MgSiO3 Fiber Membrane Scaffold with Triggered Drug Delivery for Osteosarcoma Synergetic Therapy and Bone Regeneration.

In this research, a novel MgSiO3 fiber membrane (MSFM) loaded with indocyanine green (ICG) and doxorubicin (DOX) was prepared. Because of MgSiO3's unique lamellar structure composed of a silicon-oxygen tetrahedron, magnesium ion (Mg2+) moves easily and can be further replaced with other cations. Therefore, because of the positively charged functional group of ICG, MSFM has a rather high drug loading for ICG. In addition, there is electrostatic attraction between DOX (a cationic drug) and ICG (an anionic drug). Hence, after loading ICG, more DOX can be adsorbed into MSFM because of electrostatic interaction. The ICG endows the MSFM outstanding photothermal therapy (PTT) performance, and DOX as a chemotherapeutic drug can restrain tumor growth. On the one hand, H+ exchanged with the positively charged DOX based on the MgSiO3 special lamellar structure. On the other hand, the thermal effect could break the electrostatic interaction between ICG and DOX. Based on the above two points, both tumor acidic microenvironment and photothermal effect can trigger DOX release. What's more, in vitro and in vivo antiosteosarcoma therapy evaluations displayed a superior synergetic PTT-chemotherapy anticancer treatment and excellent biocompatibility of DOX&ICG-MSFM. Finally, the MSFM was proven to greatly promote cell proliferation, differentiation, and bone regeneration performance in vitro and in vivo. Therefore, MSFM provides a creative perspective in the design of multifunctional scaffolds and shows promising applications in controlled drug delivery, antitumor performance, and osteogenesis.

Adsorption of cadmium (II) on organic xerogel microspheres: effect of adding sepiolite or vermiculite and operating conditions on the adsorption capacity.

The organic xerogel (OX) was synthesized through sol-gel polymerization of formaldehyde and resorcinol in inverse emulsion using Na2CO3 as a catalyst. Meanwhile, OX containing sepiolite (OX-Sep) and vermiculite (OX-Ver) were prepared similarly to OX but adding clays during synthesis. All materials were mesoporous and presented spherical morphology, and the surface of these materials exhibited an acidic character because the concentration of acidic sites was higher than those of basic sites. Cd(II) adsorption from aqueous solutions onto OX, OX-Sep, and OX-Ver was examined, and the OX-Sep showed the highest adsorption capacity towards Cd(II) of 189.7 mg/g, being 1.5, 2, and 36 times higher than that of OX-Ver, OX, and Sep. The OX-Sep capacity for adsorbing Cd(II) was significantly lessened by decreasing the pH from 7 to 4 and raising the ionic strength from 0.01 N to 0.1 N. This trend was ascribed to electrostatic attraction between the Cd+2 in water and the negatively charged surface of OX-Sep. Besides, desorption studies at pH 4 showed that the average desorption percentage of Cd(II) adsorbed on OX-Sep was 80%. The characterization results and the effect of the operating conditions on the adsorption capacity proved that electrostatic attraction and cation exchange play a crucial role in the adsorption mechanism.

Evaluation of the Effectiveness of Innovative Sorbents in Restoring Enzymatic Activity of Soil Contaminated with Bisphenol A (BPA).

As part of the multifaceted strategies developed to shape the common environmental policy, considerable attention is now being paid to assessing the degree of environmental degradation in soil under xenobiotic pressure. Bisphenol A (BPA) has only been marginally investigated in this ecosystem context. Therefore, research was carried out to determine the biochemical properties of soils contaminated with BPA at two levels of contamination: 500 mg and 1000 mg BPA kg-1 d.m. of soil. Reliable biochemical indicators of soil changes, whose activity was determined in the pot experiment conducted, were used: dehydrogenases, catalase, urease, acid phosphatase, alkaline phosphatase, arylsulfatase, and ß-glucosidase. Using the definition of soil health as the ability to promote plant growth, the influence of BPA on the growth and development of Zea mays, a plant used for energy production, was also tested. As well as the biomass of aerial parts and roots, the leaf greenness index (SPAD) of Zea mays was also assessed. A key aspect of the research was to identify those of the six remediating substances-molecular sieve, zeolite, sepiolite, starch, grass compost, and fermented bark-whose use could become common practice in both environmental protection and agriculture. Exposure to BPA revealed the highest sensitivity of dehydrogenases, urease, and acid phosphatase and the lowest sensitivity of alkaline phosphatase and catalase to this phenolic compound. The enzyme response generated a reduction in the biochemical fertility index (BA21) of 64% (500 mg BPA) and 70% (1000 mg BPA kg-1 d.m. of soil). The toxicity of BPA led to a drastic reduction in root biomass and consequently in the aerial parts of Zea mays. Compost and molecular sieve proved to be the most effective in mitigating the negative effect of the xenobiotic on the parameters discussed. The results obtained are the first research step in the search for further substances with bioremediation potential against both soil and plants under BPA pressure.

Promoting neurovascularized bone regeneration with a novel 3D printed inorganic-organic magnesium silicate/PLA composite scaffold.

Critical-size bone defect repair presents multiple challenges, such as osteogenesis, vascularization, and neurogenesis. Current biomaterials for bone repair need more consideration for the above functions. Organic-inorganic composites combined with bioactive ions offer significant advantages in bone regeneration. In our work, we prepared an organic-inorganic composite material by blending polylactic acid (PLA) with 3-aminopropyltriethoxysilane (APTES)-modified magnesium silicate (A-M2S) and fabricated it by 3D printing. With the increase of A-M2S proportion, the hydrophilicity and mineralization ability showed an enhanced trend, and the compressive strength and elastic modulus were increased from 15.29 MPa and 94.61 MPa to 44.30 MPa and 435.77 MPa, respectively. Furthermore, A-M2S/PLA scaffolds not only exhibited good cytocompatibility of bone marrow mesenchymal stem cells (BMSCs), human umbilical vein endothelial cells (HUVECs), and Schwann cells (SCs), but also effectively promoted osteogenesis, angiogenesis, and neurogenesis in vitro. After implanting 10% A-M2S/PLA scaffolds in vivo, the scaffolds showed the most effective repair of cranium defects compared to the blank and control group (PLA). Additionally, they promoted the secretion of proteins related to bone regeneration and neurovascular formation. These results provided the basis for expanding the application of A-M2S and PLA in bone tissue engineering and presented a novel concept for neurovascularized bone repair.

Effect and mechanism of coexistence of microplastics on arsenate adsorption capacity in water.

Arsenic pollution control technology in water was important to ensure environmental health and quality safety of agricultural products. Therefore, the adsorption performance of three adsorbents for chitosan, sepiolite, and Zeolitic Imidazolate Framework-8 (ZIF-8) were investigated in arsenate contaminated water. The results revealed that the adsorption capacity of ZIF-8 was higher than that of chitosan and sepiolite. The analysis of adsorption isotherm models showed that the behavior of ZIF-8 was more consistent with the Langmuir model. Furthermore, the adsorption mechanisms of three adsorbents for arsenate were investigated by Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The analysis of FTIR showed that ZIF-8 maintained the stability of the interaction with arsenate by forming As-O chemical bonds. However, the effect of chitosan and sepiolite with arsenate was mainly physical adsorption. The analysis of XPS showed that the absorption of ZIF-8 with arsenate involved metal sites and nitrogen through the characteristic peak and the change of the binding energy. Furthermore, the impact of microplastics as a widespread coexistence pollutant in the water on adsorbent performance was investigated. The results indicated that the adsorption capacity of ZIF-8 was almost not affected by microplastics. The maximum adsorption amount of arsenate was changed from 73.45 mg/g to 81.89 mg/g. However, the maximum adsorption amount of chitosan and sepiolite decreased by 31.4 % and 11.6 %, respectively. The analysis of FTIR and XPS revealed that ZIF-8 enhances arsenate adsorption by forming N-O-As bonds in the presence of microplastics. This study provides scientific evidence for the management of arsenate pollution in water bodies, especially in complex water bodies containing microplastics.

Assessment of chromite ore wastes for methylene blue adsorption: Isotherm, kinetic, thermodynamic studies, ANN, and statistical physics modeling.

This research investigates the adsorption potential of chrysotile and lizardite, two minerals derived from chromite ore wastes, for the uptake of Methylene Blue (MB) dye from waste streams. The characterization of these minerals involves XRD, XRF, FTIR, and SEM. Results confirm the dominance of polymorphic magnesium silicate minerals, specifically chrysotile and lizardite, in the samples. The FTIR spectra reveal characteristic vibration bands confirming the presence of these minerals. The SEM analysis depicts irregular surfaces with broken and bent edges, suggesting favorable morphologies for adsorption. N2 adsorption-desorption isotherms indicate mesoporous structures with Type IV pores in both adsorbents. The Central Composite Design approach is employed to optimize MB adsorption conditions, revealing the significance of contact time, adsorbent mass, and initial MB concentration. The proposed models exhibit high significance, with F-values and low p-values indicating the importance of the studied factors. Experimental validation confirms the accuracy of the models, and the optimum conditions for MB adsorption are determined. The influence of solution acidity on MB uptake is investigated, showing a significant enhancement at higher pH values. Isothermal studies indicate Langmuir and Freundlich models as suitable descriptions for MB adsorption onto chrysotile and lizardite. The maximum adsorption capacities of MB for chrysotile and lizardite were found to be 352.97 and 254.85, respectively. Kinetic studies reveal that the pseudo-first-order model best describes the adsorption process. Thermodynamic analysis suggests an exothermic and spontaneous process. Statistical physics models further elucidate the monolayer nature of adsorption. Additionally, an artificial neural network is developed, exhibiting high predictive capability during training and testing stages. The reusability of chrysotile and lizardite is demonstrated through multiple regeneration cycles, maintaining substantial adsorption potential. Therefore, this research provides comprehensive insights into the adsorption characteristics of chrysotile and lizardite, emphasizing their potential as effiective and reusable sorbents for MB uptake from wastewater.

A New Perspective on Adsorbent Materials Based Impregnated MgSiO3 with Crown Ethers for Palladium Recovery.

The study of new useful, efficient and selective structures for the palladium ions' recovery has led to the development of a new series of macromolecules. Thus, this study presents a comparative behavior of two crown benzene ethers that modify the magnesium silicate surface used as adsorbent for palladium. These crown ethers are dibenzo18-crown-6 (DB18C6) and dibenzo 30-crown-10 (DB30C10). The obtained materials were characterized by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX) and Fourier-transform infrared spectroscopy (FT-IR). The specific surface area (BET) and point of zero charge (PZC) of the two materials were determined. The palladium ions' recovery from synthetic aqueous solutions studies aimed to establish the adsorption mechanism. For this desideratum, the kinetic, equilibrium and thermodynamic studies show that MgSiO3-DB30C10 have a higher adsorption capacity (35.68 mg g-1) compared to MgSiO3-DB18C6 (21.65 mg g-1). Thermodynamic studies highlight that the adsorption of Pd(II) on the two studied materials are spontaneous and endothermic processes. The positive values of the entropy (ΔS0) suggest that the studied adsorption processes show a higher disorder at the liquid/solid interface. Desorption studies were also performed, and it was found that the degree of desorption was 98.3%.

Preparation, optimization, and characterization of chitosan-sepiolite nanocomposite films for wound healing.

In this study, a series of chitosan-sepiolite (CS-SEP) nanocomposites films were prepared by using a conventional solution casting method. The effect of sepiolite on physicochemical and biological properties of the prepared nanocomposite films was studied by various techniques such as Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and x-ray diffraction (XRD) to name a few. In WCA measurements, the decrease of contact angle from 78.51° (CS) to 71.29° (CS7SEP3) reaffirms the water holding nature of sepiolite, which enables to create moist environment essentially required for wound healing. Further, addition of sepiolite tremendously increased WVTR, folding endurance, porosity, and blood clotting ability of the prepared nanocomposites. Furthermore, CS-SEP nanocomposite films exhibit better antibacterial activity than that of chitosan against gram positive (B. subtilis) and gram negative bacteria (E. coli). Moreover, the percentage of hemolysis and degradation study indicated that the prepared nanocomposite films were non-hemolytic in nature and decomposed nearly 40% in four weeks. In addition, cytotoxicity assay showed that the prepared nanocomposite film i.e. CS7SEP3 exhibited better cell viability and cell proliferation rate against L929 mouse fibroblast cells as compared to CS and hence, the prepared nanocomposite film can be used as a promising candidate for wound management.

Development and characterization of PVA-starch incorporated with coconut shell extract and sepiolite clay as an antioxidant film for active food packaging applications.

An active antioxidant film was fabricated by using polyvinyl alcohol (PVA) and corn starch (ST) and incorporated with and 3, 5, 10, and 20% (v/v) coconut shell extract (CSE) and sepiolite clay (SP) for the first time. The microstructure and physical properties of prepared films were characterized and examined. The addition of sepiolite clay to PVA improved the elongation break 15.57 to 69.24%, and water vapor permeability increased with the addition of CSE. In addition to CSE to films, the antioxidant activity properties of the films were enhanced up to 80%. Further, increasing the amount of CSE slightly affected the color of the active films. The thermal properties of films were enhanced with the addition of CSE and SP. The dispersion of SP in the PVA matrix was affected by an increase in CSE concentration in the PVA matrix. Remarkably, PVA-ST film-based sachets successfully improved the oxidative stability of packaged soybean oil. Our results suggest PVA-ST film containing CSE and sepiolite clay can be utilized as a novel antioxidant packaging material in the food processing industry.

A chitosan-based composite for adsorption of uranyl ions; mechanism, isothems, kinetics and thermodynamics.

The present paper describes a green and cost-effective approach to investigate chitosan-sepiolite (Ch-Sep) composite as an adsorbent for removal of UO22+ ions in aqueous solution. The Ch-Sep composite was prepared as a beads using with two cross-linking agents: tripolyphosphate (TPP) and epichlorohydrin (ECH). Their adsorption properties for the removal of UO22+ ions in aqueous solution by batch experimental conditions were studied. The adsorptive removal processes of UO22+ ions from aqueous solution were evaluated by Langmuir, Freundlich and Dubinin-Radushkevich isotherm models, and was found to be perfectly fit to the Langmuir model (R2 = 0.971). The maximum adsorption capacity was 0.220 mol kg-1 at 25 °C from Langmuir isotherm model. Adsorption energy was 12.1 kJ mol-1 indicating that the adsorption process was chemical. The adsorption kinetics followed the pseudo second order and intra particle diffusion models. The thermodynamics parameters of UO22+ ions removal from aqueous solution was confirmed spontaneous, endothermic and possible at higher temperatures behavior of adsorption process. The adsorption mechanism of UO22+ ions onto Ch-Sep composite beads was investigated by FT-IR and SEM analysis. These findings revealed the effectiveness and potential of the newly synthesized Ch-Sep composite beads for the removal of UO22+ ions.

Mg,Si-Co-Substituted Hydroxyapatite/Alginate Composite Beads Loaded with Raloxifene for Potential Use in Bone Tissue Regeneration.

Osteoporosis is a worldwide chronic disease characterized by increasing bone fragility and fracture likelihood. In the treatment of bone defects, materials based on calcium phosphates (CaPs) are used due to their high resemblance to bone mineral, their non-toxicity, and their affinity to ionic modifications and increasing osteogenic properties. Moreover, CaPs, especially hydroxyapatite (HA), can be successfully used as a vehicle for local drug delivery. Therefore, the aim of this work was to fabricate hydroxyapatite-based composite beads for potential use as local carriers for raloxifene. HA powder, modified with magnesium and silicon ions (Mg,Si-HA) (both of which play beneficial roles in bone formation), was used to prepare composite beads. As an organic matrix, sodium alginate with chondroitin sulphate and/or keratin was applied. Cross-linking of beads containing raloxifene hydrochloride (RAL) was carried out with Mg ions in order to additionally increase the concentration of this element on the material surface. The morphology and porosity of three different types of beads obtained in this work were characterized by scanning electron microscopy (SEM) and mercury intrusion porosimetry, respectively. The Mg and Si released from the Mg,Si-HA powder and from the beads were measured by inductively coupled plasma optical emission spectrometry (ICP-OES). In vitro RAL release profiles were investigated for 12 weeks and studied using UV/Vis spectroscopy. The beads were also subjected to in vitro biological tests on osteoblast and osteosarcoma cell lines. All the obtained beads revealed a spherical shape with a rough, porous surface. The beads based on chondroitin sulphate and keratin (CS/KER-RAL) with the lowest porosity resulted in the highest resistance to crushing. Results revealed that these beads possessed the most sustained drug release and no burst release effect. Based on the results, it was possible to select the optimal bead composition, consisting of a mixture of chondroitin sulphate and keratin.

Physicochemical characterization, drug release, and biocompatibility evaluation of carboxymethyl cellulose-based hydrogels reinforced with sepiolite nanoclay.

Polymer-clay nanocomposite hydrogel films (PCNCHFs) were prepared from caboxymethyl cellulose, polyvinylpyrrolidone, agar and nanosepiolite clay (0, 0.3, 0.5, 0.7, 0.9 and 1.5% reinforcement) by treating thermally in a simple, rapid, and inexpensive route. The PCNCHFs and its 5-fluorouracil (FU)-loaded composites (PCNCHFs@FU) were tested for FU release and characterized by FTIR, XRD, FE-SEM, EDX, DSC, and TGA analyses to investigate their structural, morphological, and thermal properties. The nanosepiolite-loaded polymer composites (PCNCHF1 to PCNCHF5) exhibited higher tensile strength than the pristine polymer hydrogel (PCNCHF0); consequently, the thermal properties (glass- and melting-transition) were improved. The PCNCHFs@FU demonstrated prolonged FU release at pH 7.4 for 32 h. The biocompatibility of PCNCHFs was tested against human skin fibroblast (CCDK) cells. The viability of cells exposed to all PCNCHFs was >95% after 72 h of culture. The live/dead assay show the proliferation of fibroblast cells, confirming the biocompatibility of the hydrogels. The pH-sensitive PCNCHFs@FU release could be suitable for drug release in cancer therapy, and the developed PCNCHFs may also be useful for tissue engineering, food packaging, and other biological applications.

Treatment of environmental contamination using sepiolite: current approaches and future potential.

To evaluate the potential of sepiolite-based materials to resolve environmental pollution problems, a study is needed which looks at the whole life cycle of material application, including the residual value of material classified as waste from the exploitation of sepiolite deposits in the region or from its processing and purification. This would also maximize value from the exploitation process and provide new potential for local waste management. We review the geographical distribution of sepiolite, its application in the treatment of potentially toxic elements in soil and across the wider landscape, an assessment of modification and compositional variation of sepiolite-based applications within site remediation and wastewater treatment. The potential of sepiolite-based technologies is widespread and a number of processes utilize sepiolite-derived materials. Along with its intrinsic characteristics, both the long-term durability and the cost-effectiveness of the application need to be considered, making it possible to design ready-to-use products with good market acceptance. From a critical analysis of the literature, the most frequently associated terms associated with sepiolite powder are the use of lime and bentonite, while fly ash ranked in the top ten of the most frequently used material with sepiolite. These add improved performance for the inclusion as a soil or wastewater treatment options, alone or applied in combination with other treatment methods. This approach needs an integrated assessment to establish economic viability and environmental performance. Applications are not commonly evaluated from a cost-benefit perspective, in particular in relation to case studies within geographical regions hosting primary sepiolite deposits and wastes that have the potential for beneficial reuse.

Alginate bionanocomposite films containing sepiolite modified with polyphenols from myrtle berries extract.

Alginate nanocomposite films incorporating sepiolite (Sep) modified with myrtle berries extract (MBE) rich in polyphenols were prepared by solution casting method. The effects of different extract concentrations on the film properties were determined by measuring physicochemical, mechanical and antioxidant properties of the films. Fourier transform infrared (FTIR) spectra indicated that strong interactions between the polyphenols present in the MBE and sepiolite were involved in the films. The results suggested that incorporation of Sep-MBE hybrids into the films improved elongation at break, tensile strength, water vapor and UV barrier properties compared to the control film. The antioxidant activity of the films was significantly improved and raised with increasing content of MBE. The release kinetics results of MBE polyphenols from the active films into alcoholic food simulant indicated that the addition of Sep-MBE hybrids to alginate film is able to slow the release of MBE polyphenols. This study revealed the benefits of incorporation of Sep-MBE hybrids into the alginate films and their potential application as active packaging films or coating material.

Preparation of organic-inorganic chitosan@silver/sepiolite composites with high synergistic antibacterial activity and stability.

Organic-inorganic antibacterial materials chitosan@silver/sepiolite (CTs@Ag/Sep) was prepared by grafting organometallic chelate of chitosan and silver on sepiolite. The prepared samples were characterized, and their antibacterial properties were detected. The carrier sepiolite was beneficial for the thermal stability of the composite material. The utilization of silver was enhanced and its amount of usage could be obviously reduced by introduction of nontoxic chitosan which was benefical for the formation of highly dispersed silver nanoparticles on the CTs@Ag/Sep by the interaction between the silver ion and the plentiful amino and hydroxyl groups on the chitosan, thus improved the antibacterial activities and stability. The average width of the inhibition zone of CTs@Ag/Sep against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) and Aspergillus niger were 51.8, 31.8, and 44.7 mm, respectively. The cytotoxicity of CTs@Ag/Sep was further evaluated with A549 cells, and the results indicated that it exhibited low cytotoxicity to eukaryotic cells.

Make proper surfaces for immobilization of enzymes: Immobilization of lipase and α-amylase on modified Na-sepiolite.

This paper has focused on making suitable carriers for the immobilization of α-amylase from Bacillus subtilis and lipase from Candida rugosa via adsorption on modified Na-sepiolite (SEP). Two modified carriers were prepared by changing the nature of SEP with cetrimonium bromide surfactant at concentrations below the CMC of the surfactant, to produce SEP with monolayer surfactant (MSEP) with hydrophobic properties and above the CMC of the surfactant to produce SEP with bilayer surfactant (BSEP) with hydrophilic properties. The enzymatic activity of immobilized lipase on MSEP (MSEPL) and immobilized α-amylase on BSEP (BSEPA) was successfully tested in the hydrolysis of olive oil and starch. The support modification and immobilization process were characterized by BET, XRD, and SEM techniques. The results demonstrated that the specific activity of MSEPL and BSEPA was 1.74 and 2.28 U/mg, respectively. The remained activity of MSEPL (56.7%) and BSEPA (40.4%) after their incubation at 60 °C for 4 h was much higher than that of free enzymes. The residual activity of MSEPL and BSEPA was 77.4% and 66.7%, after 30 days of storage at 4 °C. The MSEPL and BSEPA also showed good reusability, and their relative activities were 54.0% and 44.2% after ten cycles.

Analysis of particles from hamster lungs following pulmonary talc exposures: implications for pathogenicity.

BACKGROUND: Talc, a hydrous magnesium silicate, often used for genital hygiene purposes, is associated with ovarian carcinoma in case-control studies. Its potential to cause inflammation, injury, and functional changes in cells has been described. A complication of such studies is that talc preparations may be contaminated with other materials. A previous study by (Beck et al. Toxicol Appl Pharmacol 87:222-34, 1987) used a hamster model to study talc and granite dust exposure effects on various biochemical and cellular inflammatory markers. Our current study accessed key materials used in that 1987 study; we re-analyzed the original talc dust with contemporary scanning electron microscopy and energy dispersive x-ray analysis (SEM/EDX) for contaminants. We also examined the original bronchoalveolar lavage (BAL) cells with polarized light microscopy to quantify cell-associated birefringent particles to gain insight into the talc used. RESULTS: SEM/EDX analyses showed that asbestos fibers, quartz, and toxic metal particulates were below the limits of detection in the original talc powder. However, fibers with aspect ratios ≥3:1 accounted for 22% of instilled material, mostly as fibrous talc. Talc (based on Mg/Si atomic weight % ratio) was the most abundant chemical signature, and magnesium silicates with various other elements made up the remainder. BAL cell counts confirmed the presence of acute inflammation, which followed intratracheal instillation. Measurements of cell associated birefringent particles phagocytosis revealed significant differences among talc, granite, and control exposures with high initial uptake of talc compared to granite, but over the 14-day experiment, talc phagocytosis by lavaged cells was significantly less than that of granite. Phagocytosis of talc fibers by macrophages was observed, and birefringent particles were found in macrophages, neutrophils, and multinucleate giant cells in lavaged cells from talc-exposed animals. CONCLUSION: Our data support the contention that talc, even without asbestos and other known toxic contaminants, may elicit inflammation and contribute to lung disease. Our findings support the conclusions of (Beck et al. Toxicol Appl Pharmacol 87:222-34, 1987) study. By analyzing particulate exposures with polarized light microscopy and SEM/EDX, fibrous talc was identified and a distinctive pattern of impaired particulate ingestion was demonstrated.

1,3,5-Triethynylbenzene and melamine as monomers to synthesize three-dimensional network porous aromatic frameworks based silica/florisil for determination of carbendazim and thiabendazole in spinach.

In this study, the new and efficient three-dimensional network porous aromatic frameworks materials called Silica-PAFs-a, Florisil-PAFs-a, Silica-PAFs-b, and Florisil-PAFs-b were first synthesized. The properties of materials were analyzed by five characterization methods. The materials were used as adsorbents in pipette-tip solid-phase extraction for the effective determination of carbendazim and thiabendazole in spinach sample. Meanwhile, the obtained materials were tested by static adsorption and dynamic adsorption. The result showed that the specific surface area of materials greatly increased after introducing three-dimensional network porous aromatic frameworks. Microstructural modification exposed a large number of amino reactive groups that made them have a better adsorption amount for the two targets. The calibration graphs of carbendazim and thiabendazole in methanol were linear over 0.10-300.0 µg/mL, and the limits of detection and quantification were 0.00546 and 0.0182 µg/mL, and 0.00741 and 0.0247µg/mL respectively. A reliable analytical method was developed for recognition targets in spinach sample by Silica-PAFs-b with satisfactory extraction recoveries (96.25 and 100.51%). The proposed method using the material was applied for trace analysis of the carbendazim and thiabendazole residue.

Macro-Microporous Surface with Sulfonic Acid Groups and Micro-Nano Structures of PEEK/Nano Magnesium Silicate Composite Exhibiting Antibacterial Activity and Inducing Cell Responses.

PURPOSE: To improve the surface bio-properties of polyetheretherketone (PEEK)/nano magnesium silicate (n-MS) composite (PC). MATERIALS AND METHODS: The surface of PC was firstly treated by particle impact (PCP) and subsequently modified by concentrated sulfuric acid (PCPS). RESULTS: PCPS surface exhibited not only macropores with sizes of about 150 µm (fabricated by particle impact) but also micropores with sizes of about 2 µm (created by sulfonation of PEEK) on the macroporous walls, and sulfonic acid (-SO3H) groups were introduced on PCPS surface. In addition, many n-MS nanoparticles were exposed on the microporous walls, which formed micro-nano structures. Moreover, the surface roughness and hydrophilicity of PCPS were obviously enhanced as compared with PC and PCP. Moreover, the apatite mineralization of PCPS in simulated body fluid (SBF) was obviously improved as compared with PC. Furthermore, compared with PC and PCP, PCPS exhibited antibacterial performances due to the presence of -SO3H groups. In addition, the responses (eg, adhesion and proliferation as well as differentiation) of bone marrow mesenchymal stem cell of rat to PCPS were significantly promoted as compared with PC and PCP. CONCLUSION: PCPS with macro-microporous surface containing -SO3H groups and micro-nano structures exhibited antibacterial activity and induced cell responses, which might possess large potential for bone substitute and repair.

Clay Composites for Thermal Energy Storage: A Review.

The development of novel materials and approaches for effective energy consumption and the employment of renewable energy sources is one of the current trends in modern material science. With this respect, the number of researches is focused on the effective harvesting and storage of solar energy for various applications. Phase change materials (PCMs) are known to be able to store thermal energy of the sunlight due to adsorption and release of latent heat through reversible phase transitions. Therefore, PCMs are promising as functional additives to construction materials and paints for advanced thermoregulation in building and industry. However, bare PCMs have limited practical applications. Organic PCMs like paraffins suffer from material leakage when undergoing in a liquid state while inorganic ones like salt hydrates lack long-term stability after multiple phase transitions. To avoid this, the loading of PCMs in porous matrices are intensively studied along with the thermal properties of the resulted composites. The loading of PCMs in microcontainers of natural porous or layered clay materials appears as a simple and cost-effective method of encapsulation significantly improving the shape and cyclic stability of PCMs. Additionally, the inclusion of functional clay containers into construction materials allows for improving their mechanical and flame-retardant properties. This article summarizes the recent progress in the preparation of composites based on PCM-loaded clay microcontainers along with their future perspectives as functional additives in thermo-regulating materials.