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Distinct Methodologies to Produce Capped Mesoporous Silica with Hydroxyapatite and the Influence in Intracellular Signaling as Cytotoxicity on Human Umbilical Vein Endothelial Cells.

Bioengineering (Basel) 2021 Sep 12;8(9). Epub 2021 Sep 12.

Laboratory of Synthesis of Novel Radiopharmaceuticals and Nanoradiopharmacy, Nuclear Engineering Institute, Brazilian Nuclear Energy Commission, Rio de Janeiro 21941906, Brazil.

Mesoporous silica has unique properties such as controllable mesoporous structure and size, good biocompatibility, high specific surface area, and large pore volume. For that reason, this material has been broadly functionalized for biomedical applications, such as optical imaging, magnetic resonance imaging (MRI), positron emission tomography (PET), computed tomography (CT), ultrasound imaging, and widely employed as drug delivery systems. In this study, we synthesized fiber-type mesoporous silica capped with hydroxyapatite (ordered SiO-CaO-PO mesoporous silica). Read More

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September 2021

Sonochemical synthesis of porous gold nano- and microparticles in a Rosette cell.

Ultrason Sonochem 2021 Sep 5;79:105744. Epub 2021 Sep 5.

Chemical Engineering Department, Polytechnique Montréal, 2900 Edouard Montpetit Blvd, Montréal H3T 1J4, QC, Canada; Canada Research Chair in Intensified Mechano-Chemical Processes for Sustainable Biomass Conversion, Canada. Electronic address:

We report the synthesis of Au nano- and microparticles that relies on α-D-glucose (CHO) as the reducer and stabilizer in a Rosette cell under 20 kHz ultrasound irradiation. The chemical and physical effects of ultrasonic irradiation on the synthesis were investigated. The results showed that an optimum pH is required for the formation of insoluble Au(0) particles. Read More

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September 2021

5-Fluorouracil loaded magnetic cellulose bionanocomposites for potential colorectal cancer treatment.

Carbohydr Polym 2021 Dec 4;273:118523. Epub 2021 Aug 4.

Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100 Kuala Lumpur, Malaysia; Faculty of Science, Department of Chemistry, University of Hradec Kralove, Hradec Kralove, Czech Republic.

Magnetic polymer nanocomposites are inherently multifunctional and harbor assorted physiochemical actions for applications thereof as novel drug nanocarriers. Herein, FeO-nanoparticles were supported on rice straw cellulose for 5-fluorouracil carrier abbreviated as MC/5-FU for potential colorectal cancer treatments. Several analyses indicated the multifunctional properties of MC/5-FU bionanocomposites. Read More

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December 2021

Prismatic 2.0 - Simulation software for scanning and high resolution transmission electron microscopy (STEM and HRTEM).

Micron 2021 Sep 10;151:103141. Epub 2021 Sep 10.

National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, USA. Electronic address:

Scanning transmission electron microscopy (STEM), where a converged electron probe is scanned over a sample's surface and an imaging, diffraction, or spectroscopic signal is measured as a function of probe position, is an extremely powerful tool for materials characterization. The widespread adoption of hardware aberration correction, direct electron detectors, and computational imaging methods have made STEM one of the most important tools for atomic-resolution materials science. Many of these imaging methods rely on accurate imaging and diffraction simulations in order to interpret experimental results. Read More

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September 2021

Interaction-Free Measurement with Electrons.

Phys Rev Lett 2021 Sep;127(11):110401

Department of Physics, University of Oregon, Eugene, Oregon 97403, USA.

Here, we experimentally demonstrate interaction-free measurements with electrons using a novel electron Mach-Zehnder interferometer. The flexible two-grating electron interferometer is constructed in a conventional transmission electron microscope and achieves high contrast in discrete output detectors, tunable alignment with independently movable beam splitters, and scanning capabilities for imaging. With this path-separated electron interferometer, which closely matches theoretical expectations, we demonstrate electron interaction-free measurements with an efficiency of 14±1%. Read More

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September 2021

Synthesis of bismuth oxyhalide (BiOBr I ) solid solutions for photodegradation of methylene dye.

AAS Open Res 2021 23;4:43. Epub 2021 Aug 23.

Department of Chemical and Forensic Sciences, Botswana International University of Science and Technology, Palapye, Botswana.

The removal of textile wastes is a priority due to their mutagenic and carcinogenic properties.  In this study, bismuth oxyhalide was used in the removal of methylene blue (MB) which is a textile waste. The main objective of this study was to develop and investigate the applicability of a bismuth oxyhalide (BiOBr I ) solid solutions in the photodegradation of MB under solar and ultraviolet (UV) light irradiation. Read More

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Study on the Mechanism of Qigu Capsule in Upregulating NF-B/HIF-1 Pathway to Improve the Quality of Bone Callus in Mice at Different Stages of Osteoporotic Fracture Healing.

Evid Based Complement Alternat Med 2021 13;2021:9943692. Epub 2021 Sep 13.

Shi's Center of Orthopedics and Traumatology, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China.

Objective: The present study intends to investigate the effects and underlying molecular mechanism of Qigu Capsule (QG) on fracture healing in mice with osteoporosis.

Methods: Ten-week-old female C57BL/6 mice were ovariectomized and three weeks later were evaluated for successful modeling. Then, all mice were prepared into models of transverse fracture in the right middle femoral shaft. Read More

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September 2021

An evaluation of allogeneic freeze-dried concentrated growth factors biocompatibilityand.

Biomed Mater 2021 Sep 23. Epub 2021 Sep 23.

Department of Stomatology, the First Dongguan Affiliated Hospital of Guangdong Medical University, Scientific Research Platform, the Second Clinical Medical College, Guangdong Medical University, Dongguan , 523710, CHINA.

This study evaluated the biocompatibility of allogeneic freeze-dried concentrated growth factors (AFD-CGFs) in vitro and in vivo. For the in vitro experiments, bone marrow stem cells (BMSCs) were cultured in 10% fresh allogeneic concentrated growth factors (CGFs). AFD-CGF solution was used as the experimental group, and Dulbecco's modified Eagle medium (DMEM) was used as control. Read More

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September 2021

Fabrication and field emission properties of vertical, tapered GaN nanowires etched via phosphoric acid.

Nanotechnology 2021 Sep 23. Epub 2021 Sep 23.

Advanced Materials Sciences, Sandia National Laboratories, P.O Box 5800, Albuquerque, New Mexico, 87185-5820, UNITED STATES.

The controlled fabrication of vertical, tapered, and high-aspect ratio GaN nanowires via a two-step top-down process consisting of an inductively couple plasma reactive ion etch (ICP-RIE) followed by a hot, 85% H3PO4 crystallographic wet etch is explored. The vertical nanowires are oriented in the [0001] direction and are bound by sidewalls comprising of {336-2} semipolar planes which are at a 12° angle from the [0001] axis. High temperature H3PO4 etching between 60 and 95°C result in smooth semipolar faceting with no visible micro-facets, whereas a 50°C etch reveals a micro-faceted etch evolution. Read More

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September 2021

Hyperbranched polyethylenimine-modified polyethersulfone (HPEI/PES) and [email protected]/PES membranes with enhanced ultrafiltration, antibacterial, and antifouling properties.

Heliyon 2021 Sep 9;7(9):e07961. Epub 2021 Sep 9.

Analytical-Environmental, Membrane Nanotechnology Research Group, Department of Chemical Sciences, University of Johannesburg, P.O. Box 17011, Doornfontein 2028, Johannesburg, South Africa.

This study reports a simple fabrication of polyethersulfone (PES)-based membranes, their characterisation, and application. These membranes are modified with hyperbranched polyethyleneimine (HPEI) and -silver (nAg)-decorated HPEI. These were then compared for filtration, organic fouling, antifouling, and antibacterial properties against the neat PES membrane. Read More

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September 2021

Nanodissection of Selected Viral Particles by Scanning Transmission Electron Microscopy/Focused Ion Beam for Genetic Identification.

Anal Chem 2021 Sep 22. Epub 2021 Sep 22.

Department of Infectious Diseases, Israel Institute for Biological Research, P.O.B 19, Ness Ziona 74100, Israel.

This study presents the development of a new correlative workflow to bridge the gap between electron microscopy imaging and genetic analysis of viruses. The workflow enables the assignment of genetic information to a specific biological entity by harnessing the nanodissection capability of focused ion beam (FIB). This correlative workflow is based on scanning transmission electron microscopy (STEM) and FIB followed by a polymerase chain reaction (PCR). Read More

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September 2021

Monitoring the formation of a colloidal lipid gel at the nanoscale: vesicle aggregation driven by a temperature-induced mechanism.

J Mater Chem B 2021 Sep 22;9(36):7472-7481. Epub 2021 Sep 22.

Department of Surfactants and Nanobiotechnology, Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), C/Jordi Girona 18-26, 08034 Barcelona, Spain.

Colloidal gels made of lipid vesicles at highly diluted conditions have been recently described. The structure and composition of this type of material could be especially relevant for studies that combine model lipid membranes with proteins, peptides, or enzymes to replicate biological conditions. Details about the nanoscale events that occur during the formation of such gels would motivate their future application. Read More

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September 2021

Magnetic Energy Morphing, Capacitive Concept for NiZnCaFeO Nanoparticles Embedded in Graphene Oxide Matrix, and Studies of Wideband Tunable Microwave Absorption.

ACS Appl Mater Interfaces 2021 Sep 22. Epub 2021 Sep 22.

Solid State Research Laboratory, Department of Physics, Burdwan University, Burdwan 713104, West Bengal, India.

Nanoparticles of NiZnCaFeO (NZCF) were successfully prepared by the facile wet chemical method coupled with the sonochemical method. These nanoparticles were embedded in a graphene oxide (GO) matrix (NZCFG). Rietveld analyses of X-ray diffraction, transmission electron microscope, scanning electron microscope, and X-ray photoelectron spectroscopy were carried out to extract different relevant information regarding the structure, morphology, and ionic state. Read More

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September 2021

Novel chitosan and bacterial cellulose biocomposites tailored with polymeric nanoparticles for modern wound dressing development.

Drug Deliv 2021 Dec;28(1):1932-1950

Department of Biochemistry and Molecular Biology, University of Bucharest, Bucharest, Romania.

Dressing biomaterials play a key role in wound management keeping a moisture medium and protecting against external factors. Natural and synthetic materials could be used as dressings where chitosan and bacterial cellulose is one of the most important solutions. These biopolymers have been used for wound dressing based on their non-toxic, biodegradable, and biocompatible features. Read More

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December 2021

Particle characterisation and bioaccessibility of manganese in particulate matter in silico- and ferromanganese smelters.

Environ Sci Process Impacts 2021 Sep 22. Epub 2021 Sep 22.

National Institute of Occupational Health, Gydas vei 8, N-0363 Oslo, Norway.

The aim of this study was to characterise particulate matter (PM) collected in the furnace area during SiMn and high carbon (HC)-FeMn production in terms of single particle analysis and to determine the bioaccessibility of Mn in the PM in a simulated lung fluid. Airborne PM was collected with Sioutas cascade impactors and respirable cyclones in the breathing zone of tappers and crane operators. Stationary samples were collected from the furnace area with a nanoMOUDI cascade impactor and an ESPnano electrostatic particle collector. Read More

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September 2021

Syntheses of -Type Zeolites with the Presence of Both Octyltrimethylammonium Chloride and -Type Zeolite Seeds.

ACS Omega 2021 Sep 2;6(36):23598-23606. Epub 2021 Sep 2.

School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, PR China.

Structure-directing agents (SDAs) play important roles in directing the formation of specific zeolite frameworks. Mechanisms and working hypothesis were proposed for understanding how SDAs work during the crystallization of zeolites. The lately reported cooperative structure-directing effect based on the investigation into the synthetic system containing both seed and organic species is one of them and is believed to be effective for synthesizing zeolites which are difficult to access or with novel structures. Read More

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September 2021

Cleavage of Calcitic CaCO during Dissolution in Aqueous Solution.

ACS Omega 2021 Sep 31;6(36):23311-23316. Epub 2021 Aug 31.

Deptartment of Materials Science and Engineering, Jungwon University, 85 Munmu-ro, Goesan, Chungbuk 28024, Republic of Korea.

Calcite cleavage was observed using a device to accelerate the formation and dissolution of calcitic CaCO by acidification in aqueous solutions. Scanning electron microscopy showed that crystals formed within 1 day and dissolution began at 3 days of aging. In the X-ray diffraction pattern, calcite was predominantly formed but an amorphous phase did not exist, even after 12 days of aging. Read More

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September 2021

One-step preparation of bioactive enzyme/inorganic materials.

J Mater Chem B 2021 Sep 21. Epub 2021 Sep 21.

Department of Chemistry, University of Connecticut, U3060, Storrs, CT, 06269, USA.

Simultaneous exfoliation of crystalline α-zirconium phosphate (α-ZrP) nanosheets and enzyme binding, induced by shearing, without the addition of any toxic additives is reported here for the first time. These materials were thoroughly characterized and used for applications. The bulk α-ZrP material (20 mg mL) was exfoliated with low concentrations of a protein such as bovine serum albumin (BSA, 3 mg mL) in a shear reactor at 10k rpm for <80 minutes. Read More

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September 2021

Ultrastructural aspects of the skin in lipoid proteinosis (Urbach-Wiethe disease).

An Bras Dermatol 2021 Sep 17. Epub 2021 Sep 17.

Department of Dermatology, Universidade Federal da São Paulo, São Paulo, SP, Brazil.

Lipoid proteinosis is a rare autosomal recessive disease, characterized by hyaline deposits of PAS-positive material in tissues due to mutations in the ECM1 gene. This study evaluated the ultrastructure of the skin of a 6-year-old child affected by this condition. The light microscopy identified PAS-positive hyaline deposits, which were more intense in the papillary dermis. Read More

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September 2021

Synthesis of Capsaicin Loaded Silver Nanoparticles Using Green Approach and Its Anti-Bacterial Activity Against Human Pathogens.

J Biomed Nanotechnol 2021 Aug;17(8):1612-1626

Department of Basic Sciences, Common First Year Deanship, Umm Al-Qura University, Makkah, 24230, Saudi Arabia.

Nanotechnology is drawing attention nowadays due to its ability to regulate metals into nanosize, ultimately changing metal's physical, chemical, and optical properties. Silver nanoparticles are known for their potential impact as antimicrobial agents due to their inherent property penetrating the cell wall. The present study aimed to develop and statistically optimise using a novel combination of capsaicin loaded silver nanoparticles (AgCNPs) as an effective anti-bacterial agent to treat psoriasis using a green approach. Read More

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Segmentation of Static and Dynamic Atomic-Resolution Microscopy Data Sets with Unsupervised Machine Learning Using Local Symmetry Descriptors.

Microsc Microanal 2021 Sep 21:1-11. Epub 2021 Sep 21.

Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Straße 1, 40237Düsseldorf, Germany.

We present an unsupervised machine learning approach for segmentation of static and dynamic atomic-resolution microscopy data sets in the form of images and video sequences. In our approach, we first extract local features via symmetry operations. Subsequent dimension reduction and clustering analysis are performed in feature space to assign pattern labels to each pixel. Read More

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September 2021

Coaxially electrospun 5-fluorouracil-loaded PLGA / PVP fibrous membrane for skin tumor treatment.

Biomed Mater 2021 Sep 20. Epub 2021 Sep 20.

Beijing University of Chemical Technology, Beisanhuan East Road, Chaoyang District, Beijing, 100029, CHINA.

As a biocompatible and biodegradable polymer, poly(lactide-co-glycolide) (PLGA) has been widely used as a carrier to achieve controlled drug delivery in various forms. Focusing on skin tumor treatment, herein 5-fluorouracil (5-FU) was embedded into the core of coaxially electrospun PLGA fibers to get a drug-loaded core-shell fibrous membrane. In the coaxial electrospinning, poly(vinylpyrrolidone) (PVP) was applied in the inner flow to facilitate the formation of the core-shell structured fibers. Read More

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September 2021

Synthesis of β-Glucan Nanoparticles from Red Algae-Derived β-Glucan for Potential Biomedical Applications.

Appl Biochem Biotechnol 2021 Sep 20. Epub 2021 Sep 20.

Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India.

The present study highlights/demonstrates facile synthesis of β-Glucan nanoparticles (β-GluNPs) that can be used in the prevention of breast cancer and other infectious diseases. Moreover, this method is inexpensive and shows effectivity towards different biological applications. Further, the characterization of synthesized β-GluNPs was exclusively confirmed through UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), zeta potential, scanning electron microscopy (SEM), high resolution-transmission electron microscopy (HR-TEM), and X-ray powder diffraction (XRD) analysis. Read More

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September 2021

A solution scan of societal options to reduce transmission and spread of respiratory viruses: SARS-CoV-2 as a case study.

J Biosaf Biosecur 2021 Sep 15. Epub 2021 Sep 15.

Department of Zoology, University of Cambridge, The David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK.

Societal biosecurity, measures built into everyday society to minimize risks from pests and diseases, is an important aspect of managing epidemics and pandemics. We aimed to identify societal options for reducing the transmission and spread of respiratory viruses. We used SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) as a case study to meet the immediate need to manage the COVID-19 pandemic and eventually transition to more normal societal conditions, and to catalog options for managing similar pandemics in the future. Read More

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September 2021

Green Synthesis of New Category of Pyrano[3,2-c]Chromene-Diones Catalyzed by Nanocomposite as [email protected] Covalented Dapsone-Copper Complex.

Authors:
Leila Zare Fekri

Front Chem 2021 1;9:720555. Epub 2021 Sep 1.

Department of Chemistry, Payame Noor University, Tehran, Iran.

Nanomagnetic dapsone-Cu supported on the silica-coated FeO ([email protected]@dapsone-Cu) nanocomposite was synthesized and characterized by Fourier transform infrared (FT-IR), energy-dispersive X-ray (EDX), X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), zeta potential, vibrating sample magnetometer (VSM), and thermogravimetric analysis (TGA). This newly synthesized nanocomposite was chosen to act as a green, efficient, and recyclable Lewis acid for the multicomponent synthesis of new derivatives of pyrano[3,2-c]chromene-diones through the reaction of aromatic aldehydes, indandione, and 4-hydroxycoumarin in water. All of the synthesized compounds are new and are recognized by FT-IR, NMR, and elemental analysis; this avenue is new and has advantages such as short reaction times, high productivity, economical synthesis, and use of green solvent, HO, as a medium. Read More

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September 2021

Stability and remineralization of proteoglycan-infused dentin substrate.

Dent Mater 2021 Sep 15. Epub 2021 Sep 15.

Division of Comprehensive Oral Health, Adams School of Dentistry, The University of North Carolina at Chapel Hill, NC, USA. Electronic address:

Objective: This study tested the effects of small leucine-rich proteoglycan (SLRP) proteins on phosphoric acid (PA)-treated dentin bonding overtime and the role of such SLRPs in the remineralization potential of demineralized dentin collagen.

Methods: Coronal dentin sections of human molars were used. SLRPs were either decorin (DCN) or biglycan (BGN) in core or proteoglycan form (with glycosaminoglycans, GAGs). Read More

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September 2021

Pathology of lung-specific thrombosis and inflammation in COVID-19.

J Thromb Haemost 2021 Sep 19. Epub 2021 Sep 19.

Departments of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.

Background: Infection by SARS-CoV-2 produces significant pulmonary pathology including endothelial damage with resultant thrombotic events. While pathologic features were described, there is limited data on the relationship of these changes to the inflammatory response and the production of thromboses.

Objective: To investigate pathology of COVID-19-related immunothrombosis. Read More

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September 2021

Synthesis and characterization of ZnGaO composites and its photocatalytic properties for energy applications.

Environ Res 2021 Sep 16;204(Pt B):112073. Epub 2021 Sep 16.

PG & Research Department of Chemistry, KhadirMohideen College, Adirampattinam, (Affiliated to Bharathidasan University, Thiruchirappalli, 614701, India; PG & Research Department of Physics, KhadirMohideen College, Adirampattinam, (Affiliated to Bharathidasan University, Thiruchirappalli, 614701, India. Electronic address:

ZnGaO nanocomposites have been widely used for photocatalytic degradation of industrial dyes. In this work, ZnGaO was synthesized from zinc sulphate heptahydrate ZnSO10HO and Gallium (III) oxide (GaO) by hydrothermal method. As prepared, ZnGaO nanocomposites was used as a photocatalyst degradation of three organic dyes rhodamine-B, methylene blue, and methyl orange, under ultraviolet (UV) light irradiation. Read More

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September 2021

Preparation of magnetic yolk-shell structured metal-organic framework material and its application in pharmacokinetics study of alkaloids.

Anal Bioanal Chem 2021 Sep 17. Epub 2021 Sep 17.

School of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 401331, People's Republic of China.

In this study, a magnetic yolk-shell structured metal-organic framework material ([email protected]) is prepared by the directional etching of Co/peroxymonosulfate and in situ magnetization. The characteristic properties of the material were investigated by using field emission scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, vibrating sample magnetometer, Brunauer-Emmett-Teller, and contact angle test. The [email protected] shows the advantages of large surface area, good magnetic property, and satisfactory stability, as well as giving high affinity to alkaloids (ALs) via hydrophilic interaction, hydrogen bonding, and π-π interaction. Read More

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September 2021