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Since Cu2+ ions play a pivotal role in both ecosystems and human health, the development of a rapid and sensitive method for Cu2+ detection holds significant importance. Fluorescent mesoporous silica materials (FMSMs) have garnered considerable attention in the realm of chemical sensing, biosensing, and bioimaging due to their distinctive structure and easily functionalized surfaces. As a result, numerous Cu2+ sensors based on FMSMs have been devised and extensively applied in environmental and biological Cu2+ detection over the past few decades. This review centers on the recent advancements in the methodologies for preparing FMSMs, the mechanisms underlying sensing, and the applications of FMSMs‐based sensors for Cu2+ detection. Lastly, we present and elucidate pertinent perspectives concerning FMSMs‐based Cu2+ sensors. [ABSTRACT FROM AUTHOR]

Micro/nanoscale robotics has received great attention in many important fields. However, it is still a great challenge to construct nanorobots simultaneously possessing multifunctionality, well‐controlled directionality, and fast and durable motion as well as fully compatible and biodegradable components. Here, a hierarchical, asymmetric, hollow, catalytic, magnetic, and mesoporous nanorobot has been fabricated through a multistep interfacial superassembly strategy. The multilayer composites consist of hollow silica nanoflasks sequentially coated with a highly magnetic responsive Fe3O4 layer, a mesoporous silica layer with homogeneous vertical channels, and a layer of catalytic gold nanoparticles on both the inner and outer surfaces. Furthermore, para‐nitrophenol was used as a model pollutant to trigger self‐motility of the nanoflasks by confined catalytic degradation (CCD). We found that the bottleneck morphology and mesoporous surface both improved the catalytic nanoparticle loading capability and CCD effect, thus enabling efficient self‐motility and a durable movement capacity of ∼100 h. In addition, the catalytic performance was improved by 180 % compared with that of solid spherical nanoparticles. [ABSTRACT FROM AUTHOR]

Mesoporous silica nanoparticles (MSNs) functionalized with benzimidazole‐derived fluorescent molecules (DHBM) are fabricated via a feasible interfacial superassembly strategy for the highly sensitive and selective detection of Cu2+. DHBM‐MSN exhibits an obvious quenching effect on Cu2+ in aqueous solutions, and the detection limit can be as low as 7.69×10−8 M. The DHBM‐MSN solid‐state sensor has good recyclability, and the silica framework can simultaneously improve the photostability of DHBM. Two mesoporous silica nanoparticles with different morphologies were specially designed to verify that nanocarriers with different morphologies do not affect the specific detectionability. The detection mechanism of the fluorescent probe was systematically elucidated by combining experimental results and density function theory calculations. Moreover, the detection system was successfully applied to detect Cu2+ in bovine serum, juice, and live cells. These results indicate that the DHBM‐MSN fluorescent sensor holds great potential in practical and biomedical applications. [ABSTRACT FROM AUTHOR]

Nanofluidic devices have been widely used for diode‐like ion transport and salinity gradients energy conversion. Emerging reverse electrodialysis (RED) nanofluidic systems based on nanochannel membrane display great superiority in salinity gradient energy harvesting. However, the imbalance between permeability and selectivity limits their practical application. Here, a new mesoporous carbon‐silica/anodized aluminum (MCS/AAO) nanofluidic device with enhanced permselectivity for temperature‐ and pH‐regulated energy generation was obtained by interfacial super‐assembly method. A maximum power density of 5.04 W m−2 is achieved, and a higher performance can be obtained by regulating temperature and pH. Theoretical calculations are further implemented to reveal the mechanism for ion rectification, ion selectivity and energy conversion. Results show that the MCS/AAO hybrid membrane has great superiority in diode‐like ion transport, temperature‐ and pH‐regulated salinity gradient energy conversion. [ABSTRACT FROM AUTHOR]

The production of excess free zinc ions (Zn2+) in cells has been identified as an important cause of cell injury or apoptosis after ischemia reperfusion. Thus, developing a nanosystem with multiple therapeutic functions to significantly eliminate multiple cell injury factors is of great interest. Here, a super-assembled nanosystem consisting of a polyethylene glycol (PEG) surface-modified mesoporous silica nanoparticle (MSN) encapsulating 2-methylimidazole (2MI) and a Zn2+ probe (PZn) was fabricated. The 2MI-P@MSN nanoassemblies showed a "turn-on" fluorescence signal at 476 nm toward zinc ions due to the presence of PZn. Besides, zeolitic imidazolate framework-8 (ZIF-8) could be assembled on the site intracellularly after 2MI chelating with free zinc ions. The experimental results revealed that 2MI-P@MSN exhibited excellent biocompatibility and non-cytotoxicity, and was able to provide satisfactory protection to OGD/R-treated cells based on zinc ion adsorption and the antioxidant effect of ZIF-8, which could effectively improve the survival rate of reperfusion injury cells from 52% to 73%. Notably, selective and quantitative sensing of Zn2+ was successfully carried out in the cells. This strategy highlights the potential of the detection, absorption and assembly of excess zinc ions simultaneously for cell therapy, which provides a promising therapeutic method for ischemic stroke, oxidative damage and diseases associated with zinc ion accumulation. [ABSTRACT FROM AUTHOR]

Asymmetric hollow and magnetic mesoporous silica nanocomposites have great potential applications due to their unique structural–functional properties. Here, asymmetric multilayer‐sandwich magnetic mesoporous silica nanobottles (MMSNBs) are presented through an interfacial super‐assembly strategy. Asymmetric hollow silica nanobottles (SNBs) are first prepared, and Fe3O4 nanoparticles monolayers and mesoporous silica layers are uniformly super‐assembled on the surfaces of SNBs, respectively. The high Fe3O4 nanoparticles loading endows MMSNBs with a high magnetization (8.5 emu g−1), while the mesoporous silica layers exhibit high surface area (613.4 m2 g−1) and large pore size (3.6 nm). MMSNBs can be employed as a novel type of enzyme‐powered nanomotors by integrating catalase (Cat‐MMSNBs), which show an average speed of 7.59 µm s−1 (≈25 body lengths s−1) at 1.5 wt% H2O2. Accordingly, the water quality can be monitored by evaluating the movement speed of Cat‐MMSNBs. Moreover, MMSNBs act as a good adsorbent for removing more than 90% of the heavy metal ions with the advantage of the mesoporous structure. In addition, the good magnetic response enables the MMSNBs with precise directional control and is conducive to recycling for repeated operation. This bottom‐up interfacial super‐assembly construction strategy allows for a new understanding of the rational design and synthesis of multi‐functional nanomotors. [ABSTRACT FROM AUTHOR]

Functionalized mesoporous silica materials (MSMs) are extensively investigated in sensing science due to their diverse structural and optical properties including tunable pore size, modifiable surface properties, and excellent accessibility to active sites. In the last few years, great efforts have been devoted to developing modification methods for MSMs for sensing applications with augmented sensitivity, super selectivity, as well as targeting capability, and multimodal capabilities. The functional group, structure, morphology, and component levels in the assembly of heterostructures of MSMs are a key for high sensing performance. As the development of mesoporous silica‐based sensing materials progresses, diverse functional units and materials are rationally implemented into the mesoporous structures. These heterostructures can maintain the excellent structural features of mesoporous silica and the optical properties of the functional units simultaneously, which shows the advantages of photostability, design flexibility, and multifunctionality. Here, an up‐to‐date overview of the fabrication strategies, the properties, and the sensing mechanisms of optical heterostructures based on MSMs is provided. A number of crucial sensing domains, including ionic, molecules, temperature, and biological species are highlighted. Finally, the prospects and potential sensing applications of mesoporous silica‐based optical heterostructures are discussed. [ABSTRACT FROM AUTHOR]

Mesoporous Silica Materials: Interfacial Assembly of Mesoporous Silica-Based Optical Heterostructures for Sensing Applications (Adv. Funct. In article number 1906950, Dongyuan Zhao, Biao Kong, and co-workers provide a comprehensive overview of the fabrication strategies and properties and the sensing mechanism of optical heterostructures in mesoporous silica materials. In addition, the advantages of and pioneering studies on mesoporous silica materials in terms of sensing applications are described. [Extracted from the article]

Bioinspired artificial nanochannels have emerged as promising candidates for developing smart nanofluidic sensors due to their highly controllable size and surface functionality. However, little attention has been paid to the role of the outer surface of the nanochannels in enhancing the detection sensitivity. Herein, an asymmetric nanochannel-based responsive detection platform with ultrathin tannic acid modified mesoporous silica (TA-MS) layer and alumina oxide (AAO) thin film is prepared through super-assembly strategy. The functional TA-MS outer surface layer provides abundant phenolic groups on the nanochannels for ions and molecules transport, which paves the way for the development of heterochannels for label-free, reversible and highly sensitive dopamine (DA) detection based off of cation displacement effect. Notably, by engineering optimal thickness of the TA-MS, the sensing performance can be further improved. After optimization, the linear response ranges for DA detection are 0.001–1 μM, 1–10 μM and 10–200 μM with the detection limit of 0.1 nM. The prepared sensor exhibits stable reversibility after several detection cycles. In addition, this method was successfully applied for DA detection in fetal bovine serum sample. Theoretical calculations further prove the detection mechanism. This work opens a new horizon of using mesoporous materials to construct nanofluidic sensors for ultrasensitive small molecule detection and recognition. A functional nanofluidic channels-based sensor based on mesoporous thin film is developed for label-free, sensitive and reversible detection of dopamine (DA). Based on a metal ion displacement reaction, the asymmetric nanochannels can be activated from "closed" to "open" state for ion transport in response to DA, which provides the response of the ionic current against DA concentrations. [Display omitted] [ABSTRACT FROM AUTHOR]