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Metal-organic framework (MOF)-derived materials have attracted increasing interest and show promising catalytic performances in many fields. Intensive efforts have been focused on the structure design and metal-site integration in MOF-derived catalysts. However, the key catalytic processes related with the metal sites in MOF-derived catalysts that dominate the electrocatalytic performance still remain obscure. Herein, we show a neglected but critical issue in the pyrolytic synthesis of MOF-derived catalysts: the coupled evolution of dual sites, that is, metallic sites and single-atom metal sites. The identification of active sites of single-atom sites from the visible particles has been elucidated through the combined X-ray spectroscopic, electron microscopic, and electrochemical studies. Interestingly, after a total removal of metallic cobalt sites, catalysts with purified single-atom metal sites show no faltering activity for either the oxygen reduction reaction (ORR) or hydrogen evolution reaction (HER), while significantly enhanced ORR selectivity is achieved; this reveals the dominant activity and selectivity contribution from single-atom electrocatalysis. The insight of the coupled evolution of dual sites and the as-demonstrated dual-site decoupling strategies open up a new routine for the design and synthesis of MOF-derived catalysts with the optimized single-atom electrocatalysis towards various electrochemical reactions.

Lowering power output and radiation time during radiofrequency (RF) ablation is still a challenge. Although it is documented that metal-based magnetothermal conversion and microbubbles-based inertial cavitation have been tried to overcome above issues, disputed toxicity and poor magnetothermal conversion efficiency for metal-based nanoparticles and violent but transient cavitation for microbubbles are inappropriate for enhancing RF ablation. In this report, a strategy, i.e., continuous cavitation, has been proposed, and solid menthol-encapsulated poly lactide-glycolide acid (PLGA) nanocapsules have been constructed, as a proof of concept, to validate the role of such a continuous cavitation principle in continuously enhancing RF ablation. The synthesized PLGA-based nanocapsules can respond to RF to generate menthol bubbles via distinctive radiofrequency solidoid vaporization (RSV) process, meanwhile significantly enhance ultrasound imaging for HeLa solid tumor, and further facilitate RF ablation via the continuous cavitation, as systematically demonstrated both in vitro and in vivo. Importantly, this RSV strategy can overcome drawbacks and limitations of acoustic droplet vaporization (ADV) and optical droplet vaporization (ODV), and will probably find broad applications in further cancer theranostics.

A 3D assembly of crumpled nitrogen-doped carbon nanosheets with hierarchical frameworks and encased ultrafine iron carbide nanoparticles on the subunits was constructed via a template-free bottom-up self-assembly strategy. The optimized structure design and catalytic-site integration endow the electrocatalyst with outstanding PH-universal ORR performance, serving as a good alternative for the Pt/C catalyst.

High-intensity focused ultrasound (HIFU) is deemed to be a promising noninvasive therapeutic modality for cancers as well as non-neoplastic diseases. However, the accuracy of the technique in the diagnosis and treatment of tumors remains unsatisfactory. HIFU, when combined with multifunctional synergistic agents (SAs), has the potential to be of greater diagnostic and therapeutic efficacy. Here we describe a smart and multifunctional hollow mesoporous Prussian blue (HMPBs) theranostic nanoplatform, the hollow structure of which is capable of encapsulating doxorubicin (DOX) and perfluorohexane (HMPBs-DOX/PFH). In vitro and in vivo studies validated that HMPBs-DOX/PFH can be used as an amplifiable dual-mode imaging contrast agent, which can simultaneously enhance ultrasound (US) and photoacoustic (PA) imaging for guiding and monitoring tumor therapy. When exposed to HIFU, this versatile HMPBs-DOX/PFH agent could increase the cavitation effect and use lower HIFU intensity to achieve coagulative necrosis. Furthermore, it significantly accelerated the release of DOX thereby enhancing chemotherapeutic efficacy and avoiding systemic side effects of the drug. Such a novel theranostic nanoplatform is expected to integrate dual-mode guided imaging with greater therapeutic efficacy and fewer side effects and is very promising for the noninvasive synergistic tumor therapy.

Magnetic hyperthermia ablation is a new and minimally invasive modality for localized tumor removal. However, an inadequate ablation dosage can leave a residual tumor or cause a variety of complications. In addition, commonly used magnetic nanoparticles can easily escape from the tumor tissue, which present potential safety problems. In this study, a smart phase transitional and injectable implant based on biocompatible poly lactic-co-glycolic acid (PLGA) implant incorporating magnetic material (Fe powder) and anti-cancer drug (doxorubicin (DOX)) was developed. The magnetic-induced hyperthermia and release efficiency of DOX were evaluated in vitro. Drug release can be controlled under external alternating current magnetic field (AMF). The results of the in vivo tumor therapeutic efficacy showed that when exposed to external AMF, this smart injectable DOX/PLGA-Fe implant could converse magnetic energy into heat and accelerate the release of DOX, which leads to increasing the temperature to achieve tumor coagulative necrosis and accelerating the release of DOX to enhance residual tumor apoptosis. Furthermore, there was no leakage of magnetic material, as demonstrated using real-time ultrasound (US) and computerized tomography (CT) imaging, realizing the guidance and monitoring of tumor therapy. In conclusion, this smart phase transitional and injectable implant DOX/PLGA-Fe has the ability to improve the efficiency of this newly developed minimally invasive magnetic ablation of tumor treatment technique, and will provide a new avenue of developing minimally invasive synergistic tumor therapy.

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.

Despite great efforts having been devoted to the design of multimodal imaging probe, almost all design principles of nanotheranostic agents subordinate to simple assemblies of building blocks, resulting in complex preparation process and discounted ability, that is, 1 + 1 < 2. In this report, a novel design strategy, marriage of structure design and composition design that can maximize imaging ability of each building block, ultimately achieving 1 + 1 ≥ 2, has been established. Moreover, a high-efficient ultrasound (US) & MR & CT trimodal contrast agent acts as model to instantiate this design strategy, wherein nanoparticles-induced nonlinear scattering and rattle-type structure-induced double scattering enhancing US imaging, and uniform distribution of Mn(2+) paramagentic centers and "core-satellite" structure of Au atoms favoring enhanced MR imaging and CT imaging, respectively have been validated, achieving optimization of structure design. Importantly, the selected components, silica, Au and MnO are endowed with excellent biocompatibility, displaying the marriage strategy of composition design with aforementioned structure optimization. In in vivo evaluations, such a biocompatible trimodal probe is demonstrated of excellent performance in intensifying CT, MR and US imaging in vivo, especially after positively charged modification by PEI promoting more probes retained in tumor. More importantly, as a universal design strategy, the involved principles in constructing such a US&MR&CT trimodal imaging probe promise great potentials in guiding designs of other materials-based multimodal imaging probe.

Ultrasound (US) imaging in combination with US contrast agents (UCAs) is a powerful tool in the modern biomedical field because of its high spatial resolution, easy access to patients and minimum invasiveness. The microbubble-based UCAs have been widely used in clinical diagnosis; however, they are only limited to the blood pool imaging and not applicable to the tissue-penetrated imaging due to their large particle size and structural instability. Inorganic nanoparticles (NPs), such as silica, gold and FexOy, featured with both satisfactory echogenic properties and structural stability have the potential to be used as a new generation of UCAs. In this review, we present the most recent progresses in the tailored construction of inorganic UCAs and their biomedical applications in the US imaging-involved fields. Firstly, the typical inorganic NPs with different structures including solid, hollow and multiple-layer forms will be comprehensively introduced in terms of their structure design, physicochemical property, US imaging mechanism and diverse applications; secondly, the recent progress in exploring the gas-generating inorganic NP system for US imaging purpose will be reviewed, and these intelligent UCAs are multifunctional for simultaneous US imaging and disease therapy; thirdly, several nanocomposite platforms newly constructed by combining inorganic UCAs with other functional components will be presented and discussed. These multifunctional NPs are capable of further enhancing the imaging resolution by providing more comprehensive anatomical information simultaneously. Last but not the least, the design criteria for developing promising UCAs to satisfy both clinical demands and optimized US imaging capability will be discussed and summarized in this review.

An easy one-step hydrothermal process has been developed for the first time for the synthesis of hierarchically structured zeolites (HSZs) using a single micropore template of tetrapropylammonium hydroxide. Compared with conventional constructive dual-templating synthesis and destructive post-demetallation methods, this two-in-one process reduces the mass of porogens required and consequent air pollution by combustion of the template, and simplifies the synthesis. The resultant HSZs were characterized by X-ray diffraction, N2 adsorption, scanning electron microscopy, transmission electron microscopy, X-ray fluorescence, 27Al nuclear magnetic resonance, and NH3 temperature programmed desorption. The resultant HSZs with uniform shuttle-type morphology showed high hydrothermal stability and excellent catalytic activity with prolonged life-time in the model reaction of 1,3,5-triisopropylbenzene cracking. A “nucleation/growth-demetallation/recrystallization” mechanism was proposed, which is featured with the integration of zeolite crystallization/growth and basic etching into one hydrothermal process for HSZs production.

A kind of multifunctional perfluoropentane (PFP) and ultrasmall Cu2−xS nanodots (u-Cu2−xS NDs) co-incorporated liposome (PFP@u-Cu2−xS NDs@liposome) nanocomposite has been facilely and successfully synthesized for enhanced ultrasound/infrared thermal/photoacoustic multimodal imaging and photothermal therapy upon near infrared (NIR) laser irradiation. Such a liposome-based nanocomposite possesses a number of advantages, such as high dispersity and stability, excellent biocompatibility, small particle size ( in vitro investigations demonstrate that the as-synthesized PFP@ u-Cu2−xS NDs@liposome nanocomposite is capable of enhancing the contrasts of ultrasound/infrared thermal/photoacoustic multimodal imaging, and substantially improving the photothermal therapeutic efficacy. This novel liposome-based theranostic nanoplatform shows great potentials in the future cancer diagnosis and therapy.

Inorganic nanocarriers have shown their high performance in disease theranostics in preclinical animal models and further great prospects for clinical translation. However, their dissatisfactory biodegradability and pre-drug leakage with nonspecificity to lesion sites significantly hinders the possible clinical translation. To solve these two critical issues, a framework-engineering strategy is introduced to simultaneously achieve enhanced biodegradability and controllable drug releasing, based on the mostly explored mesoporous silica-based nanosystems. The framework of mesoporous silica is engineered by direct Mg doping via a generic dissolution and regrowth approach, and it can transform into the easy biodegradation of magnesium silicate nanocarriers with simultaneous on-demand drug release. Such magnesium silicate nanocarriers can respond to the mild acidic environment of tumor tissue, causing the fast breaking up and biodegradation of the silica framework. More interesting, the released Mg2+ can further activate Mg2+ -dependent DNAzyme on the surface of hollow mesoporous magnesium silicate nanoparticles (HMMSNs) to cleave the RNA-based gatekeeper, which further accelerates the release of loaded anticancer drugs. Therefore, enhanced anticancer efficiency of chemotherapeutic drugs assisted by the biodegradable intelligent HMMSNs is achieved. The high biocompatibility of nanocarriers and biodegradation products is demonstrated and can be easily excreted via feces and urine guaranteeing their further clinical translation.

To overcome the toxicity of chemotherapy, increasing attention has been paid to local drug delivery systems (DDSs). pH-Sensitive hydrogels have emerged as promising DDS materials in the biomedical field due to their remarkable characteristics. However, the pH environment in tumor varies from person to person, which makes the applicability of systems based on pH challenging. In this study, we developed a contractible hydroxypropyl methyl cellulose (HPMC)/Fe3O4 hydrogel with dual-response pH and magnetic properties aiming to overcome the limitations of pH-sensitive hydrogel drug delivery systems and further increase their efficiency in tumor therapy. The HPMC/Fe3O4 hydrogel could act as a drug delivery system that combines pH-sensitive triggering and magnetic dual-response drug release for synergistic chemo-magnetic hyperthermia therapy. The drug delivery profile of the HPMC/Fe3O4/doxorubicin hydrochloride (DOX) hydrogel was determined in vitro and revealed a remarkable pH-sensitive performance. After synergistic chemo-magnetic hyperthermia treatment, mice with 4T1 breast cancer xenografts recovered without any recurrence or metastasis, demonstrating the synergistic effect of chemotherapy and magnetic hyperthermia therapy. Meanwhile, reduced toxicity and superior anticancer effects were achieved due to the combined effect of the pH and magnetic hyperthermia response properties. This study demonstrated the high efficacy and low toxicity of the improved design of HPMC/Fe3O4 for drug delivery, which may provide a promising approach for the application of chemo-magnetic hyperthermia cancer therapy.

The integration of efficient imaging for diagnosis and synergistic tumor therapy into a single-component nanoplatform is much promising for high efficacy tumor treatment but still in a great challenge. Herein, a smart and versatile nanotheranostic platform based on hollow mesoporous Prussian blue nanoparticles (HMPBs) with perfluoropentane (PFP) and doxorubicin (DOX) inside, has been designed, for the first time, to achieve the distinct in vivo synergistic chemo-thermal tumor therapy and synchronous diagnosis and monitoring by ultrasound (US)/photoacoustic (PA) dual mode imaging. The prepared HMPBs show excellent photothermal conversion properties with large molar extinction coefficient (≈1.2 × 1011m−1 cm−1) and extremely high photothermal conversion efficiency (41.4%). Such a novel theranostic nanoplatform is expected to overcome the inevitable tumor recurrence and metastasis resulting from the inhomogeneous ablation of single thermal therapy, which will find a promising prospect in the application of noninvasive cancer therapy.

The efficient removal of low-concentration nitric oxide at room temperature from a semi-closed space is becoming a crucial but challenging issue in the context of increasingly serious air pollution. A novel nanoflower-like weak crystallization manganese oxide (WMO) has been synthesized via a facile and scalable strategy for low-concentration nitric oxide oxidation at room temperature. The prepared WMO shows the nanoflower-like morphology with abundant water molecules and Mn vacancies inside. Such WMO could easily adsorb NO and quickly convert it into NO2via catalytic oxidization. Herein, the weak crystallization structure and the presence of Mn vacancies are identified to be mainly responsible for the adsorption and catalytic oxidation of NO. More importantly, it shows much longer lifetime in a moist stream of simulated feed gas than that under dry conditions, which can be attributed to the relative stability of the catalyst with hydrated surfaces. Comparative DFT-calculations are performed to reveal the catalytic effect of Mn-vacancies and hydrated surfaces in reducing the reaction barriers of rate-determining steps.

Two-dimensional transition metal dichalcogenides, particularly MoS2 nanosheets, have been deemed as a novel category of NIR photothermal transducing agent. Herein, an efficient and versatile one-pot solvothermal synthesis based on "bottom-up" strategy has been, for the first time, proposed for the controlled synthesis of PEGylated MoS2 nanosheets by using a novel "integrated" precursor containing both Mo and S elements. This facile but unique PEG-mediated solvothermal procedure endowed MoS2 nanosheets with controlled size, increased crystallinity and excellent colloidal stability. The photothermal performance of nanosheets was optimized via modulating the particulate size and surface PEGylation. PEGylated MoS2 nanosheets with desired photothermal conversion performance and excellent colloidal and photothermal stability were further utilized for highly efficient photothermal therapy of cancer in a tumor-bearing mouse xenograft. Without showing observable in vitro and in vivo hemolysis, coagulation and toxicity, the optimized MoS2-PEG nanosheets showed promising in vitro and in vivo anti-cancer efficacy.

A hierarchically porous zeolite beta has been designed via a facile combined surfactant-assisted hydrothermal treatment and subsequent alkali etching approach. High contents of the Cu and Mn species were then highly dispersed into the as-synthesized hierarchically porous zeolite beta. The prepared composite catalyst exhibits highly active, stable and recyclable catalytic performances for soot oxidation, and extraordinarily low T50 (260 °C) and T90 (300 °C) values can be achieved in the presence of NO. A synergetic catalytic effect between valence-varied active species Cun+ and Mnn+ has been proposed, which features the promoted generations of highly active oxygen species O−/O2− and active intermediate NO2. In addition, the obtained catalyst shows an excellent water resistance performance in soot oxidation due to the hydrophobic crystalline zeolite framework and the interaction between soot and water vapor.

As a highly biocompatible NIR dye, indocyanine green (ICG) has been widely explored for cancer treatment due to its various energy level transition pathways upon NIR light excitation simultaneously, which leads to different theranostic effects ( eg. Photoacoustic (PA) and fluorescence imaging (FL), photodynamic and photothermal therapy (PDT&PTT)). However, the theranostic efficiency of ICG is restricted intrinsically, owing to the competitive relationship of its co-existing imaging and therapeutic effect. Moreover, the extrinsic hypoxia nature of tumor further limits its therapeutic effect, especially for the oxygen-dependent PDT. Herein, perfluorooctyl bromide (PFOB), another biocompatible chemical, was integrated with ICG in a nanoliposome structure via a facile two-step emulsion method. Such an ICG&PFOB co-loaded nanoliposomes (LIP-PFOB-ICG) realized computed tomography (CT) contrast imaging in vivo, providing better anatomical information of tumor in comparison to ICG enabled PA and FL imaging. More importantly, LIP-PFOB-ICG inhibited MDA-MB-231 tumor growth completely via intravenous injection through enhanced PDT&PTT synergistic therapy due to the excellent oxygen carrying ability of PFOB, which effectively attenuated tumor hypoxia , improved the efficiency of collisional energy transfer between ICG and oxygen and reduced the expression of heat shock protein (HSP). As expected, the introduction of PFOB within nanoliposomes with ICG has augmented the theranostic effect of ICG comprehensively, which makes this simple biocompatible liposome-based nanoagent a potential candidate for clinical imaging guided phototherapy of cancer.

A precious metal-free cathode catalyst, mesoporous Ba

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 (CSA) 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 H

The introduction of active transition metal sites (TMSs) in carbon enables the synthesis of noble-metal-free electrocatalysts for clean energy conversion applications; however, there are often multiple existing forms of TMSs, which are of different natures and catalytic models. Regulating the evolution of distinctive TMSs is highly desirable but remains challenging to date. Anions, as essential elements involved in the synthesis, have been totally neglected previously in the construction of TMSs. Herein, the effects of anions on the creation of different types of TMSs are investigated for the first time. It is found that the active cobalt-nitrogen sites tend to be selectively constructed on the surface of N-doped carbon by using chloride, while metallic cobalt nanoparticles encased in protective graphite layers are the dominant forms of cobalt species with nitrate ions. The obtained catalysts demonstrate cobalt-sites-dependent activity for oxygen reduction reaction and hydrogen evolution reaction in acidic media. The remarkably enhanced catalytic activities approaching that of benchmark Pt/C in an acidic medium have been obtained on the catalyst dominated with cobalt-nitrogen sites, confirmed by the advanced spectroscopic characterization. This finding demonstrates a general paradigm of anion-regulated evolution of distinctive TMSs, providing a new pathway for enhancing performances of various targeted reactions related with TMSs.

Alzheimer's disease (AD) is a prevalent chronic neurodegenerative disease. However, to date, none of the developed drug candidates targeting at a single therapeutic target of AD have achieved success in clinical trials. Herein, we proposed a hypothesis of hollow manganese Prussian white nanocapsules (HMPWCs)-mediated attenuation of Tau-related pathology and alleviation of cognitive decline via simultaneously alleviating neuroinflammation, scavenging reactive oxygen species, and reducing hyperphosphorylated Tau proteins. The HMPWCs self-assemblied with manganese Prussian white analogue and bovine serum albumin via a novel biomimetic mineralization present good biocompatibility, variable valence states, and low oxidation-reduction potential. They own the outstanding capabilities of relieving oxidative stress, inhibiting Tau neuropathology, and counteracting neuroinflammation, which could be used to treat Tau-related AD-like neurodegeneration. Importantly, they can also attenuate the cognitive impairments of Tau-related AD-like rats without significant side effects. This research takes the advantages of catalytic chemistry, nanomedicine and specific neurodegenerative microenvironment together, providing an alternative efficient treatment strategy for Tau-related neurodegeneration diseases, such as AD, Pick's disease, frontotemporal dementia, Creutzfeldt-Jakob Disease and progressive supranuclear palsy.

Mesoporous silica nanoparticles (MSNs) have been extensively applied as a promising carrier in biomedical application due to their excellent structure with tunable function. Based on the fact that the surfactant trimethoxyoctadecylsilane (C18TMS) could present different on/off states in different solvents, herein, an intelligent “on/off” switching strategy of site-specific co-loading MnOx and Ce6 into MSNs was proposed for the first time. The multifunctional theranostic nanoplatform, i.e., Ce6/MnOx@HMSNs-PEG (CMHP), shows a sensitive longitudinal relaxation signal to the over-expressed hydrogen peroxide (H2O2) and weak acidic pH in the tumor microenvironment (TME). Furthermore, MnOx component could react with H2O2 in TME to generate O2, which enable to relieve tumorous hypoxia and afterwards accelerate the generation of singlet oxygen (1O2) upon laser irradiation when combined with Ce6. Both in vitro and in vivo results confirm that this constructed nanosystem can be applied to MRI-guided sufficient photodynamic therapy (PDT) with reduced side-effects.

Co 3 O 4 nanoflowers with high surface areas were synthesized with a facile template-free ultrasonic process and showed high performance on the removal of low-concentration (10 ppm) NO at room temperature. By doping Mg 2 + in the Co 3 O 4 nanoflowers, improved performances of about 9 h for above 50% NO removal were obtained.

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.

A hierarchically porous RuO2–CuO/(Al–ZrO2) nanocomposite, with RuO2 and CuO nanocrystals being homogeneously dispersed in the hierarchically porous structure of Al-doped ZrO2 (Al–ZrO2), has been developed by a hydrothermal and wet impregnation method for efficient ammonia-selective catalytic oxidation (SCO) applications. The microstructures of the RuO2–CuO/Al–ZrO2 nanocomposites were characterized by XRD, TEM, FESEM, EDX elemental mapping, and N2 sorption. XPS analysis and H2-TPR results indicate that the hierarchically porous RuO2–CuO/Al–ZrO2 composites possess a large number of oxygen vacancies and surface catalytic active sites, which endows the composite with high catalytic activity and N2 selectivity for NH3 oxidation. NH3 complete oxidization has been achieved at 195 °C with 100% N2 selectivity over an obtained RuO2–CuO/Al–ZrO2 composite at RuO/CuO = 1:1 (weight rate). The high efficiency of hierarchically porous RuO2–CuO/Al–ZrO2 nanocomposites for ammonia SCO reaction has been attributed to the syn...

The CdS and Pt NPs have been homogeneously anchored and highly dispersed into the mesopore channels of hierarchically porous zeolite Beta by a facile successional two-step pore modification technology. A highly efficient and stable H 2 evolution of 3.09 mmol/h/g catalyst has been successfully achieved by using the prepared novel catalyst under sunlight irradiation. It is believed that the highly dispersive CdS and Pt NPs and the synergetic catalytic effect between them, as well as the interaction between CdS species and zeolite matrix, contribute to the enhanced separation and transfer of photoelectrons and holes, and therefore improving its electrochemical properties and H 2 evolution rate. Besides, and this novel hierarchical pore structure of zeolite Beta serving as a host can effectively protect CdS NPs from photocorrosion, thus exhibiting high stability in the catalytic system.

Construction of multifunctional stimuli-responsive nanosystems intelligently responsive to inner physiological and/or external irradiations based on nanobiotechnology can enable the on-demand drug release and improved diagnostic imaging to mitigate the side-effects of anticancer drugs and enhance the diagnostic/therapeutic outcome simultaneously. Here, a triple-functional stimuli-responsive nanosystem based on the co-integration of superparamagnetic Fe3O4 and paramagnetic MnOx nanoparticles (NPs) onto exfoliated graphene oxide (GO) nanosheets by a novel and efficient double redox strategy (DRS) is reported. Aromatic anticancer drug molecules can interact with GO nanosheets through supramolecular π stacking to achieve high drug loading capacity and pH-responsive drug releasing performance. The integrated MnOx NPs can disintegrate in mild acidic and reduction environment to realize the highly efficient pH-responsive and reduction-triggered T1-weighted magnetic resonance imaging (MRI). Superparamagnetic Fe3O4 NPs can not only function as the T2-weighted contrast agents for MRI, but also response to the external magnetic field for magnetic hyperthermia against cancer. Importantly, the constructed biocompatible GO-based nanoplatform can inhibit the metastasis of cancer cells by downregulating the expression of metastasis-related proteins, and anticancer drug-loaded carrier can significantly reverse the multidrug resistance (MDR) of cancer cells. A triple-functional biocompatible stimuli-responsive nanosystem based on the functionalized nanographene oxides is developed by a novel and efficient double redox strategy. This elaborately designed nanographene oxide-based nanoplatform exhibits the unique triple stimuli-responsivenesses for biomedical engineering, including pH-responsive drug release to inhibit the metastasis and reverse the multidrug resistance of cancer cells, pH-/redox-responsive magnetic resonance imaging and magnetic field-responsive hyperthermia of cancer.

Nitrogen-doped multiwall carbon nanotubes (N-MWCNTs) have been synthesized by a co-pyrolysis route of iron(II) phthalocyanine (FePc) loaded and PEO20–PPO70–PEO20 retained in mesoporous silica. In this process, FePc was used as both Fe-catalyst, carbon and nitrogen sources, and P123-containing mesoporous silica was employed as both the substrate and carbon seeds/source for the growth of N-MWCNTs. The obtained samples have well-defined morphology and graphitic structure, and show high electrochemical catalytic activity and stability for oxygen reduction reaction, attributing to the highly graphitic structure and the pyridinic-type nitrogen in the N-MWCNTs. The power density of a single fuel cell using N-MWCNT as cathodic catalyst was measured to be 67.7% of that of a standard single cell using 40% Pt/C as cathodic catalyst.

A useful and interesting unconventional phenomenon of Pd nanoparticle formation, i.e., significantly inhibited particle growth at elevated temperatures, has been observed for the first time by growing Pd nanoparticles on a type of nonreactor, amino group-functionalized hollow mesoporous silica nanoparticles (amino-HMSNs). Such an unconventional effect is evidenced to be a competitive result between temperature-dependent coordination and reduction action of amino groups on the shell of HMSNs based on a series of experiments of probing the coordination and reduction capability of the amino groups to a Pd precursor K2PdCl6. A possible mechanism has been proposed to demonstrate and clarify the unconventional growth of Pd nanoparticles on the shell of amino-HMSNs. The as-synthesized Pd nanoparticles on the amino-HMSNs, therefore, show a tunable temperature-dependent small size range (

Superparamagnetic mesoporous zeolite microspheres with a large mesopore size of 13 nm and a high surface area of 382 m(2) g(-1) were synthesized for the capacious enrichment of proteins and enzymes. A high degree of ovalbumin immobilization was obtained (491 mg g(-1)) at pH 6, which is nearly twice that previously reported in the literature.

Hierarchically porous carbon monoliths (HPCMs) with both ordered hexagonal mesoporosity and three-dimensionally connected macroporosity were synthesized via a simple and time-saving hydrothermal process followed by a nanocasting pathway. These monoliths have high macropore volumes and specific surface areas, strong hydrophobicity, low densities and regular shapes. Importantly, these HPCMs showed excellent performance in cleaning/recycling spilled oils or organic solvents with high adsorption capacity, rate, stability, and reusability, and in adsorbing bilirubin with high adsorption capacity, blood compatibility and durability in plasma as well. The adsorption of oil was based on the dispersion interaction between gasoline molecules and the carbon basal planes of HPCMs, while the isotherm of bilirubin adsorption on the optimized HPCMs and the corresponding kinetic data were found better fitted by Langmuir adsorption model and pseudo-second-order kinetic model, respectively.

A novel upconversion luminescence transparent glass has been successfully synthesized from Er 3+ /Yb 3+ co-doped zeolite powder by Spark Plasma Sintering (SPS) method through the order–disorder transition process. XRD was used to detect the order–disorder transition process of each phase after SPS. These zeolite-derived silica glasses showed enhanced upconversion luminescence under the excitation of 980 nm diode laser, which was caused by the change of phonon energy according to the results of Raman spectrum, and the corresponding energy transfer mechanism was also discussed in detail.

A novel multifunctional nanotheranostic agent with targeting, redox-responsive ultrasound imaging and ultrasound imaging-guided high-intensity focused ultrasound (HIFU) therapy (MSNC-PEG-HA(SS)-PFH, abbreviated as MPH(SS)-PFH) capabilities is developed. The redox-responsive guest molecule release and ultrasound imaging functions can be both integrated in such a "smart" theranostic agent, which is accomplished by the redox-triggered transition from the crosslinking state to retrocrosslinking state of the grafted polyethylene glycol-disulfide hyaluronic acid molecules on the particle surface when reaching a reducing environment in vitro. More importantly, under the tailored ultrasound imaging guiding, in vivo Hela tumor-bearing nude mice can be thoroughly and spatial-accurately ablated during HIFU therapy, due to the targeted accumulation, responsive ultrasound imaging guidance and the synergistic ablation functions of nanotheranostic agent MPH(SS)-PFH in the tumors. This novel multifunctional nano-platform can serve as a promising candidate for further studies on oncology therapy, due to its high stability, responsive and indicative ultrasound imaging of tumors, and enhanced HIFU therapeutic efficiency and spatial accuracy under ultrasound-guidance.

Biocompatible inorganic material-based nanosystems provide a novel choice to effectively circumvent the intrinsic drawbacks of traditional organic materials in biomedical applications, especially in overcoming the multidrug resistance (MDR) of cancer cells due to their unique structural and compositional characteristics, for example, high stability, large surface area, tunable compositions, abundant physicochemical multifunctionalities, and specific biological behaviors. In this review, we focus on the recent developments in the construction of inorganic nanoparticles-based drug codelivery nanosystems (mesoporous SiO2, Fe3O4, Au, Ag, quantum dots, carbon nanotubes, graphene oxide, LDH, etc.) to efficiently circumvent the MDR of cancer cells, including the well-known codelivery of small molecular anticancer drug/macromolecular therapeutic gene and codelivery of small molecular chemosensitizer/anticancer drug, and very recently explored codelivery of targeting ligands/anticancer drug, codelivery of energy/anticancer drug, and codelivery of contrast agent for diagnostic imaging and anticancer drug. The unsolved issues, future developments, and potential clinical translations of these codelivery nanosystems are also discussed. These elaborately designed biocompatible inorganic materials-based nanosystems offer an unprecedented opportunity and show the encouraging bright future for overcoming the MDR of tumors in clinic personalized medicine and the pharmaceutical industry.

Colloidal hollow mesoporous silica nanoparticles (HMSNs) are aspecial type of silica-based nanomaterials with penetrating mesopore channels on their shells. HMSNs exhibit unique structural characteristics useful for diverse applications: Firstly, the hollow interiors can function as reservoirs for enhanced loading of guest molecules, or as nanoreactors for the growth of nanocrystals or for catalysis in confined spaces. Secondly, the mesoporous silica shell enables the free diffusion of guest molecules through the intact shell. Thirdly, the outer silica surface is ready for chemical modifications, typically via its abundant Si-OH bonds. As early as 2003, researchers developed a soft-templating methodto prepare hollow aluminosilicate spheres with penetrating mesopores in a cubic symmetry pattern on the shells. However, adapting this method for applications on the nanoscale, especially for biomedicine, has proved difficult because the soft templating micelles are very sensitive to liquid environments, making it difficult to tune key parameters such as dispersity, morphology and structure. In this Account, we present the most recent developments in the tailored construction of highly dispersive and monosized HMSNs using simple silica-etching chemistry, and we discuss these particles' excellent performance in diverse applications. We first introduce general principles of silica-etching chemistry for controlling the chemical composition and the structural parameters (particle size, pore size, etching modalities, yolk-shell nanostructures, etc.) of HMSNs. Secondly, we include recent progress in constructing heterogeneous, multifunctional, hollow mesoporous silica nanorattles via several methods for diverse applications. These elaborately designed HMSNs could be topologically transformed to prepare hollow mesoporous carbon nanoparticles or functionalized to produce HMSN-based composite nanomaterials. Especially in biomedicine, HMSNs are excellent as carriers to deliver either hydrophilic or hydrophobic anti-cancer drugs, to tumor cells, offering enhanced chemotherapeutic efficacy and diminished toxic side effects. Most recently, research has shown that loading one or more anticancer drugs into HMSNs can inhibit metastasis or reverse multidrug resistance of cancer cells. HMSNs could also deliver hydrophobic perfluorohexane (PFH) molecules to improve high intensity focused ultrasound (HIFU) cancer surgery by changing the tissue acoustic environment; and HMSNs could act as nanoreactors for enhanced catalytic activity and/or durability. The versatility of silica-etching chemistry, a simple but scalable synthetic methodology, offers great potential for the creation of new types of HMSN-based nanostructures in a range of applications.

High surface area mesoporous LaCoO3 oxides (270 m2 g−1) with well crystallized perovskite framework have been successfully prepared via a simple one-step co-nanocasting method using the mesoporous SiO2 (KIT-6) template. The prepared mesoporous LaCoO3 material shows relatively high catalytic activity for CO oxidation and the complete CO conversion has been achieved at about 190 °C, which is about 75 °C lower than that of the non-mesoporous LaCoO3. Moreover, compared with non-mesoporous counterpart, the prepared mesoporous LaCoO3 possesses much higher catalytic activity for NO oxidation, showing rather higher NOx storage capacity. The NO removal ratio is high up to 64% under low temperature (310 °C). The enhanced catalytic activity of the mesoporous LaCoO3 for CO and NO oxidation is attributed to its high surface area and crystal lattice defects. A catalytic mechanism of CO and NO oxidation was proposed.

A novel template-free approach, the controlled thermal decomposition of single-phase Fe–Mn binary oxalate, was proposed and used to synthesize mesoporous Fe–Mn binary oxide, which possessed homogeneous worm-like mesopores (4–5 nm) and high surface areas above 200 m 2 /g. The catalyst was efficient in the catalytic removal of low-concentration NO at room temperature: 100% removal of 10 ppm NO in the first 4 h at a high space velocity of 40,000 h −1 on a Fe–Mn binary oxide with a Fe/Mn ratio of 1/4 calcined at 300 °C. Catalysts with other Fe/Mn ratios or calcined at higher temperatures showed lower NO removal performances. A synergetic effect between Mn n + and Fe n + was proposed and believed to be responsible for the catalytic conversion of NO and O 2 into NO 2 , which was subsequently adsorbed and/or absorbed as nitrates on the binary oxide.

A special "small to big" temperature-responsive phase-transformation strategy based on the "acoustic droplet vaporization (ADV)" mechanism is developed for efficient targeted ultrasonography and synergistic high intensity focused ultrasound (HIFU) cancer surgery by engineering targeted nanoemulsions, which is systematically evaluated and successfully demonstrated in vitro, ex vivo, and in vivo.

Dual-mesoporous ZSM-5 zeolite with highly b axis oriented large mesopores was synthesized by using nonionic copolymer F127 and cationic surfactant CTAB as co-templates. The product contains two types of mesopores--smaller wormlike ones of 3.3 nm in size and highly oriented larger ones of 30-50 nm in diameter along the b axis--and both of them interpenetrate throughout the zeolite crystals and interconnect with zeolite microporosity. The dual-mesoporous zeolite exhibits excellent catalytic performance in the condensation of benzaldehyde with ethanol and greater than 99 % selectivity for benzoin ethyl ether at room temperature, which can be ascribed to the zeolite lattice structure offering catalytically active sites and the hierarchical and oriented mesoporous structure providing fast access of reactants to these sites in the catalytic reaction. The excellent recyclability and high catalytic stability of the catalyst suggest prospective applications of such unique mesoporous zeolites in the chemical industry.

A novel Cu/Mn co-loaded mesoporous ZrO 2 –TiO 2 (ZT) composite has been successfully synthesized, in which Cu species were first introduced by co-hydrolysis of copper precursor with zirconium and titanium precursors, following on loading with Mn species via an in situ redox reaction between KMnO 4 and the surfactant template. The prepared samples were characterized by XRD, N 2 sorption, TEM, SEM, H 2 -TPR, UV–vis and XPS techniques, etc . CO catalytic oxidation was chosen as a model reaction to investigate the distinctively synergetic catalytic effect in the prepared co-loaded sample. Compared with single component of Cu or Mn loaded samples, the co-loaded CuMnZT demonstrated much enhanced catalytic activity at the Cu content of ⩾2.2 wt%. A possible synergetic catalytic effect among the Cu, Mn species and mesoporous ZrO 2 –TiO 2 matrix was proposed and discussed in detail.

A novel porous CuO x /CeO 2 co-loaded ZrO 2 –TiO 2 (ZT) nanocomposite with tunable pore structure and high surface area was prepared by a simple surfactant-free solvothermal method. The pore structure could be well controlled by adjusting the ratio of ethanol to H 2 O during the solvothermal process. Both copper oxides and ceria species could be homogeneously loaded into porous ZT nanocomposite by either incorporation into ZT framework or dispersion into the pore channels. Two kinds of novel catalysts with different pore structures have been synthesized and exhibit excellent soot catalytic combustion performance, owing to the porous structure and the active components of CuO x /CeO 2 .

Multifunctional organic/inorganic hybrid nanovesicles, fabricated by a facile self-assembly/sol-gel approach, display a unique morphology (figure) and satisfactory stability under physiological conditions. By co-encapsulation of superparamagnetic magnetite nanoparticles and a liquid perfluorocarbon, the nanovesicles can be used not only as a dual-modality ultrasound/magnetic resonance contrast agent for accurate cancer diagnosis and monitoring, but also as a therapeutic enhancement agent for effective high-intensity focused ultrasound (HIFU) ablation.

An extraordinarily high catalytic performance of up to 28% cyclohexane conversion and above 93% selectivity for cyclohexanone and cyclohexanol in the cyclohexane oxidation has been achieved under mild conditions by using copper-doped hierarchically micro/mesoporous zeolite ZSM-5, which has been fabricated by a facile one-pot hydrothermal synthetic process at a relatively low hydrolysis temperature. The excellent catalytic activity was ascribed to the highly dispersed framework copper ions (Cu+/Cu2+) as catalytic active sites and the hierarchically porous structure to provide the fast diffusion pathway for reactant/product molecules. The presence of the framework Cu(I) was proposed to promote the decomposition of H2O2 and the formation of radicals HO, and thus accelerate the selective oxidation of cyclohexane. More importantly, the synthesized catalyst showed excellent recyclable properties, demonstrating the high catalytic stability and future application prospect of such hierarchical heterogeneous catalysts in chemical industry. (C) 2012 Elsevier B.V. All rights reserved.

Inspired by considerable application potential in various diseases, nitric oxide (NO) has gained increasing attention. Nevertheless, current NO release scaffolds suffer from some inevitable drawbacks, for example, high toxicity for NO donor byproducts, poor specificity, shallow penetration depth, and strong ionizing irradiation for triggers, all of which remain obstacles to clinical application. Herein, an ultrasound-triggered NO on-demand release system is constructed using natural l-arginine as NO donor and local ultrasound as trigger. The focused ultrasound can activate H2O2 to generate more oxygen-contained species (ROS) of stronger oxidation ability than H2O2 for oxidizing LA via the energy transformation from ultrasound mechanical energy to chemical energy, and thus produce more NO for ultimately suppressing the highly aggressive and lethal Panc-1 tumor. Moreover, a blood vessel–intercellular matrix–cell “relay” targeting strategy has been established and relying on it, over 7-fold higher retention ...

Ultrasound is critical in many areas of medicine including obstetrics, oncology, and cardiology with emerging applications in regenerative medicine. However, one critical limitation of ultrasound is the low contrast of target tissue over background. Here, we describe a novel cup-shaped silica nanoparticle that is reminiscent of exosomes and that has significant ultrasound impedance mismatch for labelling stem cells for regenerative medicine imaging. These exosome-like silica nanoparticles (ELS) were created through emulsion templating and the silica precursors bis(triethoxysilyl)ethane (BTSE) and bis(3-trimethoxysilyl-propyl)amine (TSPA). We found that 40% TSPA resulted in the exosome like-morphology and a positive charge suitable for labelling mesenchymal stem cells. We then compared this novel structure to other silica structures used in ultrasound including Stober silica nanoparticles (SSN), MCM-41 mesoporous silica nanoparticles (MSN), and mesocellular foam silica nanoparticles (MCF) and found that the ELS offered enhanced stem cell signal due to its positive charge to facilitate cell uptake as well as inherently increased echogenicity. The in vivo detection limits were