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Innovative hydrolysis of corn stover biowaste by modified magnetite laccase immobilized nanoparticles

Gou Z, Ma NL, Zhang W, Lei Z, Su Y, Sun C, et al.

Environ Res, 2020 09;188:109829.
PMID: 32798948 DOI: 10.1016/j.envres.2020.109829

Intensive studies have been performed on the improvement of bioethanol production by transformation of lignocellulose biomass. In this study, the digestibility of corn stover was dramatically improved by using laccase immobilized on Cu2+ modified recyclable magnetite nanoparticles, Fe3O4-NH2. After digestion, the laccase was efficiently separated from slurry. The degradation rate of lignin reached 40.76%, and the subsequent cellulose conversion rate 38.37% for 72 h at 35 °C with cellulase at 50 U g-1 of corn stover. Compared to those of free and inactivated mode, the immobilized laccase pre-treatment increased subsequent cellulose conversion rates by 23.98% and 23.34%, respectively. Moreover, the reusability of immobilized laccase activity remained 50% after 6 cycles. The storage and thermal stability of the fixed laccase enhanced by 70% and 24.1% compared to those of free laccase at 65 °C, pH 4.5, respectively. At pH 10.5, it exhibited 16.3% more activities than its free mode at 35 °C. Our study provides a new avenue for improving the production of bioethanol with immobilized laccase for delignification using corn stover as the starting material.

Matched MeSH terms: Magnetite Nanoparticles*
Low-gradient magnetic separation of magnetic nanoparticles under continuous flow: Experimental study, transport mechanism and mathematical modelling

Tan YW, Leong SS, Lim J, Yeoh WM, Toh PY

Electrophoresis, 2022 Nov;43(21-22):2234-2249.
PMID: 35921231 DOI: 10.1002/elps.202200078

Low-gradient magnetic separation (LGMS) of magnetic nanoparticles (MNPs) has been proven as one of the techniques with great potential for biomedical and environmental applications. Recently, the underlying principle of particle capture by LGMS, through a process known as magnetophoresis, under the influence of hydrodynamic effect has been widely studied and illustrated. Even though the hydrodynamic effect is very substantial for batch processes, its impact on LGMS operated at continuous flow (CF) condition remained largely unknown. Hence, in this study, the dynamical behaviour of LGMS process operated under CF was being studied. First, the LGMS experiments using poly(sodium 4-styrenesulfonate)-functionalized-MNP as modelled particle system were performed through batchwise (BW) and CF modes at different operating conditions. Here BW operation was used as a comparative study to elucidate the transport mechanism of MNP under the similar environment of CF-LGMS process, and it was found out that the convection induced by magnetophoresis (timescale effective is ∼1200 s) is only significant at far-from-magnet region. Hence, it can be deduced that forced convection is more dominant on influencing the transport behaviour of CF-LGMS (with resident time ≤240 s). Moreover, we found that the separation efficiency of CF-LGMS process can be boosted by the higher number of magnets, the higher MNP concentration and the lower flowrate of MNP solution. To better illustrate the underlying dynamical behaviour of LGMS process, a mathematical model was developed to predict its kinetic profile and separation efficiency (with average error of ∼2.6% compared to the experimental results).

Matched MeSH terms: Magnetite Nanoparticles*
A Perspective on Therapeutic Applications and Strategies to Mitigate Toxicity of Metallic Nanoparticles

Karuppaiah A, Selvaraj D, Sellappan M, Nagarajan A, Babu D, Rahman H, et al.

Curr Pharm Des, 2023;29(4):239-245.
PMID: 36624648 DOI: 10.2174/1381612829666230109111635

Metallic nanoparticles (MNPs) have been widely used for diagnostic and therapeutic purposes in clinical practice. A number of MNP formulations are being investigated in clinical trials for various applications. This increase in the use of NPs results in higher exposure to humans, leading to toxicity issues. Hence, it is necessary to determine the possible undesirable effects of the MNPs after in-vivo application and exposure. One of the main reasons for the toxicity of MNPs is the release of their respective metallic ions throughout the body. Many research studies are in progress investigating the various strategies to reduce the toxicity of MNPs. These research studies aim to change the size, dose, agglomeration, release, and excretion rates of MNPs. In this perspective review, we discussed the possible strategies to improve the therapeutic effects of MNPs through various processes, with lessons learned from the studies involving silver nanoparticles (AgNPs). We also discussed the ways to manage the toxicity of MNPs by purification, surface functionalization, synergistic effect, and targeted therapy approach. All these strategies could reduce the dose of the MNPs without compromising their therapeutic benefits, which could decrease the toxicity of MNPs. Additionally, we briefly discussed the market and toxicology testing for FDA-regulated MNPs.

Matched MeSH terms: Magnetite Nanoparticles*
Fulltext Radiolytic formation of Fe3O4 nanoparticles: influence of radiation dose on structure and magnetic properties

Abedini A, Daud AR, Abdul Hamid MA, Kamil Othman N

PLoS One, 2014;9(3):e90055.
PMID: 24608715 DOI: 10.1371/journal.pone.0090055

Colloidal Fe3O4 nanoparticles were synthesized using a gamma-radiolysis method in an aqueous solution containing iron chloride in presence of polyvinyl alcohol and isopropanol as colloidal stabilizer and hydroxyl radical scavenger, respectively. Gamma irradiation was carried out in a 60Co gamma source chamber at different absorbed doses. Increasing the radiation dose above a certain critical dose (100 kGy) leads to particle agglomeration enhancement, and this can influence the structure and crystallinity, and consequently the magnetic properties of the resultant particles. The optimal condition for formation of Fe3O4 nanoparticles with a uniform and narrow size distribution occurred at a dose of 100 kGy, as confirmed by X-ray diffractometry and transmission electron microscopy. A vibrating sample magnetometry study showed that, when radiation dose increased, the saturation and remanence magnetization decreased, whereas the coercivity and the remanence ratio increased. This magnetic behavior results from variations in crystallinity, surface effects, and particle size effects, which are all dependent on the radiation dose. In addition, Fourier transform infrared spectroscopy was performed to investigate the nature of the bonds formed between the polymer chains and the metal surface at different radiation doses.

Matched MeSH terms: Magnetite Nanoparticles/radiation effects; Magnetite Nanoparticles/ultrastructure; Magnetite Nanoparticles/chemistry*
Magnetic Nanoparticle-Based Semi-automated Panning for High-Throughput Antibody Selection

Ch'ng ACW, Konthur Z, Lim TS

Methods Mol Biol, 2023;2702:291-313.
PMID: 37679626 DOI: 10.1007/978-1-0716-3381-6_15

Bio-panning is a common process involved in recombinant antibody selection against defined targets. The biopanning process aims to isolate specific antibodies against an antigen via affinity selection from a phage display library. In general, antigens are immobilized on solid surfaces such as polystyrene plastic, magnetic beads, and nitrocellulose. For high-throughput selection, semi-automated panning selection allows simultaneous panning against multiple target antigens adapting automated particle processing systems such as the KingFisher Flex. The system setup allows for minimal human intervention for pre- and post-panning steps such as antigen immobilization, phage rescue, and amplification. In addition, the platform is also adaptable to perform polyclonal and monoclonal ELISA for the evaluation process. This chapter will detail the protocols involved from the selection stage until the monoclonal ELISA evaluation with important notes attached at the end of this chapter for optimization and troubleshooting purposes.

Matched MeSH terms: Magnetite Nanoparticles*
Fulltext Ultrasmall superparamagnetic Fe3O4 nanoparticles: honey-based green and facile synthesis and in vitro viability assay

Rasouli E, Basirun WJ, Rezayi M, Shameli K, Nourmohammadi E, Khandanlou R, et al.

Int J Nanomedicine, 2018;13:6903-6911.
PMID: 30498350 DOI: 10.2147/IJN.S158083

Introduction: In the present research, we report a quick and green synthesis of magnetite nanoparticles (Fe3O4-NPs) in aqueous solution using ferric and ferrous chloride, with different percentages of natural honey (0.5%, 1.0%, 3.0% and 5.0% w/v) as the precursors, stabilizer, reducing and capping agent, respectively. The effect of the stabilizer on the magnetic properties and size of Fe3O4-NPs was also studied.
Methods: The nanoparticles were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy, energy dispersive X-ray fluorescence, transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy.
Results: The XRD analysis indicated the presence of pure Fe3O4-NPs while the TEM images indicated that the Fe3O4-NPs are spherical with a diameter range between 3.21 and 2.22 nm. The VSM study demonstrated that the magnetic properties were enhanced with the decrease in the percentage of honey. In vitro viability evaluation of Fe3O4-NPs performed by using the MTT assay on the WEHI164 cells demonstrated no significant toxicity in higher concentration up to 140.0 ppm, which allows them to be used in some biological applications such as drug delivery.
Conclusion: The presented synthesis method can be used for the controlled synthesis of Fe3O4-NPs, which could be found to be important in applications in biotechnology, biosensor and biomedicine, magnetic resonance imaging and catalysis.

Matched MeSH terms: Magnetite Nanoparticles/administration & dosage*; Magnetite Nanoparticles/chemistry*
Fulltext The ability of streptomycin-loaded chitosan-coated magnetic nanocomposites to possess antimicrobial and antituberculosis activities

El Zowalaty ME, Hussein Al Ali SH, Husseiny MI, Geilich BM, Webster TJ, Hussein MZ

Int J Nanomedicine, 2015;10:3269-74.
PMID: 25995633 DOI: 10.2147/IJN.S74469

Magnetic nanoparticles (MNPs) were synthesized by the coprecipitation of Fe(2+) and Fe(3+) iron salts in alkali media. MNPs were coated by chitosan (CS) to produce CS-MNPs. Streptomycin (Strep) was loaded onto the surface of CS-MNPs to form a Strep-CS-MNP nanocomposite. MNPs, CS-MNPs, and the nanocomposites were subsequently characterized using X-ray diffraction and were evaluated for their antibacterial activity. The antimicrobial activity of the as-synthesized nanoparticles was evaluated using different Gram-positive and Gram-negative bacteria, as well as Mycobacterium tuberculosis. For the first time, it was found that the nanoparticles showed antimicrobial activities against the tested microorganisms (albeit with a more pronounced effect against Gram-negative than Gram-positive bacteria), and thus, should be further studied as a novel nano-antibiotic for numerous antimicrobial and antituberculosis applications. Moreover, since these nanoparticle bacteria fighters are magnetic, one can easily envision magnetic field direction of these nanoparticles to fight unwanted microorganism presence on demand. Due to the ability of magnetic nanoparticles to increase the sensitivity of imaging modalities (such as magnetic resonance imaging), these novel nanoparticles can also be used to diagnose the presence of such microorganisms. In summary, although requiring further investigation, this study introduces for the first time a new type of magnetic nanoparticle with microorganism theranostic properties as a potential tool to both diagnose and treat diverse microbial and tuberculosis infections.

Matched MeSH terms: Magnetite Nanoparticles/chemistry*
Fulltext Chlorambucil-Iron Oxide Nanoparticles as a Drug Delivery System for Leukemia Cancer Cells

Hussein-Al-Ali SH, Hussein MZ, Bullo S, Arulselvan P

Int J Nanomedicine, 2021;16:6205-6216.
PMID: 34526768 DOI: 10.2147/IJN.S312752

Introduction: Traditional cancer therapies may have incomplete eradication of cancer or destroy the normal cells. Nanotechnology solves the demerit by a guide in surgical resection of tumors, targeted chemotherapies, selective to cancerous cells, etc. This new technology can reduce the risk to the patient and automatically increased the probability of survival. Toward this goal, novel iron oxide nanoparticles (IONPs) coupled with leukemia anti-cancer drug were prepared and assessed.
Methods: The IONPs were prepared by the co-precipitation method using Fe+3/Fe+2ratio of 2:1. These IONPs were used as a carrier for chlorambucil (Chloramb), where the IONPs serve as the cores and chitosan (CS) as a polymeric shell to form Chloramb-CS-IONPs. The products were characterized using transmission electron microscopy (TEM), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) analysis, Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometry (VSM) analyses, and thermal gravimetric analysis (TGA).
Results: The as-prepared IONPs were found to be magnetite (Fe3O4) and were coated by the CS polymer/Chloramb drug for the formation of the Chloramb-CS-IONPs. The average size for CS-IONPs and Chloramb-CS-IONPs nanocomposite was found to be 15 nm, with a drug loading of 19% for the letter. The release of the drug from the nanocomposite was found to be of a controlled-release manner with around 89.9% of the drug was released within about 5000 min and governed by the pseudo-second order. The in vitro cytotoxicity studies of CS-IONPs and Chloramb-CS-IONPs nanocomposite were tested on the normal fibroblast cell lines (3T3) and leukemia cancer cell lines (WEHI). Chloramb in Chloramb-CS-IONPs nanocomposite was found to be more efficient compared to its free form.
Conclusion: This work shows that Chloramb-CS-IONPs nanocomposite is a promising candidate for magnetically targeted drug delivery for leukemia anti-cancer agents.

Matched MeSH terms: Magnetite Nanoparticles*
Simultaneous removal of potent cyanotoxins from water using magnetophoretic nanoparticle of polypyrrole: adsorption kinetic and isotherm study

Hena S, Rozi R, Tabassum S, Huda A

Environ Sci Pollut Res Int, 2016 Aug;23(15):14868-80.
PMID: 27072032 DOI: 10.1007/s11356-016-6540-5

Cyanotoxins, microcystins and cylindrospermopsin, are potent toxins produced by cyanobacteria in potable water supplies. This study investigated the removal of cyanotoxins from aqueous media by magnetophoretic nanoparticle of polypyrrole adsorbent. The adsorption process was pH dependent with maximum adsorption occurring at pH 7 for microcystin-LA, LR, and YR and at pH 9 for microcystin-RR and cylindrospermopsin (CYN). Kinetic studies and adsorption isotherms reflected better fit for pseudo-second-order rate and Langmuir isotherm model, respectively. Thermodynamic calculations showed that the cyanotoxin adsorption process is endothermic and spontaneous in nature. The regenerated adsorbent can be successfully reused without appreciable loss of its original capacity.

Matched MeSH terms: Magnetite Nanoparticles/chemistry*
Fulltext Characterization of magnetic nanoparticle by dynamic light scattering

Lim J, Yeap SP, Che HX, Low SC

Nanoscale Res Lett, 2013;8(1):381.
PMID: 24011350 DOI: 10.1186/1556-276X-8-381

Here we provide a complete review on the use of dynamic light scattering (DLS) to study the size distribution and colloidal stability of magnetic nanoparticles (MNPs). The mathematical analysis involved in obtaining size information from the correlation function and the calculation of Z-average are introduced. Contributions from various variables, such as surface coating, size differences, and concentration of particles, are elaborated within the context of measurement data. Comparison with other sizing techniques, such as transmission electron microscopy and dark-field microscopy, revealed both the advantages and disadvantages of DLS in measuring the size of magnetic nanoparticles. The self-assembly process of MNP with anisotropic structure can also be monitored effectively by DLS.

Matched MeSH terms: Magnetite Nanoparticles
Fulltext Surface-Functionalized Superparamagnetic Nanoparticles (SPNs) for Enhanced Oil Recovery: Effects of Surface Modifiers and Their Architectures

Khalil M, Aulia G, Budianto E, Mohamed Jan B, Habib SH, Amir Z, et al.

ACS Omega, 2019 Dec 17;4(25):21477-21486.
PMID: 31867543 DOI: 10.1021/acsomega.9b03174

Superparamagnetic nanoparticles (SPNs) have been considered as one of the most studied nanomaterials for subsurface applications, including in enhanced oil recovery (EOR), due to their unique physicochemical properties. However, a comprehensive understanding of the effect of surface functionalization on the ability of the nanoparticles to improve secondary and tertiary oil recoveries remains unclear. Therefore, investigations on the application of bare and surface-functionalized SPNs in EOR using a sand pack were carried out in this study. Here, the as-prepared SPNs were functionalized using oleic acid (OA) and polyacrylamide (PAM) to obtain several types of nanostructure architectures such as OA-SPN, core-shell SPN@PAM, and SPN-PAM. Based on the result, it is found that both the viscosity and mobility of the nanofluids were significantly affected by not only the concentration of the nanoparticles but also the type and architecture of the surface modifier, which dictated particle hydrophilicity. According to the sand pack tests, the nanofluid containing SPN-PAM was able to recover as much as 19.28% of additional oil in a relatively low concentration (0.9% w/v). The high oil recovery enhancement was presumably due to the ability of suspended SPN-PAM to act as a mobility control and wettability alteration agent and facilitate the formation of a Pickering emulsion and disjoining pressure.

Matched MeSH terms: Magnetite Nanoparticles
Electrosteric stabilization and its role in cooperative magnetophoresis of colloidal magnetic nanoparticles

Yeap SP, Ahmad AL, Ooi BS, Lim J

Langmuir, 2012 Oct 23;28(42):14878-91.
PMID: 23025323 DOI: 10.1021/la303169g

A detailed study on the conflicting role that colloid stability plays in magnetophoresis is presented. Magnetic iron oxide particles (MIOPs) that were sterically stabilized via surface modification with poly(sodium 4-styrene sulfonate) of different molecular weights (i.e., 70 and 1000 kDa) were employed as our model system. Both sedimentation kinetics and quartz crystal microbalance with dissipation (QCM-D) measurements suggested that PSS 70 kDa is a better stabilizer as compared to PSS 1000 kDa. This observation is mostly attributed to the bridging flocculation of PSS 1000 kDa decorated MIOPs originated from the extended polymeric conformation layer. Later, a lab-scale high gradient magnetic separation (HGMS) device was designed to study the magnetophoretic collection of MIOPs. Our experimental results revealed that the more colloidally stable the MIOP suspension is, the harder it is to be magnetically isolated by HGMS. At 50 mg/L, naked MIOPs without coating can be easily captured by HGMS at separation efficiency up to 96.9 ± 2.6%. However, the degree of separation dropped quite drastically to 83.1 ± 1.2% and 67.7 ± 4.6%, for MIOPs with PSS 1000k and PSS 70k coating, respectively. This observation clearly implies that polyelectrolyte coating that was usually employed to electrosterically stabilize a colloidal system in turn compromises the magnetic isolation efficiency. By artificially destroying the colloidal stability of the MIOPs with ionic strength increment, the ability for HGMS to recover the most stable suspension (i.e., PSS 70k-coated MIOPs) increased to >86% at 100 mM monovalent ion (Na(+)) or at 10 mM divalent ion (Ca(2+)). This observation has verified the conflicting role of colloidal stability in magnetophoretic separation.

Matched MeSH terms: Magnetite Nanoparticles/chemistry*
Magnetic solid-phase extraction based on modified ferum oxides for enrichment, preconcentration, and isolation of pesticides and selected pollutants

Wan Ibrahim WA, Nodeh HR, Aboul-Enein HY, Sanagi MM

Crit Rev Anal Chem, 2015;45(3):270-87.
PMID: 25849825 DOI: 10.1080/10408347.2014.938148

Recently, a simple, rapid, high-efficiency, selective, and sensitive method for isolation, preconcentration, and enrichment of analytes has been developed. This new method of sample handling is based on ferum oxides as magnetic nanoparticles (MNPs) and has been used for magnetic solid-phase extraction (MSPE) of various analytes from various matrices. This review focuses on the applications of modified ferum oxides, especially modified Fe3O4 MNPs, as MSPE adsorbent for pesticide isolation from various matrices. Further perspectives on MSPE based on modified Fe3O4 for inorganic metal ions, organic compounds, and biological species from water samples are also presented. Ferum(III) oxide MNPs (Fe2O3) are also highlighted.

Matched MeSH terms: Magnetite Nanoparticles/chemistry*
A High-Throughput Magnetic Nanoparticle-Based Semi-Automated Antibody Phage Display Biopanning

Ch'ng ACW, Ahmad A, Konthur Z, Lim TS

Methods Mol Biol, 2019;1904:377-400.
PMID: 30539481 DOI: 10.1007/978-1-4939-8958-4_18

Panning is a common process used for antibody selection from phage antibody libraries. There are several methods developed for a similar purpose, namely streptavidin mass spectrometry immunoassay (MSIA™) Disposable Automation Research Tips, magnetic beads, polystyrene immunotubes, and microtiter plate. The advantage of using a magnetic particle processor system is the ability to carry out phage display panning against multiple target antigens simultaneously in parallel. The system carries out the panning procedure using magnetic nanoparticles in microtiter plates. The entire incubation, wash, and elution process is then automated in this setup. The system also allows customization for the introduction of different panning stringencies. The nature of the biopanning process coupled with the limitation of the system means that minimal human intervention is required for the infection and phage packaging stage. However, the process still allows for rapid and reproducible antibody generation to be carried out.

Matched MeSH terms: Magnetite Nanoparticles*
Polyethylene glycol-coated porous magnetic nanoparticles for targeted delivery of chemotherapeutics under magnetic hyperthermia condition

Dabbagh A, Hedayatnasab Z, Karimian H, Sarraf M, Yeong CH, Madaah Hosseini HR, et al.

Int J Hyperthermia, 2019;36(1):104-114.
PMID: 30428737 DOI: 10.1080/02656736.2018.1536809

PURPOSE: Although magnetite nanoparticles (MNPs) are promising agents for hyperthermia therapy, insufficient drug encapsulation efficacies inhibit their application as nanocarriers in the targeted drug delivery systems. In this study, porous magnetite nanoparticles (PMNPs) were synthesized and coated with a thermosensitive polymeric shell to obtain a synergistic effect of hyperthermia and chemotherapy.
MATERIALS AND METHODS: PMNPs were produced using cetyltrimethyl ammonium bromide template and then coated by a polyethylene glycol layer with molecular weight of 1500 Da (PEG1500) and phase transition temperature of 48 ± 2 °C to endow a thermosensitive behavior. The profile of drug release from the nanostructure was studied at various hyperthermia conditions generated by waterbath, magnetic resonance-guided focused ultrasound (MRgFUS), and alternating magnetic field (AMF). The in vitro cytotoxicity and hyperthermia efficacy of the doxorubicin-loaded nanoparticles (DOX-PEG1500-PMNPs) were assessed using human lung adenocarcinoma (A549) cells.
RESULTS: Heat treatment of DOX-PEG1500-PMNPs containing 235 ± 26 mg·g-1 DOX at 48 °C by waterbath, MRgFUS, and AMF, respectively led to 71 ± 4%, 48 ± 3%, and 74 ± 5% drug release. Hyperthermia treatment of the A549 cells using DOX-PEG1500-PMNPs led to 77% decrease in the cell viability due to the synergistic effects of magnetic hyperthermia and chemotherapy.
CONCLUSION: The large pores generated in the PMNPs structure could provide a sufficient space for encapsulation of the chemotherapeutics as well as fast drug encapsulation and release kinetics, which together with thermosensitive characteristics of the PEG1500 shell, make DOX-PEG1500-PMNPs promising adjuvants to the magnetic hyperthermia modality.

Matched MeSH terms: Magnetite Nanoparticles/chemistry*
Magnetic nanoparticles incorporation into different substrates for dyes and heavy metals removal-A Review

Khan FSA, Mubarak NM, Tan YH, Karri RR, Khalid M, Walvekar R, et al.

Environ Sci Pollut Res Int, 2020 Dec;27(35):43526-43541.
PMID: 32909134 DOI: 10.1007/s11356-020-10482-z

Substantial discharge of hazardous substances, especially dyes and heavy metal ions to the environment, has become a global concern due to many industries neglecting the environmental protocols in waste management. A massive discharge of contaminantsfrom different anthropogenic activities, can pose alarming threats to living species and adverse effect to the ecosystem stability. In the process of treating the polluted water, various methods and materials are used. Hybrid nanocomposites have attained numerous interest due to the combination of remarkable features of the organic and inorganic elements in a single material. In this regards, carbon and polymer based nanocomposites have gained particular interest because of their tremendous magnetic properties and stability. These nanocomposites can be fabricated using several approaches that include filling, template, hydrothermal, pulsed-laser irradiation, electro-spinning, detonation induced reaction, pyrolysis, ball milling, melt-blending, and many more. Moreover, carbon-based and polymer-based magnetic nanocomposites have been utilized for an extensive number of applications such as removal of heavy metal and dye adsorbents, magnetic resonance imaging, and drug delivery. This review emphasized mainly on the production of magnetic carbon and polymer nanocomposites employing various approaches and their applications in water and wastewater treatment. Furthermore, the future opportunities and challenges in applying magnetic nanocomposites for heavy metal ion and dye removal from water and wastewater treatment plant.

Matched MeSH terms: Magnetite Nanoparticles*
Uptake and clearance analysis of Technetium99m labelled iron oxide nanoparticles in a rabbit brain

Nadeem M, Ahmad M, Saeed MA, Shaari A, Riaz S, Naseem S, et al.

IET Nanobiotechnol, 2015 Jun;9(3):136-41.
PMID: 26023157 DOI: 10.1049/iet-nbt.2014.0012

Nanoparticles as solid colloidal particles are extensively studied and used as anticancer drug delivery agents because of their physical properties. This current research aims to prepare water base suspension of uncoated iron oxide nanoparticles and their biodistribution study to different organs, especially the brain, by using a single photon emission computed tomography gamma camera. The water-based suspension of iron oxide nanoparticles was synthesised by a reformed version of the co-precipitation method and labelled with Tc99m for intravenous injection. The nanoparticles were injected without surface modification. X-ray diffraction (XRD), energy dispersive spectrometry (EDS) and transmission electron microscope (TEM) techniques were used for characterisation. Peaks of XRD and EDS indicate that the particles are magnetite and exist in aqueous suspension. The average diameter of iron oxide nanoparticles without any surface coating determined by TEM is 10 nm. These particles are capable of evading the reticuloendothelial system and can cross the blood-brain barrier in the rabbit. The labelling efficiency of iron oxide nanoparticles labelled with Tc99m is 85%, which is good for the biodistribution study. The sufficient amount of iron oxide nanoparticles concentration in the brain as compared with the surrounding soft tissues and their long blood retention time indicates that the water-based suspension of iron oxide nanoparticles may be an option for drug delivery into the brain.

Matched MeSH terms: Magnetite Nanoparticles/chemistry*
Unified View of Magnetic Nanoparticle Separation under Magnetophoresis

Leong SS, Ahmad Z, Low SC, Camacho J, Faraudo J, Lim J

Langmuir, 2020 07 21;36(28):8033-8055.
PMID: 32551702 DOI: 10.1021/acs.langmuir.0c00839

The migration process of magnetic nanoparticles and colloids in solution under the influence of magnetic field gradients, which is also known as magnetophoresis, is an essential step in the separation technology used in various biomedical and engineering applications. Many works have demonstrated that in specific situations, separation can be performed easily with the weak magnetic field gradients created by permanent magnets, a process known as low-gradient magnetic separation (LGMS). Due to the level of complexity involved, it is not possible to understand the observed kinetics of LGMS within the classical view of magnetophoresis. Our experimental and theoretical investigations in the last years unravelled the existence of two novel physical effects that speed up the magnetophoresis kinetics and explain the observed feasibility of LGMS. Those two effects are (i) cooperative magnetophoresis (due to the cooperative motion of strongly interacting particles) and (ii) magnetophoresis-induced convection (fluid dynamics instability originating from inhomogeneous magnetic gradients). In this feature article, we present a unified view of magnetophoresis based on the extensive research done on these effects. We present the physical basis of each effect and also propose a classification of magnetophoresis into four distinct regimes. This classification is based on the range of values of two dimensionless quantities, namely, aggregation parameter N* and magnetic Grashof number Grm, which include all of the dependency of LGMS on various physical parameters (such as particle properties, thermodynamic parameters, fluid properties, and magnetic field properties). This analysis provides a holistic view of the classification of transport mechanisms in LGMS, which could be particularly useful in the design of magnetic separators for engineering applications.

Matched MeSH terms: Magnetite Nanoparticles
Publication Trends in Drug Delivery and Magnetic Nanoparticles

Ale Ebrahim S, Ashtari A, Zamani Pedram M, Ale Ebrahim N

Nanoscale Res Lett, 2019 May 16;14(1):164.
PMID: 31098855 DOI: 10.1186/s11671-019-2994-y

This bibliometric study investigated the public trends in the fields of nanoparticles which is limited to drug delivery and magnetic nanoparticles' literature published from 1980 to October 2017. The data were collected from the Web of Science Core Collections, and a network analysis of research outputs was carried out to analyse the research trends in the nanoparticles literature. Nanoparticles and its applications are progressing in recent years. The results show that documents in the field of nanoparticles in chemistry and material science have improved in citation rate, as the authors were researching in multidisciplinary zones. Top-cited documents are mainly focusing on drug delivery, magnetic nanoparticles and iron oxide nanoparticles which are also the top research keywords in all papers published. Top-cited papers are mostly published in Biomaterials journal which so far has published 12% of top-cited articles. Although research areas such as contrast agents, quantum dots, and nanocrystals are not considered as the top-ranked keywords in all documents, these keywords received noticeable citations. The trends of publications on drug delivery and magnetic nanoparticles give a general view on future research and identify potential opportunities and challenges.

Matched MeSH terms: Magnetite Nanoparticles
Fulltext Synthesis, surface modification and characterisation of biocompatible magnetic iron oxide nanoparticles for biomedical applications

Mahdavi M, Ahmad MB, Haron MJ, Namvar F, Nadi B, Rahman MZ, et al.

Molecules, 2013 Jun 27;18(7):7533-48.
PMID: 23807578 DOI: 10.3390/molecules18077533

Superparamagnetic iron oxide nanoparticles (MNPs) with appropriate surface chemistry exhibit many interesting properties that can be exploited in a variety of biomedical applications such as magnetic resonance imaging contrast enhancement, tissue repair, hyperthermia, drug delivery and in cell separation. These applications required that the MNPs such as iron oxide Fe₃O₄ magnetic nanoparticles (Fe₃O₄ MNPs) having high magnetization values and particle size smaller than 100 nm. This paper reports the experimental detail for preparation of monodisperse oleic acid (OA)-coated Fe₃O₄ MNPs by chemical co-precipitation method to determine the optimum pH, initial temperature and stirring speed in order to obtain the MNPs with small particle size and size distribution that is needed for biomedical applications. The obtained nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray fluorescence spectrometry (EDXRF), thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), and vibrating sample magnetometer (VSM). The results show that the particle size as well as the magnetization of the MNPs was very much dependent on pH, initial temperature of Fe²⁺ and Fe³⁺ solutions and steering speed. The monodisperse Fe₃O₄ MNPs coated with oleic acid with size of 7.8 ± 1.9 nm were successfully prepared at optimum pH 11, initial temperature of 45°C and at stirring rate of 800 rpm. FTIR and XRD data reveal that the oleic acid molecules were adsorbed on the magnetic nanoparticles by chemisorption. Analyses of TEM show the oleic acid provided the Fe₃O₄ particles with better dispersibility. The synthesized Fe₃O₄ nanoparticles exhibited superparamagnetic behavior and the saturation magnetization of the Fe₃O₄ nanoparticles increased with the particle size.

Matched MeSH terms: Magnetite Nanoparticles/administration & dosage; Magnetite Nanoparticles/chemistry*

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