Organosilica Shell Research Articles

Dynamic Solid-State Ultrasound Contrast Agent for Monitoring pH Fluctuations In Vivo.

The key challenge for in vivo biosensing is to design biomarker-responsive contrast agents that can be readily detected and monitored by broadly available biomedical imaging modalities. While a range of biosensors have been designed for optical, photoacoustic, and magnetic resonance imaging (MRI) modalities, technical challenges have hindered the development of ultrasound biosensors, even though ultrasound is widely available, portable, safe, and capable of both surface and deep tissue imaging. Typically, contrast-enhanced ultrasound imaging is generated by gas-filled microbubbles. However, they suffer from short imaging times because of the diffusion of the gas into the surrounding media. This demands an alternate approach to generate nanosensors that reveal pH-specific changes in ultrasound contrast in biological environments. Silica cores were coated with pH-responsive poly(methacrylic acid) (PMASH) in a layer-by-layer (LbL) approach and subsequently covered in a porous organosilica shell. Transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM) were employed to monitor the successful fabrication of multilayered particles and prove the pH-dependent shrinkage/swelling of the PMASH layer. This demonstrates that reduction in pH below healthy physiological levels resulted in significant increases in ultrasound contrast, in gel phantoms, mouse cadaver tissue, and live mice. The future of such materials could be developed into a platform of biomarker-responsive ultrasound contrast agents for clinical applications.

Nanoporous hybrid core-shell nanoparticles for sequential release.

In this article, a new type of core-shell nanoparticle is introduced. In contrast to most reported core-shell systems, the particles presented here consist of a porous core as well as a porous shell using only non-metal materials. The core-shell nanoparticles were successfully synthesized using nanoporous silica nanoparticles (NPSNPs) as the starting material, which were coated with nanoporous phenylene-bridged organosilica, resulting in a total particle diameter of about 80 nm. The combination of a hydrophilic nanoporous silica core and a more hydrophobic nanoporous organosilica shell provides regions of different chemical character and slightly different pore sizes within one particle. These different properties combined in one particle enable the selective adsorption of guest molecules at different parts of the particle depending on the molecular charge and polarity. On the other hand, the core-shell make-up of the particles provides a sequential release of guest molecules adsorbed at different parts of the nanoparticles. As a proof of concept, loading and release experiments with dyes were performed using non polar fluorescein and polar and charged methylene blue as model guest molecules. Non polar fluorescein is mostly adsorbed on the hydrophobic organosilica shell and therefore quickly released whereas the polar methylene blue, accumulated in the hydrophilic silica core, is only released subsequently. This occurs in small doses for an extended time corresponding to a sustained release over at least one year, controlled by the organosilica shell which acts as a diffusion barrier. An initial experiment with two drugs - non polar ibuprofen and polar and charged procaine hydrochloride - has been carried out as well and shows that the core-shell nanoparticles presented here can also be used for the sequential release of more relevant combinations of molecules.

Stable Perovskite Quantum Dots Coated with Superhydrophobic Organosilica Shells for White Light-Emitting Diodes.

Metalammonium lead perovskite (MAPbX3 , MA=CH3 NH3 + ; X=Cl, Br, I) quantum dots (QDs) have attracted tremendous attention due to their outstanding optical properties. However, they usually suffer from poor stability towards water or moisture, which seriously limits their practical applications. Here, we report a simple and effective approach to improve the stability of MAPbBr3 QDs by encapsulating them with superhydrophobic fluorinated organosilica (FSiO2 ) shells. The water-resistant stability of the superhydrophobic MAPbBr3 QDs/FSiO2 is significantly enhanced and they display strong fluorescence even after immersion in water for 12 hours. This method is readily extended to prepare superhydrophobic MAPbBr2.4 Cl0.6 QDs/FSiO2 and MAPbI3 QDs/FSiO2 powders. These superhydrophobic MAPbX3 QDs/FSiO2 can be further used to fabricate white light-emitting diodes (LEDs) with comparable color to pure white emission.

Precision Cancer Theranostic Platform by In Situ Polymerization in Perylene Diimide-Hybridized Hollow Mesoporous Organosilica Nanoparticles.

Phototheranostics refers to advanced photonics-mediated theranostic methods for cancer and includes imaging-guided photothermal/chemotherapy, photothermal/photodynamic therapy, and photodynamic/chemotherapy, which are expected to provide a paradigm of modern precision medicine. In this regard, various phototheranostic drug delivery systems with excellent photonic performance, controlled drug delivery/release, and precise photoimaging guidance have been developed. In this study, we reported a special "in situ framework growth" method to synthesize novel phototheranostic hollow mesoporous nanoparticles by ingenious hybridization of perylene diimide (PDI) within the framework of small-sized hollow mesoporous organosilica (HMO). The marriage of PDI and HMO endowed the phototheranostic silica nanoparticles (HMPDINs) with largely amplified fluorescence and photoacoustic signals, which can be used for enhanced fluorescence and photoacoustic imaging. The organosilica shell can be chemically chelated with isotope 64Cu for positron emission tomography imaging. Moreover, in situ polymer growth was introduced in the hollow structure of the HMPDINs to produce thermosensitive polymer (TP) in the cavity of HMPDINs to increase the loading capacity and prevent unexpected leakage of the hydrophobic drug SN38. Furthermore, the framework-hybridized PDI generated heat under near-infrared laser irradiation to trigger the deformation of TP for controlled drug release in the tumor region. The fabricated hybrid nanomedicine with organic-inorganic characteristic not only increases the cancer theranostic efficacy but also offers an attractive solution for designing powerful theranostic platforms.

Nanoscale Metal-Organic-Frameworks Coated by Biodegradable Organosilica for pH and Redox Dual Responsive Drug Release and High-Performance Anticancer Therapy.

Responsive nanocarriers with biocompatibility and precise drug releasing capability have emerged as a prospective candidate for anticancer treatment. However, the challenges imposed by the complicated preparation process and limited loading capacities have seriously impeded the development of novel multifunctional drug delivery systems. Here, we developed a novel and dual-responsive nanocarrier based on a nanoscale ZIF-8 core and an organosilica shell containing disulfide bridges in its frameworks through a facile and efficient strategy. The prepared ZIF-8@DOX@organosilica nanoparticles (ZDOS NPs) exhibited a well-defined structure and excellent doxorubicin (DOX) loading capability (41.2%) with pH and redox dual-sensitive release properties. The degradation of the organosilica shell was observed after 12 h incubation with a 10 mM reducing agent. Confocal imaging and flow cytometry analysis further proved that the nanocarriers can efficiently enter cells and complete intracellular DOX release under the low pH and high glutathione concentrations, which resulted in an enhanced cytotoxicity of DOX for cancer cells. Meanwhile, subcellular localization experiments revealed that the ZDOS NPs entered cells mainly by endocytosis and then escaped from lysosomes into the cytosol. Moreover, in vivo assays also demonstrated that the ZDOS NPs exhibited negligible systemic toxicity and significantly enhanced anticancer efficiencies compared with free DOX. In summary, our prepared pH and redox dual-responsive nanocarriers provide a potential platform for controlled release and cancer treatment.

Synthesis and Characterization of Cu Decorated Zeolite A@Void@Et-PMO Nanocomposites for Removal of Methylene Blue by a Heterogeneous Fenton Reaction

In this paper, hydrothermal synthesized nano zeolite A has been encapsulated with ethyl bridged periodic mesoporous organosilica(Et-PMO) shell through a simple modified Stober method and an organosilane-directed growth-induced etching strategy, the obtained yolk-shell structured A@Et-PMO nanocomposite(YS-A@Et-PMO) was further functionalized by the impregnation of copper ions, realizing the composite material with hierarchical porous and catalytic properties. The morphology and metal content of the Cu/A and Cu/YS-A@Et-PMO were fully characterized. As compared to the parent material, the composite Cu/YS-A@Et-PMO has an efficient adsorption and catalytic degradation performance on methylene blue(MB), the removal efficiency reached as high as 95% of 60 mg/L MB within 10 min. These novel structured porous composites may have great potential application for the removal of organic dye including waste effluents.

Docosane-Organosilica Microcapsules for Structural Composites with Thermal Energy Storage/Release Capability.

Organic phase change materials (PCMs) represent an effective solution to manage intermittent energy sources as the solar thermal energy. This work aims at encapsulating docosane in organosilica shells and at dispersing the produced capsules in epoxy/carbon laminates to manufacture multifunctional structural composites for thermal energy storage (TES). Microcapsules of different sizes were prepared by hydrolysis-condensation of methyltriethoxysilane (MTES) in an oil-in-water emulsion. X-ray diffraction (XRD) highlighted the difference in the crystalline structure of pristine and microencapsulated docosane, and 13C solid-state nuclear magnetic resonance (NMR) evidenced the influence of microcapsules size on the shifts of the representative docosane signals, as a consequence of confinement effects, i.e., reduced chain mobility and interaction with the inner shell walls. A phase change enthalpy up to 143 J/g was determined via differential scanning calorimetry (DSC) on microcapsules, and tests at low scanning speed emphasized the differences in the crystallization behavior and allowed the calculation of the phase change activation energy of docosane, which increased upon encapsulation. Then, the possibility of embedding the microcapsules in an epoxy resin and in an epoxy/carbon laminate to produce a structural TES composite was investigated. The presence of microcapsules agglomerates and the poor capsule-epoxy adhesion, both evidenced by scanning electron microscopy (SEM), led to a decrease in the mechanical properties, as confirmed by three-point bending tests. Dynamic mechanical analysis (DMA) highlighted that the storage modulus decreased by 15% after docosane melting and that the glass transition temperature of the epoxy resin was not influenced by the PCM. The heat storage/release properties of the obtained laminates were proved through DSC and thermal camera imaging tests.

Facile Synthesis of Monodisperse Hollow Mesoporous Organosilica/Silica Nanospheres by an in Situ Dissolution and Reassembly Approach.

Hollow structured mesoporous organosilicas are a research hotspot because of their molecularly organic-inorganic hybrid frameworks, large void spaces, permeable shells, high surface areas, uniform pores, and various applications. However, the previous reported hard-core templating method and liquid-interface assembly approach suffered from complex preparation procedures and poor uniformity for the products. In this work, we demonstrate an in situ dissolution and reassembly method to synthesize monodisperse benzene-bridged hollow mesoporous organosilica/silica nanoparticles (HMOSNs) by sequential addition of tetraethoxysilane (TEOS) and 1,4-bis(triethoxysilyl)benzene in a solution containing a cetyltrimethylammonium bromide (CTAB) surfactant. The formation of HMOSNs is completed in one pot, which is very effective and convenient. The formation mechanism of HMOSNs is ascribed to the fact that TEOS first assembles with CTAB to form mesostructured silica cores, which further dissolve and migrate to the outer layers during the deposition of mesostructured organosilica shells. The prepared benzene-bridged HMOSNs possess uniform diameter (140 nm), large pore volume (2.79 m3/g), high specific surface area (2926 m2/g), and a high doxorubicin-loading content of 16.7%. HMOSNs can deliver doxorubicin (Dox) into human breast cancer cells and reduce their excretion. Thus, the Dox-loaded HMOSNs show a high killing effect against the cancer cells.

Dual Intratumoral Redox/Enzyme-Responsive NO-Releasing Nanomedicine for the Specific, High-Efficacy, and Low-Toxic Cancer Therapy.

Chemotherapy suffers numbers of limitations including poor drug solubility, nonspecific biodistribution, and inevitable adverse effects on normal tissues. Tumor-targeted delivery and intratumoral stimuli-responsive release of drugs by nanomedicines are considered to be highly promising in solving these problems. Compared with traditional chemotherapeutic drugs, high concentration of nitric oxide (NO) exhibits unique anticancer effects. The development of tumor-targeting and intratumoral microenvironment-responsive NO-releasing nanomedicines is highly desired. Here a novel kind of organic-inorganic composite nanomedicine (QM-NPQ@PDHNs) is presented by encapsulating a glutathione S-transferases π (GSTπ)-responsive drug O2 -(2,4-dinitro-5-{[2-(β-d-galactopyranosyl olean-12-en-28-oate-3-yl)-oxy-2-oxoethyl] piperazine-1-yl} phenyl) 1-(methylethanolamino)diazen-1-ium-1,2-dilate (NPQ) as NO donor and an aggregation-induced-emission (AIE) red fluorogen QM-2 into the cores of the hybrid nanomicelles (PEGylated disulfide-doped hybrid nanocarriers (PDHNs)) with glutathione (GSH)-responsive shells. The QM-NPQ@PDHN nanomedicine is able to respond to the intratumoral over-expressed GSH and GSTπ, resulting in the responsive biodegradation of the protective organosilica shell and NPQ release, and subsequent NO release within the tumor, respectively, and thus normal organs remain unaffected. This work demonstrates a paradigm of dual intratumoral redox/enzyme-responsive NO-release nanomedicine for tumor-specific and high-efficacy cancer therapy.

Highly Efficient Aqueous Synthesis of Propargylamines through C–H Activation Catalyzed by Magnetic Organosilica‐Supported Gold Nanoparticles as an Artificial Metalloenzyme

Highly efficient magnetic organosilica‐supported gold nanoparticles were developed as an artificial metalloenzyme for the synthesis of propargylamines through C–H activation in water under an ambient atmosphere. Herein, we present a very simple and efficient method for the deposition of Au nanoparticles on porous magnetic organosilica (Fe3O4@SiO2‐Cl) through the thermal reduction of an organometallic AuIII complex. As a nucleophile, a AuIII polypyridyl coordination complex could react with alkyl halides from the Fe3O4@SiO2‐Cl to form a quaternary ammonium salt as an ionic liquid; subsequently, the ligand was oxidized and the Au nanoparticles were embedded into the porous organosilica shell. The synergic effect of the gold nanoparticles as catalytically active sites, pyridinium chloride as a phase‐transfer agent, and the magnetite nanoparticle core, which could function as a protein mimic, endow the material with high efficiency, stability, recoverability, reusability, and good turnover frequency, all of which are necessary characteristic for an artificial enzyme. A reliable catalytic procedure for the synthesis of propargylamines was identified.

Surface Immobilization and Shielding of a Transaminase Enzyme for the Stereoselective Synthesis of Pharmaceutically Relevant Building Blocks.

Transaminases are enzymes capable of stereoselective reductive amination; they are of great interest in the production of chiral building blocks. However, the use of this class of enzymes in industrial processes is often hindered by their limited stability under operational conditions. Herein, we demonstrate that a transaminase enzyme from Aspergillus terreus can be immobilized at the surface of silica nanoparticles and protected in an organosilica shell of controlled thickness. The so-protected enzyme displays a high biocatalytic activity, and additionally provides the possibility to be retained in a reactor system for continuous operation and to be recycled.

Oxygen-Evolving Mesoporous Organosilica Coated Prussian Blue Nanoplatform for Highly Efficient Photodynamic Therapy of Tumors.

Oxygen (O2) plays a critical role during photodynamic therapy (PDT), however, hypoxia is quite common in most solid tumors, which limits the PDT efficacy and promotes the tumor aggression. Here, a safe and multifunctional oxygen‐evolving nanoplatform is costructured to overcome this problem. It is composed of a prussian blue (PB) core and chlorin e6 (Ce6) anchored periodic mesoporous organosilica (PMO) shell (denoted as PB@PMO‐Ce6). In the highly integrated nanoplatform, the PB with catalase‐like activity can catalyze hydrogen peroxide to generate O2, and the Ce6 transform the O2 to generate more reactive oxygen species (ROS) upon laser irradiation for PDT. This PB@PMO‐Ce6 nanoplatform presents well‐defined core–shell structure, uniform diameter (105 ± 12 nm), and high biocompatibility. This study confirms that the PB@PMO‐Ce6 nanoplatform can generate more ROS to enhance PDT than free Ce6 in cellular level (p < 0.001). In vivo, the singlet oxygen sensor green staining, tumor volume of tumor‐bearing mice, and histopathological analysis demonstrate that this oxygen‐evolving nanoplatform can elevate singlet oxygen to effectively inhibit tumor growth without obvious damage to major organs. The preliminary results from this study indicate the potential of biocompatible PB@PMO‐Ce6 nanoplatform to elevate O2 and ROS for improving PDT efficacy.

Dual Drug Delivery System Based on Biodegradable Organosilica Core-Shell Architectures.

To overcome drug resistance, efficient cancer therapeutic strategies using a combination of small-molecule drugs and macromolecule drugs is highly desired. However, because of their significant differences in molecular weight and size, it is difficult to load them simultaneously in one vector and to release them individually. Here, a biodegradable organosilica-based core-shell-structured nanocapsule was designed and used as a dual stimuli-responsive drug vector to solve this problem. Biodegradable organosilica shell coated outside the macromolecule model drug "core" would be disrupted by high glutathione (GSH) levels inside tumor cells, resulting in the escape of the entrapped drugs. Small-molecule drugs capping on the surface of the organosilica shell via pH-responsive imine bonds can be cut and released in the acidic lysosomal environment. Transmission electron microscopy has shown that the framework of the organosilica shell was dissolved and degraded after 8 h incubation with 5 mM GSH. Confocal imaging confirmed that small-molecule and macromolecular drugs were individually released from the nanoparticles because of the pH or redox-triggered degradation under the tumor microenvironment and thus led to the strong fluorescence recovery in the cytoplasm. As expected, these biodegradable organosilica nanoparticles could not release drugs into normal cells but could specifically release them into tumor cells owing to their tumor-triggered targeting capability. This system will serve as an efficient shuttle for multidrug delivery and also provide a potential strategy to overcome drug resistance.

Fluorescent Immunoassay for the Detection of Pathogenic Bacteria at the Single-Cell Level Using Carbon Dots-Encapsulated Breakable Organosilica Nanocapsule as Labels

Herein, carbon dots (CDs)-encapsulated breakable organosilica nanocapsules (BONs) were facilely prepared and used as advanced fluorescent labels for ultrasensitive detection of Staphylococcus aureus. The CDs were entrapped in organosilica shells by cohydrolyzation of tetraethyl orthosilicate and bis[3-(triethoxysilyl)propyl]disulfide to form core-shell CDs@BONs, where hundreds of CDs were encapsulated in each nanocapsule. Immunofluorescent nanocapsules, i.e., anti-S. aureus antibody-conjugated CDs@BONs, were prepared to specifically recognize S. aureus. Before fluorescent detection, CDs were released from the BONs by simple NaBH4 reduction. The fluorescent signals were amplified by 2 orders of magnitude because of hundreds of CDs encapsulated in each nanocapsule, compared with a conventional immunoassay using CDs as fluorescent labels. A linear range was obtained at the S. aureus concentration from 1 to 200 CFU mL-1. CDs@BONs are also expected to expand to other systems and allow the detection of ultralow concentrations of targets.

Nanosized Hollow Colloidal Organosilica Nanospheres with High Elasticity for Contrast-Enhanced Ultrasonography of Tumors.

Despite several reports on using silica hollow spheres as ultrasound contrast agents, they all suffer from their inherent drawbacks, e.g., poor imaging ability caused by highly rigid shell or large particles size that leads to failures of these particles in entering tumor tissues, no mesoporous channels to load other active molecules (e.g., fluorocarbons). In this report, amino groups-functionalized hollow colloidal organosilica nanospheres (HCONs) with approximately 260 nm in diameter are prepared. Depending on the thin and pure organosilica shell, the HCONs feature high elasticity beneficial for acquiring excellent ultrasonic imaging outcomes. Our in vitro experiment shows that the ultrasonic contrast increases 11 times and in vivo experiment also shows that the ultrasound imaging performance of tumor is improved for 1.5 times. More importantly, HCONs can load liquid perfluorohexane (PFH) capable of vaporizing into gas bubbles, which further enhance the ultrasonic imaging outcome. In addition, the organosilica nanospheres have a good biosafety, which is expected to become a new generation of ultrasound contrast agent.

Design and synthesis of organo-silica shell based dual-functional microencapsulated phase change material for thermal regulating systems

A novel form of dual-functional microcapsules with the core composition of phase change material with thermal energy storage capacity was formulated, which possessed photoluminescence features because of including rare earth nanoparticles in the core. Additionally, the core of the microcapsule is encapsulated by an organo-silica shell. The microcapsules were synthesized via interfacial polycondensation in a reverse emulsion templating system. The scanning electron microscope (SEM) and transmission electron microscopy (TEM) images of the formulated microcapsules presented a distinctive core–shell structure. The chemical compositions and crystalline structures of the microcapsules were confirmed by Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy, respectively. The fluorescence properties of the microcapsules were observed on an upright fluorescence microscope while the thermal properties of the microcapsules were evaluated by thermogravimetric analysis and differential scanning calorimetry. The results demonstrated that the developed strategy can certainly guide the design of multifunctional materials with numerous applications in the field of thermal energy storage.

Fabrication of propylsulfonic acid functionalized SiO2 core/PMO shell structured PrSO3H-SiO2@Si(R)Si nanospheres for the effective conversion of d-fructose into ethyl levulinate

Propylsulfonic acid functionalized SiO2 core/alkyl- or phenyl-bridged organosilica shell structured PrSO3H-SiO2@Si(R)Si (R=C2H4, C6H4 or C6H4C6H4) nanospheres are facilely prepared by a CTAB-directed one-pot two-step condensation strategy. The morphological characteristics, textural properties, Brønsted acid nature and structure of the PrSO3H-SiO2@Si(R)Si nanospheres are well characterized. The materials are successfully applied in the catalytic transformation of D-fructose into the important organic chemical, ethyl levulinate, in the presence of ethanol as both reactant and solvent. The catalytic activity of the PrSO3H-SiO2@Si(R)Si nanospheres outperform commercially available Amberlyst-15, HY zeolite and HCl, mainly attributing to their strong Brønsted acid nature; additionally, unique core-shell structure with excellent porosity properties and well-adjusted hydrophilicity/hydrophobicity also give the positive influence on the ethanolysis activity, which can improve the accessibility of the reactants to the PrSO3H sites and facilitate the multi-step ethanolysis reaction proceeding to the formation of the final product. The PrSO3H-SiO2@Si(R)Si nanospheres can be reused three times without obvious activity loss, contributed from covalent bonding of the PrSO3H groups with the silica and organosilica framework as well as hydrophobic PrSO3H-functionalized organosilica shell.

A multifunctional organosilica cross-linker for the bio-conjugation of gold nanorods

We report on the use of organosilica shells to couple gold nanorods to functional peptides and modulate their physiochemical and biological profiles. In particular, we focus on the case of cell penetrating peptides, which are used to load tumor-tropic macrophages and implement an innovative drug delivery system for photothermal and photoacoustic applications. The presence of organosilica exerts subtle effects on multiple parameters of the particles, including their size, shape, electrokinetic potential, photostability, kinetics of endocytic uptake and cytotoxicity, which are investigated by the interplay of colorimetric methods and digital holographic microscopy. As a rule of thumb, as the thickness of organosilica increases from none to ∼30nm, we find an improvement of the photophysical performances at the expense of a deterioration of the biological parameters. Therefore, detailed engineering of the particles for a certain application will require a careful trade-off between photophysical and biological specifications.

Core-shell hierarchical mesostructured silica nanoparticles for gene/chemo-synergetic stepwise therapy of multidrug-resistant cancer

The design and synthesis of hierarchically nanoporous structures for the co-encapsulation and sequential releases of different cargos are still great challenges in biomedical applications. In this work, we report on the elaborate design and controlled synthesis of a unique core-shell hierarchical mesoporous silica/organosilica nanosystem, in which there are large and small mesopores separately present in the shell and core, facilitating the independent encapsulations of large (siRNA) and small (doxorubicin) molecules, respectively. Importantly, the framework of the organosilica shell is molecularly hybridized with disulfide bonds, which enables the unique responsiveness to the reductive tumor microenvironment for the controlled releasing of loaded gene molecules, followed by the subsequent doxorubicin release. The first released large siRNA molecules from the organosilica shell down-regulated the expression of P-gp in the cell membrane and reversed the MDR of cancer cells, thus enhancing the antitumor effect of subsequently released small DOX molecules from the silica core, and in such a synergetic way the MDR tumor growth can be efficiently inhibited. This work shows the significant advantages compared to the traditional small-mesoporous or large-mesoporous nanosystems for drug co-delivery.

Rattle-Structured Upconversion Nanoparticles for Near-IR-Induced Suppression of Alzheimer's β-Amyloid Aggregation.

Rose bengal (RB)-loaded upconverting nanocomposites are synthesized as a near-infrared (NIR)-responsive inhibitor of Aβ aggregation. Rattle-structured, organosilica shell (ROS) is deposited on NaYF4 :Yb,Er nanocrystals (UCNPs) for high loading efficiency and disaggregation of RB. RB/UCNP@ROS successfully inhibits Aβ self-assembly under NIR irradiation by generating 1 O2 . Furthermore, photoexcited RB/UCNP@ROS is effective in suppressing Aβ-induced cytotoxicity.