Meiying Wu

Hollow mesoporous organosilica nanoparticles: a generic intelligent framework-hybridization approach for biomedicine.

Chemical construction of molecularly organic-inorganic hybrid hollow mesoporous organosilica nanoparticles (HMONs) with silsesquioxane framework is expected to substantially improve their therapeutic performance and enhance the biological effects beneficial for biomedicine. In this work, we report on a simple, controllable, and versatile chemical homology principle to synthesize multiple-hybridized HMONs with varied functional organic groups homogeneously incorporated into the framework (up to quintuple hybridizations). As a paradigm, the hybridization of physiologically active thioether groups with triple distinctive disulfide bonds can endow HMONs with unique intrinsic reducing/acidic- and external high intensity focused ultrasound (HIFU)-responsive drug-releasing performances, improved biological effects (e.g., lowered hemolytic effect and improved histocompatibility), and enhanced ultrasonography behavior. The doxorubicin-loaded HMONs with concurrent thioether and phenylene hybridization exhibit drastically enhanced therapeutic efficiency against cancer growth and metastasis, as demonstrated both in vitro and in vivo.

Break‐up of Two‐Dimensional MnO2 Nanosheets Promotes Ultrasensitive pH‐Triggered Theranostics of Cancer

Chemically exfoliated two-dimensional MnO2 nanosheets are successfully modified with amino-polyethylene glycol as a theranostic platform for ultrasensitive stimuli-responsive theranostics of cancer. The highly dispersed MnO2 nanosheets exhibit a unique break-up in the mildly acidic microenvironment of tumor tissues, which could substantially enhance their in vitro and in vivo performances in T1 -weighted magnetic resonance imaging. Such a pH-triggered breaking-up behavior could further promote the fast release of loaded anticancer drugs for concurrent pH-responsive drug release and circumvent the multidrug resistance of cancer cells.

Highly selective CO2 photoreduction to CO over g-C3N4/Bi2WO6 composites under visible light

CO2 is highly stable and therefore extremely difficult to be reduced at room temperature even by photocatalysis. Herein, a series of g-C3N4/Bi2WO6 composites have been synthesized through a facile in situ hydrothermal approach, which demonstrated greatly enhanced response to visible light, and consequently a remarkably enhanced CO2 selective photoreduction to CO. The g-C3N4 content and synthesis parameters of these composites have been tuned to obtain the optimized photocatalytic activity with a peak CO production rate of 5.19 μmol g−1 h−1 under visible light irradiation at room temperature, which was 22 and 6.4 times that on pure g-C3N4 and Bi2WO6, respectively. Based on the matched band energy potentials between g-C3N4 and Bi2WO6 in the synthesized composites, a possible Z-scheme mechanism, which features a significantly promoted separation of photo-generated carriers under visible light irradiation by the composites, has been proposed to account for the distinctive CO2 photoreduction performance.

Large-Pore Ultrasmall Mesoporous Organosilica Nanoparticles: Micelle/Precursor Co-templating Assembly and Nuclear-Targeted Gene Delivery

A novel micelle/precursor co-templating assembly strategy is successfully developed to synthesize large-pore ultrasmall mesoporous organosilica nanoparticles (MONs). Furthermore, elaborately designed MONs with a cell-penetrating peptide (TAT) (MONs-PTAT) are constructed for highly efficient intranuclear gene delivery. They exhibit a high loading capacity, improved protection for the loaded gene, and enhanced transfection efficiencies of EGFP plasmid (pEGFP).

Colloidal RBC‐Shaped, Hydrophilic, and Hollow Mesoporous Carbon Nanocapsules for Highly Efficient Biomedical Engineering

Dr. Y. Chen, [+] Dr. M. Y. Wu, Prof. Dr. H. R. Chen, Dr. Z. Shu, Dr. J. Wang, Prof. Dr. L. X. Zhang, Prof. Dr. J. L. Shi State Laboratory of High Performance Ceramics and Superfi ne Microstructures Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 , P. R. China E-mail: hrchen@mail.sic.ac.cn; jlshi@sunm.shcnc.ac.cn Dr. P. F. Xu, [+] Dr. Q. S. Meng, Prof. Dr. Y. P. Li Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 , P. R. China E-mail: ypli@mail.shcnc.ac.cn

Large Pore‐Sized Hollow Mesoporous Organosilica for Redox‐Responsive Gene Delivery and Synergistic Cancer Chemotherapy

A stability-difference-selective bond-breakage strategy for the fabrication of largepore-sized hollow mesoporous organosilica nanoparticles (HMONs) is successfully developed. Moreover, surfacefunctionalized HMONs are successfully constructed to simultaneously deliver P-gp modulator siRNA and anticancer drug doxorubicin to reverse the multidrug resistance of cancer cells.

A Prussian Blue‐Based Core–Shell Hollow‐Structured Mesoporous Nanoparticle as a Smart Theranostic Agent with Ultrahigh pH‐Responsive Longitudinal Relaxivity

Novel core-shell hollow mesoporous Prussian blue @ Mn-containing Prussian blue analogue (HMPB@MnPBA) nanoparticles, designated as HMPB-Mn) as an intelligent theranostic nanoagent, are successfully constructed by coating a similarly crystal-structured MnPBA onto HMPB. This can be used as a pH-responsive T1 -weighted magnetic resonance imaging contrast agent with ultrahigh longitudinal relaxivity (r1 = 7.43 m m(-1) s(-1) ), and achieves the real-time monitoring of drug release.

A salt-assisted acid etching strategy for hollow mesoporous silica/organosilica for pH-responsive drug and gene co-delivery

A salt-assisted acid etching (SAAE) strategy has been developed to construct rattle/hollow mesoporous silica/organosilica nanovehicles (R/HMSVs or R/HMOVs), which settles the drawbacks of traditional silica etching approaches, such as undesirable by-products, by alkaline etching and strong corrosion of the HF etching process. The hollow structure and phenylene-bridged framework of HMOVs were found to be responsible for the high cargo-loading capacity and pH-responsive drug releasing behavior, respectively, based on the special cargo-framework interaction. Especially, the molecularly organic-inorganic hybrid HMOVs have been, for the first time, successfully engineered to concurrently deliver anticancer drugs and P-gp-associated shRNA molecules for enhancing the intracellular drug concentrations and reversing the multidrug resistance (MDR) of cancer cells. On the basis of this special SAAE strategy, a wide range of mesoporous silica-based hollow nanostructures are anticipated to be synthesized to satisfy the strict requirements in various nano-catalytic and biomedical applications.

Tumor vascular-targeted co-delivery of anti-angiogenesis and chemotherapeutic agents by mesoporous silica nanoparticle-based drug delivery system for synergetic therapy of tumor.

To overcome the drawback of drug non-selectivity in traditional chemotherapy, the construction of multifunctional targeting drug delivery systems is one of the most effective and prevailing approaches. The intratumoral anti-angiogenesis and the tumor cell-killing are two basic approaches in fighting tumors. Herein we report a novel tumor vascular-targeting multidrug delivery system using mesoporous silica nanoparticles as carrier to co-load an antiangiogenic agent (combretastatin A4) and a chemotherapeutic drug (doxorubicin) and conjugate with targeting molecules (iRGD peptide) for combined anti-angiogenesis and chemotherapy. Such a dual-loaded drug delivery system is capable of delivering the two agents at tumor vasculature and then within tumors through a differentiated drug release strategy, which consequently results in greatly improved antitumor efficacy at a very low doxorubicin dose of 1.5 mg/kg. The fast release of the antiangiogenic agent at tumor vasculatures led to the disruption of vascular structure and had a synergetic effect with the chemotherapeutic drug slowly released in the following delivery of chemotherapeutic drug into tumors.

Endogenous Catalytic Generation of O2 Bubbles for In Situ Ultrasound-Guided High Intensity Focused Ultrasound Ablation

High intensity focused ultrasound (HIFU) surgery generally suffers from poor precision and low efficiency in clinical application, especially for cancer therapy. Herein, a multiscale hybrid catalytic nanoreactor (catalase@MONs, abbreviated as C@M) has been developed as a tumor-sensitive contrast and synergistic agent (C&SA) for ultrasound-guided HIFU cancer surgery, by integrating dendritic-structured mesoporous organosilica nanoparticles (MONs) and catalase immobilized in the large open pore channels of MONs. Such a hybrid nanoreactor exhibited sensitive catalytic activity toward H2O2, facilitating the continuous O2 gas generation in a relatively mild manner even if incubated with 10 μM H2O2, which finally led to enhanced ablation in the tissue-mimicking PAA gel model after HIFU exposure mainly resulting from intensified cavitation effect. The C@M nanoparticles could be accumulated within the H2O2-enriched tumor region through enhanced permeability and retention effect, enabling durable contrast enhancement of ultrasound imaging, and highly efficient tumor ablation under relatively low power of HIFU exposure in vivo. Very different from the traditional perfluorocarbon-based C&SA, such an on-demand catalytic nanoreactor could realize the accurate positioning of tumor without HIFU prestimulation and efficient HIFU ablation with a much safer power output, which is highly desired in clinical HIFU application.