tube fragments piercing the cell wall. The explosion is based on rapid evaporation of water inside the tubes caused by photothermal effects. The mechanism of explosion is presented in theory and experiment. The explosion of the tubes depends on the absorption coefficient and size of the gold nanoshells in the tubes, whereby the placement of the gold particles inside or outside of the tubes has no obvious effect on the explosive properties.

     

Reduced Graphene Oxide Functionalized with a Luminescent Rare‐Earth Complex for the Tracking and Photothermal Killing of Drug‐Resistant Bacteria

An antibacterial platform based on multifunctional reduced graphene oxide (rGO) that is responsive to near‐infrared (NIR) light has been constructed. By introducing a luminescent Eu³⁺ complex and vancomycin for bacteria tracking into one system, this platform could specifically recognize and light up bacteria. Antibacterial activity of this nanoscale construction under NIR illumination was investigated. Upon illumination with NIR light, this nanoscale architecture generates great heat locally, resulting in the death of drug‐resistant bacteria. These results indicate that the ability of this nanoscale platform to kill drug‐resistant bacteria has great potential for clinical pathogenic bacteria diagnosis and treatment.     

Enhancement of the 808 nm Photothermal Effect of Gold Nanorods by Thiol‐Induced Self‐Assembly

Gold (Au) nanomaterials are promising photothermal agents for the selective treatment of tumor cells owing to the strong capability to convert near‐infrared (NIR) irradiation into heat energy. One basic issue for practical photothermal therapy is the enhancement of photothermal effect in NIR region. Here, various low‐molecular‐weight thiols are applied to induce one‐dimensional (1D) self‐assembly of Au nanorods (NRs), which leads to the redshift of absorption peak towards NIR region. As a result, the 1D assembled Au NRs exhibit improved photothermal effect at 808 nm in comparison to unassembled Au NRs.     

载荷诱导骨生长的力学细胞生物学机制

骨骼的结构和功能在很大程度上依赖于其所处的力学环境,这一观点已被广为接受．自从Ｗｏｌｆｆ提出其著名的骨转换定律以来,骨生长与载荷间的关系一直是生物力学中一个重要的问题．大量的动物实验均证明二者之间存在明确的关联．然而,载荷诱导骨生长的力学细胞生物学（ｍｅｃｈａｎｏｃｙ－ｔｏｂｉｏｌｏｇｙ）机制仍很不清楚．十余年来体外培养骨骼细胞加载的研究为应力（应变）诱导骨生长提供了一个微观理论框架．目前认为,载荷诱导骨生长的过程可分为四个环节,即：力学耦联、生物化学耦联、胞间信号转导和效应细胞反应．详细阐述了这几个环节,并就今后的研究方向作一讨论．     

Mitochondria-Targeted Bovine Serum Albumin@Copper Sulfide Nanocomposites Conjugated with Rhodamine-110 Dye for an Enhanced Efficacy of Cancer Photothermal Therapy

Recently, mitochondria-targeted photothermal nanoagents demonstrated an improved therapeutic efficacy of cancer cells, compared with non-targeting ones. Herein, copper sulfide (CuS) nanoparticles are in situ synthesized via bovine serum albumin (BSA) templates to prepare photothermal BSA@CuS nanocomposites with high efficiency (42.0%) of photothermal conversion. Subsequently, rhodamine-110 (R) molecules are covalently conjugated with BSA@CuS nanocomposites to construct mitochondria-targeted R-BSA@CuS nanocomposites, which still retained 22.8% of photothermal conversion efficiency. Furthermore, as-prepared R-BSA@CuS nanocomposites can be efficiently internalized by human breast cancer (MCF-7) cells, and then specifically accumulated in their subcellular mitochondria, not lysosomes. Compared with non-targeting BSA@CuS nanocomposites, these mitochondria-targeted R-BSA@CuS nanocomposites show a significant enhancement (***p < 0.001) of their anticancer efficacy under the same near-infrared irradiation conditions, whose mechanism is further explored in details. Finally, these R-BSA@CuS nanocomposites can succeed in penetrating in 3D multicellular tumor spheroids composed of MCF-7 cells. And they also show a significant inhibition effect (**p < 0.01) on the growth of spheroids via photothermal therapy, in contrast to bare BSA@CuS nanocomposites under the same irradiation conditions. Therefore, these mitochondria-targeted and photothermal R-BSA@CuS nanocomposites have important potential applications on cancer photothermal therapy with an enhanced efficacy.     

近红外光热转换剂氧缺陷二氧化钼的制备及其在光热治疗中的应用

通过水热合成法,以五氯化钼（MoCl₅）为钼源,聚乙烯吡咯烷酮（PVP）为结构导向剂和还原剂,制备了二氧化钼（MoO₂）纳米颗粒,对纳米材料进行X射线粉末衍射（XRD）、透射电镜（TEM）、紫外可见近红外（UV-Vis-NIR）吸收光谱、X射线光电子能谱（XPS）、电子自旋共振谱（EPR）等表征,结果表明制备的MoO₂纳米颗粒粒度约18 nm,粒度均匀,具有丰富的氧缺陷,在650~1 100 nm的近红外区具有良好的光吸收能力。光热测试表明该材料100 μg·mL^-1的水溶液10 min内升温达31.5℃,光热转换率高达67.9%,并且具有优异的光热稳定性。细胞毒性实验表明低剂量的该纳米材料对细胞几乎没有毒性,且对肝癌细胞的光热杀伤效果明显。     

Core–Shell Bi2Se3@mSiO2‐PEG as a Multifunctional Drug‐Delivery Nanoplatform for Synergistic Thermo‐Chemotherapy with Infrared Thermal Imaging of Cancer Cells

Thermo‐chemotherapy combining photothermal therapy (PTT) with chemotherapy has become a potent approach for antitumor treatment. In this study, a multifunctional drug‐delivery nanoplatform based on polyethylene glycol (PEG)‐modified mesoporous silica‐coated bismuth selenide nanoparticles (referred to as Bi₂Se₃@mSiO₂‐PEG NPs) is developed for synergistic PTT and chemotherapy with infrared thermal (IRT) imaging of cancer cells. The product shows no/low cytotoxicity, strong near‐infrared (NIR) optical absorption, high photothermal conversion capacity, and stability. Utilizing the prominent photothermal effect, high‐contrast IRT imaging and efficient photothermal killing effect on cancer cells are achieved upon NIR laser irradiation. Moreover, the successful mesoporous silica coating of the Bi₂Se₃@mSiO₂‐PEG NPs cannot only largely improve the stability but also endow the NPs high drug loading capacity. As a proof‐of‐concept model, doxorubicin (DOX) is successfully loaded into the NPs with rather high loading capacity (≈50.0%) via the nanoprecipitation method. It is found that the DOX‐loaded NPs exhibit a bimodal on‐demand pH‐ and NIR‐responsive drug release property, and can realize effective intracellular drug delivery for chemotherapy. The synergistic thermo‐chemotherapy results in a significantly higher antitumor efficacy than either PTT or chemotherapy alone. The work reveals the great potential of such core–shell NPs as a multifunctional drug‐delivery nanosystem for thermo‐chemotherapy.     

Synergistic Effect of Photothermal Therapy and Chemotherapy Using Camptothecin‐Conjugated Gold Nanorods

A combinatorial treatment comprising thermal therapy and chemotherapy offers synergistic effects by inducing localized heat to targeted tumor sites and simultaneously delivering anticancer drugs to minimize systemic side effects and enhance the cytotoxic effect. In this study, a novel platform is developed for combining photothermal therapy and chemotherapy using drug‐conjugated gold nanorods (GNRs). Camptothecin (CPT), a model anticancer drug, is chemically conjugated onto GNRs through hydrolytic ester bonding. Upon near‐infrared (NIR) irradiation, localized heat from GNRs in target areas starts to destroy tissues and cells via photothermal therapy, and the elevated temperature accelerates hydrolysis of ester linkage, rapidly releasing drugs for chemotherapy. This combined NIR triggered thermal therapy and chemotherapy with CPT‐functionalized GNRs (CPT‐GNRs) presents a synergistic effect that has high efficacy in in vitro tests, thus providing a robust platform for efficient cancer treatments.