Magnetic Mesoporous Silica Research Articles

Asymmetrically coating Pt nanoparticles on magnetic silica nanospheres for target cell capture and therapy.

AJanus cargo has been developedvia the combination of magnetic mesoporous silica (MMS) with asymmetric decoration of Pt nanoparticles (PtNPs). Mesoporous morphology of MMS provides plenty of space for loading photosensitizers and targeting agents; the magnetic feature endows the as-formed nanospheres with satisfactory isolation function in removal of low abundant target cells. The excellent catalytic ability of PtNPs can effectively alleviate the hypoxia condition of tumor microenvironment via the decomposition of hydrogen peroxide (H2O2), as well as an O2-drived nanomotor for highly efficient drug release. Using CCRF-CEM as the model target cell, the Janus cargo is demonstrated to possess significantly improved performance in cell capture and photodynamic therapy. Specially, owing to the patchy Pt decoration, the loaded photosensitizers exhibit a more efficient release behavior. More importantly, asymmetric O2-emission from one side of the nanocargo acts as a driving force, which could effectively accelerate the motion ability of cargo in cell media, thus leading to an enhanced therapeutic effect compared withthe traditionally symmetric nanocargo. This Janus cargo would offer a new paradigm to design highly efficient drug carrier for gaining an improved photodynamic therapy in hypoxic cancer cells.

Adsorption of uranium by diethylenetriamine functionalized magnetic mesoporous silica

The iron oxide (Fe3O4) embedded mesoporous silica was prepared and functionalized with diethylenetriamine (DETA) functional groups for the separation of uranium from aqueous medium. The prepared product was abbreviated as Fe-MCM-DETA. The Fe-MCM-DETA was characterized by Raman spectroscopy, particle size distribution, X-ray diffraction, BET surface area, BJH pore size distribution, thermogravimetry, FT-IR, scanning electron microscopy, and transmission electron microscopy. The adsorption of uranium on Fe-MCM-DETA was evaluated as a function of various aqueous phase parameters such as pH, duration of equilibration, concentration of uranium in the aqueous phase, and presence of interfering ions. The adsorption of uranium on Fe-MCM-DETA followed the second-order rate equation. The maximum adsorption capacity of uranium was determined to be ∼470 mg.g−1 at pH 6 by Langmuir adsorption isotherm modeling. The results obtained from adsorption studies and the physical properties of Fe-MCM-DETA were compared with DETA functionalized on Fe3O4 (Fe-DETA), silica gel (Si-DETA), and mesoporous silica (MCM-DETA). The uranium loaded on Fe-MCM-DETA was retrieved using Na2CO3 solution, the feasibility for recycling of Fe-MCM-DETA without much loss of adsorption capacity was studied, and the results are reported in this paper.

Synthesis of Magnetic Short-Channel Mesoporous Silica SBA-15 Modified with a Polypyrrole/Polyaniline Copolymer for the Removal of Mercury Ions from Aqueous Solution.

A novel magnetic short-channel mesoporous silica SBA-15 composite adsorbent was prepared by the copolymerization of pyrrole and aniline. The prepared novel nanoadsorbent polypyrrole–polyaniline/CoFe2O4-SBA-15 (PPy-PANI/M-SBA-15) has a significant adsorption effect on heavy metal mercury ions. The batch adsorption experiment was carried out to study the effects of various parameters including solution pH, initial concentration (C0), adsorbent dose (dosage), temperature (T), and contact time on the adsorption effect. The analysis results of the response surface method (RSM) and central composite design (CCD) show that the importance for adsorption factors is pH > C0 > T > dosage, and the maximum capacity of PPy-PANI/M-SBA-15 is 346.2 mg/g under the optimal conditions of pH = 6.7, T = 310 K, C0 = 29.5 mg/L, and a dosage of 0.044 g/L. The pseudo-second-order kinetic model and the Langmuir isotherm model simulate the adsorption behavior of mercury ions. In addition, thermodynamic parameters indicate self-heating and reversible adsorption processes. A covalent bond is formed between the nitrogen-containing functional group and the mercury ions. Excellent magnetic properties and high reproducibility indicate that PPy-PANI/M-SBA-15 has excellent recyclability and environmentally friendly properties and can become a potential heavy metal ion adsorbent in practical applications.

4-Nitrophenol-Loaded Magnetic Mesoporous Silica Hybrid Materials for Spectrometric Aptasensing of Carcinoembryonic Antigen.

Aptamer- or antibody-based sensing protocols have been reported for detecting carcinoembryonic antigen (CEA), but most exhibit complicated procedures or multiple reactions. In this work, we developed a one-step aptasensing protocol for the spectrometric determination of CEA based on 4-nitrophenol (4-NP)-loaded magnetic mesoporous silica nanohybrids (MMSNs) for bioresponsive controlled-release applications. To fabricate such a responsive–controlled sensing system, single-stranded complementary oligonucleotides relative to the CEA-specific aptamer were first modified on the aminated MMSN. Thereafter, 4-NP molecules blocked the pores with the assistance of the aptamers via a hybridization reaction. The introduced target CEA specifically reacted with the hybridized aptamer, thus detaching from the MMSN to open the gate. The loaded 4-NP molecules were released from the pores, as determined using ultraviolet–visible (UV–vis) absorption spectroscopy after magnetic separation. Under optimum conditions, the absorbance increased with an increase in the target CEA in the sample and exhibited a good linear relationship within the dynamic range of 0.1–100 ng mL−1, with a detection limit of 46 pg mL−1. Moreover, this system also displayed high specificity, good reproducibility, and acceptable accuracy for analyzing human serum specimens, in comparison with a commercialized human CEA-enzyme-linked immunosorbent assay (ELISA) kit.

Galactosylated Chitosan Modified Magnetic Mesoporous Silica Nanoparticles Loaded with Nedaplatin for the Targeted Chemo-Photothermal Synergistic Therapy of Cancer.

The use of chemotherapy combined with photothermal therapy (PTT) is getting a focus topic for cancer treatment. Duing this research, the double targeting drug delivery system of nedaplatin (NDP)-carboxyl-functionalized magnetic mesoporous silica (MMSN-COOH)-galactosylated chitosan (GC) nanoparticles (NPs) was constructed. Because MMSNs have special physical properties, it can target to the specific area. In addition, it's able to convert absorbed near-infrared (NIR) light into heat energy for photothermal therapy (PTT). Furthermore, the thermal energy generated by MMSNs under NIR lasers can accelerate the release of drug from preparations. Moreover, GC modified MMSNs-COOH as a carrier can increase the drug uptake of cancer cells that highly express galectins in vitro, resulting in cancer cell apoptosis, and thus increasing the targeting of cancerous tissue in vivo. The experimental consequences in vitro and in vivo revealed that the NDP@MMSNCOOH-GC NPs combined with PTT could avoid systemic toxicity and improve biosecurity while having good anticancer effect.

Magnetic Mesoporous Silica Nanoparticles Incorporated with miR-451 Suppress Development of Cervical Cancer and Enhance Radio Sensitization in Cervical Cancer

Cervical cancer (CC) is one of the most common gynecological malignancies with high mortality, threatening female’s health and reducing their life quality. This study evaluated the synergistic effect of magnetic mesoporous silica nanoparticles (MMSNs), miR-451 on radio sensitivity and cell apoptosis in CC. Magnetic mesoporous silica (Fe3O4/SiO2) nanoparticles were prepared and loaded with miR-451. Then the CC cells were treated with Fe3O4/SiO2 nanoparticles, miR-451-loaded Fe3O4/SiO2 nanoparticles (control group) and untreated (blank group). Cell proliferation was determined by MTT assay, while apoptosis and Hoechst were assessed by flow cytometry. As colony formation assay was conducted to evaluate cell sensitivity to radiotherapy, Western blot analysis detected the expression of apoptosis- and radiosensitization-related genes. Iron oxide particles were present inside and outside the SiO2 channel with characteristic peaks for Fe and skeleton of silica. The miR-451-loaded Fe3O4/SiO2 nanoparticles had an obvious absorption peak with drug loading rate and encapsulation rate reaching 6% and 91%. The release content of drugs increased with decreased pH. Of note, combined treatment with miR-451 and Fe3O4/SiO2 nanoparticles significantly decreased cancer cell proliferation and increased apoptosis (34.36±2.31%), compared to control group and blank group. Furthermore, the levels of D0 (1.67), Dq (0.94), N (1.56), and SF2 (0.43) declined in the presence of miR-451-Fe3O4/SiO2 nanoparticles, accompanied with elevation of ATM and γ-H2AX expression. Meanwhile, the treated CC cells had decreased expressions of DNA damage repair related genes ATM and γ-H2AX. MMSNs carrying miR-451 decreased cell proliferation activity and increased apoptosis and sensitized the CC cells to radiotherapy, to improve tissue repairing. These findings may provide a novel insight into pathogenesis of CC.

Hydrophobic Drug Release Studies from the Core/Shell Magnetic Mesoporous Silica Nanoparticles and their Anticancer Application

Multiple therapeutic hydrophobic drugs can be delivered simultaneously by inorganic, biocompatible iron core mesoporous silica shell nanoparticles. We synthesized superparamagnetic iron oxide nanocrystals encapsulated within mesostructured silica spheres through the sol-gel process. The dose of hydrophobic drugs Paclitaxel (PTX) and Camptothecin (CPT) loading and released on Fe3 O4 @SiO2 core/shell nanoparticle detected by U.V-visible spectrophotometry using a platform of nanoparticles (NPS). After being subjected to external heating, the drug release efficiency of paclitaxel (PTX) and camptothecin (CPT) Fe3 O4 @SiO2 core/shell nanoparticles is increased. Paclitaxel (PTX) and Camptothecin (CPT) Fe3 O4 @SiO2 core/shell nanoparticles did not heat the solution when an alternating magnetic field (AMF) was applied, and there was only mild drug leakage. When compared to Fe3 O4 @MSNs, the nanoparticles (PTX) and (CPT) Fe3 O4 @MSNs function as cancer-targeting mediators, increasing the killing of PANC-1 cancer cells. Human cancer cells were given these therapeutic anticancer water-insoluble drugs with nanoparticles, which is a valuable vehicle for drug delivery, and induced the inhibition of proliferation. Therefore, the goal of this study to emphasize Fe3 O4 @SiO2 core/shell potential as a superior candidate for hydrophobic drug delivery to the PANC-1 cancer cell.

One-step fabrication of strongly hydrophilic mesoporous silica for comprehensive analysis of serum glycopeptidome

Glycopeptidome represents reliable predictors of physiological and pathological status. Obstructions mainly including low abundance of endogenous glycopeptides and varied interference necessitate glycopeptide enrichment prior to MS analysis. Inspired by the prevalence of hydrophilic interaction chromatography for glycopeptide enrichment, a novel magnetic mesoporous silica nanomaterial (Fe3O4@mSiO2-TSG) with strongly hydrophilic property was developed through a one-pot method. In this work, the gluconamide-containing organosilane is innovatively proposed to directly serve as the strongly hydrophilic silica source for fabrication of hydrophilic mesoporous silica nanomaterial for glycopeptidomics research. Apart from excellent hydrophilicity, Fe3O4@mSiO2-TSG also was equipped with large specific surface area, ordered mesopore channels and great magnetic responsiveness. With all the advantages, Fe3O4@mSiO2-TSG displayed remarkable size-exclusion effect and considerable reusability. Moreover, combined with nano-LC-MS/MS, the glycopeptidome of serum from breast cancer patients was analyzed comprehensively, which showed noteworthy difference from healthy serum through gene ontology analysis, indicating great potential of the approach for glycopeptidomics research.

Determination of fipronil and its metabolites in egg samples by UHPLC coupled with Q-Exactive high resolution mass spectrometry after magnetic solid-phase extraction

A novel, rapid and simple magnetic solid-phase extraction (MSPE) method combined with ultra-high performance liquid chromatography coupled with Q-Exactive high resolution mass spectrometry (UHPLC-Q-Exactive HRMS) was proposed for determination of fipronil and its metabolites in egg samples. In this study, novel polydopamine functionalized magnetic core-shell mesoporous silica nanoparticles (Fe3O4@nSiO2@mSiO2-PDA) were used as MSPE adsorbent for purification and enrichment of fipronil and its metabolites for the first time. The proposed method showed a good linearity (R2 ≥ 0.997), high sensitivity (limit of detection in the range of 0.002–0.004 μg/kg and limit of quantification in the range of 0.006–0.010 μg/kg), adequate recovery (80.6–95.3%) and repeatability (intra-day precision in the range of 2.2–6.7% and inter-day precision in the range of 4.4–10.7%). Finally, the developed MSPE-UHPLC-Q-Exactive HRMS method was successfully applied for determination of fipronil and its metabolites in egg samples.

Design of thermosensitive polymer‐coated magnetic mesoporous silica nanocomposites with a core‐shell‐shell structure as a magnetic/temperature dual‐responsive drug delivery vehicle

AbstractA stimuli‐responsive nanocomposite with a core‐shell‐shell structure consisting of iron oxide (Fe3O4) nanoparticles as core, mesoporous silica as middle shell, and poly(N‐isopropyl acrylamide‐co‐acrylic acid) (P[NIPAAm‐co‐AAc]) as an exterior shell with thermo‐responsivity properties was synthesized to be used as a magnetic/temperature responsive drug delivery system. The structure, morphology, and size of P(NIPAAm‐co‐AAc)‐coated mesoporous silica embedded magnetite nanoparticles (P(NIPAAm‐co‐AAc)@mSiO2@Fe3O4) were characterized by XRD, FTIR, and TEM analyses. Also, the heating ability of mesoporous silica‐coated Fe3O4 nanoparticles, and P(NIPAAm‐co‐AAc)@mSiO2@Fe3O4 nanocomposites was investigated under the exposure of an alternating magnetic field (AMF). The results indicated that the prepared nanocomposites could generate enough heat for hyperthermia applications. Moreover, the magnetic/temperature‐responsive drug release behavior of P(NIPAAm‐co‐AAc)@mSiO2@Fe3O4 nanocomposites loaded with fluorouracil (5‐FU) was studied under the exposure of the AMF (frequency = 120 kHz, and amplitude = 22 kA m−1), as well as two different temperatures (37°C and 45°C). The results showed that only 7.8% of the drug could be released after 20 h at 37°C (below the LCST of the copolymer). In contrast, by increasing the temperature of release medium up to 45°C (above the LCST of the copolymer), the amount of released drug was increased up to 47%. Moreover, by exposing the prepared nanocomposite to a safe AMF, a burst release of drug was observed, indicating the excellent responsivity of the carrier to an external magnetic field. These results proved that the obtained nanocomposite has a great performance to be used as a magnetic/temperature‐sensitive drug carrier for advanced drug delivery applications.

High removal rate and selectivity of Hg(II) ions using the magnetic composite adsorbent based on starch/polyethyleneimine

In this work, we developed a cheap and effective magnetic composite adsorbent (MSP) by introducing starch/polyethyleneimine to the surface of magnetic mesoporous silica. The prepared material was characterized by FT-IR, TG, XRD, SEM and TEM to determine its composition and morphology. Adsorption experiment showed that the removal rate of mercury(II) and adsorption capacity could reach 97.87% and 244.87 mg/g after 150 min. The kinetic study indicated that the adsorption data fitted well with the pseudo-second-order model, and the adsorption equilibrium data belonged to the Langmuir model. Meanwhile, the study of coexisting ions showed that MSP had a highly selective adsorption of mercury(II), and the adsorption capacity of the adsorbent after five times accounted for 91.27% of the initial adsorption capacity, which indicated magnetic nanomaterial manifested excellent selectivity and reutilization for mercury(II) adsorption. All in all, a feasible methods and cheap materials were implied to prepare a new magnetic composite adsorbent, and it will be a candidate for uptake of mercury(II) ions from industrial wastewater.

Novel Magnetic Mesoporous Micro‐nano Particles Immobilized with Palladium Complex: An Efficient and Recyclable Catalyst for Suzuki‐Miyaura Cross‐Coupling Reaction in Ethanol

AbstractNovel and stable magnetic mesoporous silica micro‐nano catalyst immobilized with palladium complex of N‐heterocyclic carbene were readily synthesized with a well‐designed process, which exhibited extremely high catalytic activity in Suzuki‐Miyaura cross‐coupling reactions in ethanol. The double‐template micelle system was used to prepare the mesoporous silica coating layer, which has the characteristics of a large specific surface area and adjustable pore size. Remarkably, the catalyst could be recycled 14 times without significant decrease in activity. It reflects the effectiveness of our strategy of combining the activity of N‐heterocyclic carbene (NHC) with specificity of the mesoporous silica to improve the catalyst catalytic activity and load stability.

Fluorescence resonance energy transfer monitoring of pH-responsive doxorubicin release from carbon dots/aptamer functionalized magnetic mesoporous silica.

Aim: To develop a novel theranostic nanoplatform for simultaneous fluorescent monitoring and stimuli-triggered drug delivery. Materials & methods: Different microscopic and spectroscopic techniques were used for the characterization of nanocarriers. MCF-7 and human umbilical vein endothelial cell lines were cultured and treated with different doses of doxorubicin-loaded nanocarriers. The cell viability and drug release were studied using MTT assay and fluorescence microscopy. Results: Biocompatible and mono-disperse nanocarriers represent hollow and mesoporous structures with the calculated surface area of 552.83m2.g-1, high magnetic activity (12.6 emu.g-1), appropriate colloidal stability and high drug loading capacity (up to 61%). Conclusion: Taxane-based carbon dots act as the pH-responsive gatekeepers for the controlled release of doxorubicin into cancer cells and provide a fluorescence resonance energy transfer system for real-time monitoring of drug delivery.

Interfacially Super‐Assembled Asymmetric and H2O2 Sensitive Multilayer‐Sandwich Magnetic Mesoporous Silica Nanomotors for Detecting and Removing Heavy Metal Ions

AbstractAsymmetric 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.

Determination of polymer additives in foods and drinks packed with plastic by amino group modified magnetic mesoporous silica microspheres coupled with high performance liquid chromatography

The polymer additives may migrate out from polymer plastics into foods and drinks and their potential risk should not be ignored. In this study, amino group modified magnetic mesoporous silica microspheres were prepared by an in situ method. The magnetic microspheres as adsorbent of magnetic solid-phase extraction (MSPE) were coupled with high performance liquid chromatography (HPLC) to determine nine kinds of polymer additives including antioxidants and ultraviolet absorbers. An excellent linearity (0.9999 ≥ R 2 ≥ 0.9994) was at the range of 1.25–1000 ng/mL under optimized conditions. The limits of detection (LODs) and quantification were 0.01–0.09 ng/mL and 0.02–0.30 ng/mL, respectively, for the nine polymer additives, which was lower than those previously reported. This method can be used for the quantitative determination of the migration levels of seven kinds of polymer additives in real foods and drinks packed with plastics.

Orienting the Pore Morphology of Core-Shell Magnetic Mesoporous Silica with the Sol-Gel Temperature. Influence on MRI and Magnetic Hyperthermia Properties.

The controlled design of robust, well reproducible, and functional nanomaterials made according to simple processes is of key importance to envision future applications. In the field of porous materials, tuning nanoparticle features such as specific area, pore size and morphology by adjusting simple parameters such as pH, temperature or solvent is highly needed. In this work, we address the tunable control of the pore morphology of mesoporous silica (MS) nanoparticles (NPs) with the sol-gel reaction temperature (Tsg). We show that the pore morphology of MS NPs alone or of MS shell covering iron oxide nanoparticles (IO NPs) can be easily tailored with Tsg orienting either towards stellar (ST) morphology (large radial pore of around 10 nm) below 80 °C or towards a worm-like (WL) morphology (small randomly oriented pores channel network, of 3–4 nm pore size) above 80 °C. The relaxometric and magnetothermal features of IO@STMS or IO@WLMS core shell NPs having respectively stellar or worm-like morphologies are compared and discussed to understand the role of the pore structure for MRI and magnetic hyperthermia applications.

Structure Engineering of Yolk-Shell Magnetic Mesoporous Silica Microspheres with Broccoli-Like Morphology for Efficient Catalysis and Enhanced Cellular Uptake.

Yolk-shell magnetic mesoporous microspheres exhibit potential applications in biomedicine, bioseparation, and catalysis. Most previous reports focus on establishing various interface assembly strategies to construct yolk-shell mesoporous structures, while little work has been done to control their surface topology and study their relevant applications. Herein, a unique kind of broccoli-like yolk-shell magnetic mesoporous silica (YS-BMM) microsphere is fabricated through a surfactant-free kinetic controlled interface assembly strategy. The obtained YS-BMM microspheres possess a well-defined structure consisting of a magnetic core, middle void, mesoporous silica shell with tunable surface roughness, large superparamagnetism (36.4 emu g-1 ), high specific surface area (174 m2 g-1 ), and large mesopores of 10.9nm. Thanks to these merits and properties, the YS-BMM microspheres are demonstrated to be an ideal support for immobilization of ultrafine Pt nanoparticles (≈3.7nm) and serve as superior nanocatalysts for hydrogenation of 4-nitrophenol with yield of over 90% and good magnetic recyclability. Furthermore, YS-BMM microspheres show excellent biocompatibility and can be easily phagocytosed by osteoclasts, revealing a potential candidate in sustained drug release in orthopedic disease therapy.

Fabrication of the magnetic mesoporous silica Fe-MCM-41-A as efficient adsorbent: performance, kinetics and mechanism

Antibiotics are emerging pollutants and increasingly present in aquaculture and industrial wastewater. Due to their impact on the environment and health, their removal has recently become a significant concern. In this investigation, we synthesized nano zero-valent iron-loaded magnetic mesoporous silica (Fe-MCM-41-A) via precipitation and applied the adsorption of oxytetracycline (OTC) from an aqueous solution. The effects of competing ions such as Na+, Ca2+ and Cu2+ on the adsorption process under different pH conditions were studied in depth to providing a theoretical basis for the application of nanomaterials. The characterization of the obtained material through transmission electron microscopy demonstrates that the adsorbent possesses hexagonal channels, which facilitate mass transfer during adsorption. The loaded zero-valent iron made the magnetic, and was thus separated under an applied magnetic field. The adsorption of OTC onto Fe-MCM-41-A is rapid and obeys the pseudo-second-order kinetic model, and the maximum adsorption capacity of OTC is 625.90 mg g−1. The reaction between OTC and Fe-MCM-41-A was inner complexation and was less affected by the Na+. The effect of Ca2+ on the adsorption was small under acidic and neutral conditions. However, the promotion effect of Ca2+ increased by the increase of pH. Cu2+ decreased the removal efficiencies continuously and the inhibitory effects decrease varied with the increase of pH. We propose that surface complexing, ion-exchange, cationic π-bonding, hydrogen bonding, and hydrophobicity are responsible for the adsorption of OTC onto Fe-MCM-41-A.

Highly effective removal of lead and cadmium ions from wastewater by bifunctional magnetic mesoporous silica

A bifunctionalized magnetic mesoporous silica (NZVI-SH-HMS) material with thiol and nanometer zero-valent iron immobilized on the surface was synthesized at ambient temperature by gel-sol and wet impregnation methods, which was successfully used to remove lead and cadmium ions from aqueous solution. SEM, TEM images and FTIR spectra showed that thiol and NZVI were stable and evenly dispersed onto the surface of HMS. N2 adsorption–desorption isotherms indicated NZVI-SH-HMS owned good porous properties with a large specific surface area (312.84 m2/g) and proper pore size (2.56 nm). XRD and XPS results confirmed the material was superparamagnetic and the main process for removing heavy metals was the formation of Pb3(CO3)2(OH)2, PbS, CdxFe(1-x)(OH)2 and Cd(OH)2. The theoretical maximum adsorption capacity of NZVI-SH-HMS was 487.8 mg Pb(II)/g and 330.0 mg Cd(II)/g, respectively. Adsorption isotherm and kinetics data fitted perfectly to Langmuir isotherm model and followed the pseudo-second-order kinetics. Batch experiments indicated that the main adsorption mechanisms could be precipitation/co-precipitation and surface complexation between the heavy metal ions and the adsorbents. Additionally, NZVI-SH-HMS exhibited excellent adsorption capacities and sorption recyclability in various simulated wastewater (the surface water, tap water, sewage plant wastewater and domestic wastewater), which showed the promising capabilities for the removal of heavy metal ions in actual water environment. These results suggested that the synergistic effects of NZVI and thiol greatly improved the adsorption performance of the bifunctionalized magnetic mesoporous silica materials.

Magnetic Mesoporous Silica Nanoparticles as a Theranostic Approach for Breast Cancer: Loading and Release of the Poorly Soluble Drug Exemestane

Magnetic Mesoporous Silica Nanoparticles as a Theranostic Approach for Breast Cancer: Loading and Release of the Poorly Soluble Drug Exemestane