Lingxia Zhang

An anticancer drug delivery system based on surfactant-templated mesoporous silica nanoparticles.

Three types of surfactant-templated mesoporous silica nanoparticles (Surf@MSNs) of 150-660 nm in diameter were developed as anticancer drug delivery systems. The Surf@MSNs exhibit the high drug (surfactant) loading capacities, the sustained drug (surfactant) release profiles and the high and long-term anticancer efficacy. The effects of the Surf@MSNs concentration, the type of the contained surfactants and the incubation time on the cytotoxicity and proliferative activity of MCF-7 cells were evaluated. A common anticancer drug CPT-11 was also loaded into surfactant-free MSNs (CPT@MSNs) and used as a reference for estimating the anticancer efficacies of Surf@MSNs. Surfactant-extracted MSNs exhibited neglectable cytotoxicity to MCF-7 cell, and free surfactants exhibited higher cytotoxicity than free CPT-11 at the same concentration. The endocytosis enhanced the drug uptake by MCF-7 cells and the anticancer efficacies of Surf@MSNs and CPT@MSNs, and more surfactants would be released in a longer term, which led to the more significant enhancement of the cytotoxicity, than CPT-11 with the process of incubation. Among the investigated Surf@MSNs, CTAB-contained MSNs (CTAB@MSNs) show remarkably higher long-term anticancer efficacy than CPT-11-loaded surfactant-free MSNs (CPT@MSNs), even at very low concentrations of 2-15 microg mL(-1).

Nanocomposites from ordered mesoporous materials

The size distribution and dispersion of nanomaterials, in addition to their dimensions, are crucial for their performance. Ordered mesoporous materials (OMMs), due to their periodic and size-controllable pore channels (2–10 nm) and high surface areas, have been regarded as “a natural micro-reactor” to construct novel ordered and well dispersed nanocomposites with controlled size and size distribution. In this review, we overview the recent developments in nanomaterials preparation and properties from ordered mesoporous materials over the last five years, focusing on materials preparation methodology and special properties. Finally, the present and future research interests of nanocomposites from OMMs will also be discussed.

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.

Colloidal HPMO Nanoparticles: Silica‐Etching Chemistry Tailoring, Topological Transformation, and Nano‐Biomedical Applications

Hybridization produces the better: Colloidal hollow periodic mesoporous organosilica nanoparticles (HPMO NPs) with tunable compositions and highly hybridized nanostructures are successfully synthesized by a simple, easily scale-up but versatile silica-etching chemistry (alkaline or HF etching) for their applications in nano-fabrication and nano-medicine.

Brand new P-doped g-C3N4: enhanced photocatalytic activity for H2 evolution and Rhodamine B degradation under visible light

P-doped g-C3N4 has been successfully synthesized using hexachlorocyclotriphosphazene, a low cost and environmentally benign compound, as phosphorus source, and guanidiniumhydrochloride as g-C3N4 precursor, via a thermally induced copolymerization route. The obtained P-doped g-C3N4 showed excellent photocatalytic performance both in the photoreduction of H2O to produce H2 and the photodegradation of Rhodamine B (RhB). H2 evolution rate on modified g-C3N4 reached 50.6 μmol h−1, which is 2.9 times higher than that of the pure g-C3N4. RhB (10 mg L−1) was completely photodegraded within 10 min. The structure and texture properties of the P-doped g-C3N4 have been investigated in detail by XRD, FTIR, TEM, EDS and STEM. With the results of XPS and 31P NMR, a possible existing form of P atom in the framework g-C3N4 has been put forward. The introduction of a P atom significantly changes the electronic property of g-C3N4 and suppresses the recombination of photogenerated charge carriers, thus improving its photocatalytic performance.

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).

Double mesoporous silica shelled spherical/ellipsoidal nanostructures: Synthesis and hydrophilic/hydrophobic anticancer drug delivery

A general electrostatic interaction-based self-assembly strategy has been developed to synthesize various composite nanostructures with double mesoporous silica shells. The outer (second) mesoporous silica shell was coated on the surface of an inner (first) mesoporous silica nanostructure (nanosphere or nanolayer), which was templated by silane coupling agent (C18TMS), according to an electrostatic interaction mechanism between the negatively charged surface of inner mesoporous silica shell/sphere and positively charged cationic surfactant (C16TAB) for directing the second shell. The two adjacent shells directed by different pore-making agents show hierarchical pore size distributions and diverse pore structure orderings. This general strategy can be extended to synthesize a series of novel double-shelled mesoporous nanostructures with various morphologies, compositions and structures by altering the structural designing scheme in nanoscale (seven novel nanostructures created in this work). Importantly, the deposition of the second mesoporous shell on the surface of initial mesoporous nanostructures significantly increases the surface areas and pore volumes of as-prepared materials, which provides an alternative and versatile post-treatment approach to tune the key structural parameters of mesoporous nanomaterials. The double shelled hollow mesoporous silica spheres were found to be highly biocompatible, and were explored as both hydrophilic and hydrophobic anticancer drug delivery vehicles against cancer cells. The results show that the deposition of a second mesoporous silica shell could lead to a sustained release of a hydrophilic anticancer drug (irinotecan) from the carriers, and moreover, the double shelled mesoporous silica spheres exhibit high hydrophobic anticancer drug (docetaxel) loading capacity (15.24%), large amount uptake by cancer cells and enhanced anticancer efficiency, indicating the potential applications of synthesized nanoparticles in nanomedicine for cancer chemotherapy.

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.