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Background and Aim: Escherichia coli (E.coli) is an essential bacterial indicator in the control of pharmaceutical quality and other similar fields. There are some biosensors designed for its detection based on electrochemical transduction methods. A biosensor with reduced graphene oxide was modified. Traditional methods are time-consuming and high prices, so in this study a new biosensor with modification of reduced graphene oxide (rGO) as a kind of carbon composition on glassy carbon electrode (GCE) with Au Nanoparticles (Au NPs) decoration was used for E. coli detection. Materials and Methods: Reduced graphene oxide (rGO) modified on glassy carbon electrode (GCE) and chronoamperometric and reduction methods were used for Au NPs decoration and it was completed with polyclonal E. coli antibody and 0.5 W/V% Bovine Serum Albumin (BSA) solution. Morphology and structure of rGO and Au NPs in GCE/rGO/Au NPs/ E. coli polyclonal antibody/ BSA biosensor were verified by SEM (Scanning Electron Microscope) during modification steps. E. coli detection in dissimilar samples was performed by Square-Wave Voltammetry (SWV) and Cyclic Voltammetry (CV) techniques which were set in 0.1M phosphate buffer solution (PBS) (pH 7.4) mixed with 0.5mM acetaminophen. In comparison with the biosensor, the classical method of detection was performed with serial dilutions of E. coli ATCC 8739 (1×101-1×108 CFU/mL) which was cultured on media. Results: Despite the two methods used to stabilize Au NPs, scanning electron microscope (SEM) images showed that the current difference did not increase due to gold particles. Its modification had no significant change in current and it was not a successful experiment for E.coli detection. Conclusion: Compared with the plate method, biosensors couldn't substitute with conventional methods for E. coli detection. [ABSTRACT FROM AUTHOR]

Blood clots are one of the leading causes of death as a consequence of cardiovascular disease in the first place. Design and synthesis of new thrombolytic drugs is aimed at the prevention of side effects one of the important target in medicine. Herein, we report a novel nano-composite prepared by Urokinase with magnetite nanoparticles (Fe3O4@MCM-41-Urokinase). The magnetic nano-drug was prepared in three steps: (i) preparation of colloidal iron oxide magnetite nanoparticles (Fe3O4 MNPs) with particle size lower than 8.0 nm, (ii) development of an organic–inorganic MCM-41 mesoporous structure on the surface of MNPs (Fe3O4@MCM-41) and (iii) load the Urokinase on synthesized nano-composite surface (Fe3O4@MCM-41-Urokinase). The prepared organic–inorganic magnetic nano-drug was characterized by FT-IR (Fourier transform infrared spectroscopy), XRF (X-ray fluorescence), XRD (X-ray powder diffraction), TEM (Transmission electron microscopy) and VSM (Vibrating-sample magnetometer). The TEM image show, a large number of magnetite nanoparticles (2–5 nm) are dispersed in the structure of the siliceous mesoporous. shows excellent activity in the drug delivery in rats. The synthesized nano drug showed good stability to environmental factors. The drug delivery was evaluated in a group of 16 rats, the results showed that drug delivery in the presence of a magnetic field was successfully carried out. [ABSTRACT FROM AUTHOR]

Taguchi method was applied to optimize cloud point extraction (CPE) conditions for preconcentration and determination of trace amounts of copper by UV-Vis spectrophotometry. Briefly, the copper ions formed complexes with neocuproine in aqueous solution; then, Triton X-114 (0.15%, w/v) was added and phase separation occurred upon heating to 60°C. The copper complexes were preconcentrated into the small volume of the surfactant-rich phase; after centrifugation, the surfactant-rich phase was diluted with methanol and absorbance was measured at 455 nm. The main factors affecting the CPE were evaluated and optimized with Taguchi orthogonal array design ([OA.sub.25]). Under the optimum conditions, the calibration curve was linear in the range 2-500 µg/L ([r.sup.2] > 0.997). The limit of detection and preconcentration factor were 1.8 µg/L and 37.2, respectively. The applicability of the proposed method was successfully confirmed by preconcentration and determination of trace amounts of copper in water samples and satisfactory results were obtained. Keywords: copper, neocuproine, Triton X-114, cloud point extraction DOI: 10.1134/S1061934814030125, Copper is both vital and toxic for many biological systems [1, 2]. It plays an important role in environmental and health studies. It is an essential micro-nutrient required in growth [...]

Lipopolysaccharide (LPS) is a component of Gram‐negative bacteria's outer membrane that, when released into aqueous solutions, can have devastating consequences for human health. In this study, sulfonic acid‐functionalized mesoporous silica nanocomposites bound to polymixin‐B was synthesized and their functionality to absorb the bacterial LPS from human serum was investigated. Briefly, Pseudomonas aeruginosa was isolated from burn wounds and its LPS was extracted. Then, Mesoporous MCM‐41 nanocomposites were fabricated and functionalized with the sulfonic acid groups. Finally, nanocomposites were used to extract LPS from human serum and statistical data were analyzed using the Taguchi method. Extraction of bacterial LPS with a modified method, optimization of factors affecting the extraction of endotoxin using Taguchi method, introduction of new nano‐composites with nanometer pores and obtaining results with 96 % effectiveness in removing LPS in LAL and MTT tests were the most important findings. The obtained calibration curve was linear in the ranges of 1–300 μg L‐1 with reasonable linearity (r2>0.998). The limit of detection (LOD) based on S/N=3 was 0.03 μg L‐1 for 10 mL sample volumes. [ABSTRACT FROM AUTHOR]

In this article the preparation of Fe3O4@MCM-41@NH-SO3H, a new sulfonated magnetic mesoporous nanocomposite, is reported. The introduced catalyst is structurally based on MCM-41 as the mesoporous support in which besides having all the unique properties, has a limited acidity so its catalytic strength was favorably improved via acidic functionalization as an applicable and efficient procedure. The accuracy of the specified formula attributed to the synthesized nanocomposite was verified using FT-IR, XRD, BET, TEM, VSM and TGA techniques and also pH analysis. In continue, the influence of this reagent on the formyl protection of amines and alcohols was investigated. As predicted, Fe3O4@MCM-41@NH-SO3H showed considerable efficiency in the promotion of the studied reactions. [ABSTRACT FROM AUTHOR]

The present article reports the synthesis of a new magnetic mesoporous nanocomposite with core–shell structure, formulated as Fe3O4@MCM‐41@ZrCl2. The prepared reagent was successfully characterized using different types of methods. The combination of unique properties of MCM‐41 as an inimitable mesoporous compound, satisfying magnetic nature of the Fe3O4 magnetic nanoparticles and substantial catalytical applications of zirconium, caused the favorable efficiency of the intended nanocomposite in the synthesis of 1‐(benzothiazolylamino)phenylmethyl‐2‐naphthols via a multicomponent condensation reaction of 2‐aminobenzothiazole, 2‐naphthol, and aromatic aldehydes in absence of solvent in good to high yields (70–90%). Green conditions of the reactions, easy separation, practicability, product purity, reusability of the catalyst, affordability, and environmentally profits are the considerable advantages of this protocol. [ABSTRACT FROM AUTHOR]

Comparison of the efficiency of Fe SB 3 sb O SB 4 sb @MCM-41@NH-SO SB 3 sb H with other reported catalysts in the reaction of aniline and 1,2-phenylendiamine with triethyl orthoformate. 0This work ht To probe the reusability of the recovered catalyst, the reaction of aniline with triethyl orthoformate under the optimized reaction conditions was investigated. A comparison between the results from the reaction of aniline and 1,2-phenylendiamine with triethyl orthoformate using our new catalyst and some other reported ones is presented in Table 4. Building on the basis of our previous studies on magnetic, mesoporous and acidic catalysts[[1]] we wish to report a new nanocomposite of Fe SB 3 sb O SB 4 sb (as the magnetic core) and the mesoporous material known as Mobil Composition of Matter No. 41 (MCM-41) (as the mesostructured layer) containing SO SB 3 sb H functionalities. [Extracted from the article]

In the present study, the synthesis of electromagnetic absorber hybrid organic-inorganic mesoporous Al&Fe2O3@NO2-Ph-PMO nanocomposite as a new class of nanoenergetic materials with large density of NO2 groups is investigated. For this purpose, the Al&Fe2O3@NO2-Ph-PMO nanocomposite is prepared in five steps: (1) preparation of hybrid organic-inorganic mesoporous Ph-PMO via sol-gel method, (2) incorporation of NO2 moieties on the surface of Ph-PMO by nitration reaction, (3) preparation of iron oxide magnetite nanoparticles (Fe3O4-MNPs) via a chemical precipitation method and thermotransfer to hematite (Fe2O3-MNPs), (4) development of the nanocomposite embedded Fe2O3-MNPs on the surface of hybrid organic-inorganic NO2-Ph-PMO mesoporous structure by ultrasonic method and finally, (5) the preparation and incorporation of Al nanoparticles (as a fuel in thermite reaction) on the surface of Fe2O3@NO2-Ph-PMO using the ultrasound-assisted method which leads to a high energetic nanocomposite propellant, Al&Fe2O3@NO2-Ph-PMO, based superthermite concept. All, the higher loading of the NO2 group on the vast specific surface area of PMO, the electromagnetic absorption property and superthermite character of the nanocomposite are improved and reported in this paper. Finally, the texture and structure of the prepared energetic metastable intermolecular nanocomposite are characterized by FT-IR, XRD, TEM, VSM and N2 sorption analysis. [ABSTRACT FROM AUTHOR]

Fe3O4@MCM‐41@Zr‐MNPs modified with piperazine is easily prepared and characterized using Fourier transform infrared spectroscopy (FT‐IR), X‐ray powder diffraction (XRD), N2 adsorption–desorption, Transmission electron microscopy (TEM), Energy‐dispersive X‐ray (EDX), Vibrating sample magnetometry (VSM) and Thermogravimetric analysis (TGA) techniques. The characterization results showed that Zr highly dispersed in the tetrahedral environment of silica framework and piperazine is successfully attached to the surface of the nanocatalyst in connection with zirconium. The prepared nanosized reagent (10–30 nm), shows excellent catalytic activity in the synthesis of tetrahydro‐4H‐chromene and pyrano[2,3‐d]pyrimidinone derivatives. All reactions are performed under mild and completely heterogeneous reactions conditions in high yields during short reaction times. On the other hand and due to its superparamagnetic nature the catalyst can be easily separated by the application of an external magnetic field and reused for several times. [ABSTRACT FROM AUTHOR]

Background: The Internet of Things (IoT) is one of the most important and widely used technologies in the world. It has improved processes, reduced costs, and increased safety, and productivity. The use of the IoT in the control of electronic equipment, industrial factories, farm centers, and agricultural fields has been very successful leading to an increase in the amount of production and improved quality of products. Drowning is one of the most important issues in safety and health topics, and many studies and technologies have been designed to reduce the death rate caused by drowning. Methods: Using the IoT in drowning by designing sensors and creating a communication platform-based internet in swimming pools, entertainment centers, ships, submarines, etc. through increasing the control and accuracy of safety systems can significantly reduce deaths due to drowning. This technology is important in the following aspects of drowning: i) It improves the performance of safety systems (increasing accuracy and ease of prevention) ii) It reduces the costs (material and spiritual, such as reducing mortality) iii) Creating income for knowledge-based companies (creating a market and producing new equipment) This study was based on the national drowning registry system of Guilan Road Trauma Research Center, Guilan University of Medical Sciences, Rasht, Iran. Results: IoT in drowning refers to the development and use of IoT in drowning prevention equipment and programs. With a strong focus on machine-to-machine communication, big data, and machine learning, it enables control centers to achieve better efficiency and reliability. By using this technology, you can get more accurate information about air quality, water quality, risks, and climate changes to prevent drowning. IoT devices in this application typically span a large geographic area and can also be mobile. Conclusion: The development of IoT-based equipment in the marine transportation system, seashores, swimming pools, etc., especially in developing countries, can reduce drowning-related deaths. [ABSTRACT FROM AUTHOR]

In this study, magnetite nanoparticles with particle size lower than 47 nm were synthesized and were applied for preconcentration of Pb2+ ions from aqueous solutions. To preconcentrate the Pb2+ ions, the surface of the synthesized nano particles was modified with sodium dodecyl sulfate (SDS) as an anionic surfactant. A new chelating agent (2-((E)-2-amino- 4,5-dinitrophenylimino)methyl)phenol) was synthesized and used to form a very stable complex with Pb2+ ions. The lead ions formed complexes and were quantitatively extracted with SDS-coated magnetite nanoparticles. After magnetic separation of adsorbent, the adsorbent was eluted with 0.5% (v/v) HCl in dimethyl sulfoxide (DMSO) prior to analysis by flame atomic absorption spectrometry (FAAS). Orthogonal array design (OAD) was used to study and optimize the different experimental parameters. Under the optimum conditions, enhancement factor up to 63.5 was achieved for extraction from only 10 mL of sample solution and the relative standard deviation (RSD %) of the method was lower than 2.8%. The obtained calibration curve was linear in the range of 1-300 μg L-1 with reasonable linearity (r² > 0.998). The limit of detection (LOD) based on S/N = 3 was 0.04 μg L-1 for 10 mL sample volumes. Finally, applicability of the proposed method was successfully confirmed by preconcentration and determination of trace amounts of lead ions in environmental samples and satisfactory results were obtained. [ABSTRACT FROM AUTHOR]

This article presents a comprehensive study of the development of a novel nanocomposite comprising core-shell Fe 3 O 4 @MCM-41 with superparamagnetic properties and hydroxyapatite (HAp). The nanocomposite serves as a pH-responsive nanocarrier, offering an efficient injectable dosage for teriparatide (PTH (1-34)) delivery. The aim is to address the limitations associated with drug-induced side effects, precautionary measures, and frequent injections. The nanocomposites, as prepared, were characterized using techniques including X-ray diffraction, Fourier transform infrared, zeta potential, dynamic light scattering, VSM, scanning electron microscopy, and transmission electron microscopy. The nanocomposites' average crystallite diameter was determined to be 27 ± 5 nm. The hydrodynamic size of the PTH (1-34)-loaded nanocarrier ranged from 357 to 495 nm, with a surface charge of -33 mV. The entrapment and loading efficiencies were determined to be 73% and 31%, respectively. All of these findings collectively affirm successful fabrication. Additionally, in vivo medication delivery was investigated using the HPLC method, mirroring the in vitro tests. Utilizing the dialysis approach, we demonstrated sustained-release behavior. PTH (1-34) diffusion increased as the pH decreased from 7.4 to 5.6. After 24 h, drug release was higher at acidic pH (88%) compared to normal pH (43%). The biocompatibility of the PTH (1-34)-loaded nanocarrier was assessed using the MTT assay employing the NIH3T3 and HEK-293 cell lines. The results demonstrated that the nanocarrier not only exhibited nontoxicity but also promoted cell proliferation and differentiation. In the in vivo test, the drug concentration reached 505 μg within 30 min of exposure to the magnetic field. Based on these findings, the Fe 3 O 4 @MCM-41/HAp/PTH (1-34) nanocomposite, in combination with a magnetic field, offers an efficient and biocompatible approach to enhance the therapeutic effect of osteogenesis and overcome drug limitations., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Immobilized NaHSO₄ on core/shell phenylene bridged periodic mesoporous organosilica magnetic nanoparticles (Fe₃O₄@Ph-PMO-NaHSO₄) as a new acidic magnetically separable nanocatalyst was successfully prepared in three steps: (i) preparation of Fe₃O₄ nanoparticles by a precipitation method, (ii) synthesis of an organic-inorganic periodic mesoporous organosilica structure with phenyl groups on the surface of Fe₃O₄ magnetic nanoparticles (MNPs) and (iii) finally adsorption of NaHSO₄ on periodic mesoporous organosilica (PMO) network. The prepared organic-inorganic magnetic reagent was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), N₂ adsorption-desorption and energy-dispersive X-ray (EDX) techniques. Finally, it was used as a reusable and new catalyst to promote the synthesis of tetrahydrobenzo[ b ]pyran and pyrano[2,3- d ]pyrimidinone derivatives as important biologically active compounds. Eco-friendly protocol, high yields, short reaction times and easy and quick isolation of the products are the main advantages of this procedure.