Magnetic-field-induced orientation of fructose dehydrogenase on iron oxide nanoparticles for enhanced direct electron transfer

2018 ◽  
Vol 93 ◽  
pp. 66-70 ◽  
Author(s):  
Michal Kizling ◽  
Aleksandra Rekorajska ◽  
Pawel Krysinski ◽  
Renata Bilewicz
Keyword(s):  
Magnetic Field ◽  
Electron Transfer ◽  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Direct Electron Transfer ◽  
Oxide Nanoparticles ◽  
Fructose Dehydrogenase

Magnetic targeting with superparamagnetic iron oxide nanoparticles for in vivo glioma

2017 ◽  
Vol 6 (5) ◽  
pp. 449-472 ◽  
Author(s):  
Marina Fontes de Paula Aguiar ◽  
Javier Bustamante Mamani ◽  
Taylla Klei Felix ◽  
Rafael Ferreira dos Reis ◽  
Helio Rodrigues da Silva ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Superparamagnetic Iron Oxide ◽  
Superparamagnetic Iron Oxide Nanoparticles ◽  
Process Efficiency ◽  
Cochrane Library ◽  
Oxide Nanoparticles ◽  
Magnetic Targeting

AbstractThe purpose of this study was to review the use of the magnetic targeting technique, characterized by magnetic driving compounds based on superparamagnetic iron oxide nanoparticles (SPIONs), as drug delivery for a specific brain locus in gliomas. We reviewed a process mediated by the application of an external static magnetic field for targeting SPIONs in gliomas. A search of PubMed, Cochrane Library, Scopus, and Web of Science databases identified 228 studies, 23 of which were selected based on inclusion criteria and predetermined exclusion criteria. The articles were analyzed by physicochemical characteristics of SPIONs used, cell types used for tumor induction, characteristics of experimental glioma models, magnetic targeting technical parameters, and analysis method of process efficiency. The study shows the highlights and importance of magnetic targeting to optimize the magnetic targeting process as a therapeutic strategy for gliomas. Regardless of the intensity of the patterned magnetic field, the time of application of the field, and nanoparticle used (commercial or synthesized), all studies showed a vast advantage in the use of magnetic targeting, either alone or in combination with other techniques, for optimized glioma therapy. Therefore, this review elucidates the preclinical and therapeutic applications of magnetic targeting in glioma, an innovative nanobiotechnological method.

Triggering Mechanism for DNA Electrical Conductivity: Reversible Electron Transfer between DNA and Iron Oxide Nanoparticles

2015 ◽  
Vol 25 (12) ◽  
pp. 1822-1831 ◽  
Author(s):  
Massimiliano Magro ◽  
Davide Baratella ◽  
Petr Jakubec ◽  
Giorgio Zoppellaro ◽  
Jiri Tucek ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Electron Transfer ◽  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Triggering Mechanism ◽  
Reversible Electron Transfer

AMF-responsive doxorubicin loaded β-cyclodextrin-decorated superparamagnetic nanoparticles

2018 ◽  
Vol 42 (1) ◽  
pp. 671-680 ◽  
Author(s):  
Evelyn C. da S. Santos ◽  
Amanda Watanabe ◽  
Maria D. Vargas ◽  
Marcelo N. Tanaka ◽  
Flavio Garcia ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Iron Oxide ◽  
Controlled Release ◽  
Iron Oxide Nanoparticles ◽  
Superparamagnetic Iron Oxide ◽  
Superparamagnetic Nanoparticles ◽  
Alternating Magnetic Field ◽  
Oxide Nanoparticles ◽  
Release System ◽  
Controlled Release System

An alternating magnetic field (AMF)-responsive controlled release system has been developed by the binding of mono-6-deoxy-6-(p-tolylsulfonyl)-β-cyclodextrin (βCD-Ts) onto amine-modified superparamagnetic iron oxide nanoparticles (MNP-NH2), resulting in a MNP-βCD nanocarrier.

The Influence of Coating and Agglomeration on Specific Absorption Rate of Iron Oxide Nanoparticles

2011 ◽  
Author(s):  
Yuan Yuan ◽  
Diana-Andra Borca-Tasciuc
Keyword(s):  
Magnetic Field ◽  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Heat Generation ◽  
Biomedical Applications ◽  
Debye Model ◽  
Generation Rate ◽  
Coated Sample ◽  
Oxide Nanoparticles ◽  
Heat Generation Rate

Magnetic nanofluids can be remotely heated by alternating magnetic field and have significant potential for cancer hyperthermia therapy. The heat generated by magnetic nanoparticles is typically quantified by the specific absorption rate (SAR), which represents the thermal power per unit mass of magnetic material generated in the presence of an alternating magnetic field. During hyperthermia treatment, heat dosage of tumor tissue correlates with slowing tumor growth. The therapeutic ratios of cancer can be increased with the use of biofunctionalized magnetic nanoparticles that have higher SAR for modest amplitudes of magnetic field[1]. Hence, understanding the factors that control the heat generation of magnetic nanoparticle suspensions is important to design fluids with optimized biocompatibility and functionality. In all biomedical applications, the nanoparticles must be coated on the surface to prevent their agglomeration [2], enhance biocompatibility and allow targeting to a specific area. Existing studies have shown that the SAR of nanoparticles may change in the presence of functional coating[3–5]. However, while these studies show that the coating may affect the heat generation rate, there is a limited understanding on the mechanisms that cause that changes of SAR. Hence, it is important to carry out a systematic investigation of nanoparticles similar in size but with different organic coating relevant to biomedical applications to obtain a more complete picture of the mechanisms contributing to changes in SAR. In this work, we present a review of our efforts in this area. Specifically, in our studies we are investigating the correlation between the magnetic and physical properties of commercially available nanoparticles systems and their heat generation rate. The susceptibility and SAR of suspensions of coated and uncoated iron oxide nanoparticles of similar particle size are measured. The coatings selected are highly relevant to biomedical applications and include amine and carboxyl functionalization as well as bioaffine ligands such as protein and biotin. The particle and cluster size was determined from transmission electron microscope (TEM), X-Ray diffraction (XRD) and Dynamic light scattering (DLS). TEM and DLS studies suggested that clusters exist in samples. A summary of all morphological properties together with pH of each suspension is shown in Table.1. The AC magnetic susceptibility of the suspensions was measured as a function of frequency with an in-house made apparatus. Finally SAR was determined by heating the suspension in a commercial induction system and measuring the temperature rise as function of time with a fiber optic sensor. Following these measurements, the SAR values were predicted in two ways: 1) based on measured AC susceptibility and 2) based on particle physical and magnetic properties, starting from Debye model for susceptibility. The normalized predicted and experimental SAR values for all samples are also shown in Table 1. From Table 1, it was found that pH may influence aggregation as described in Ref [6], which indicated that at pH about 2 nanoparticles are highly charged preventing their aggregation while in pH in 6–10 suspensions aggregations are more significant. Normalized SAR of nanoparticle system with aggregations seems to be not related to concentration, different from the well dispersed system[7]. The carboxyl coated sample has smallest diameter and show the lowest SAR, as reported in Ref[8]. The results of suspensions of uncoated iron oxide nanoparticles as well as particles coated with amine groups show that normalized experimental SAR (NSARE) agrees relatively well with calculated SAR using experimental susceptibility (NSARC_χ″E); poor agreement was found when experimental susceptibility was substituted with calculated one (NSART_χ″C) using Debye model, which is developed for non-interacting magnetic particles. These results suggest that the coating do not have a direct effect on SAR. On the other hand, agglomeration, which was present in both samples, may lead to dipolar interaction between nanoparticles and enhancement in magnetic properties and SAR. For carboxyl coated sample which has negligible clustering, showed no temperature increase and zero imaginary part of susceptibility. Therefore, good agreement between Debye-model based predictions of SAR and experimental results were obtained in this sample. However, unexpected results were obtained for bioaffine ligands coated sample, where the experimental SAR values are higher than the SAR values determined based on experimental susceptibility. Protein coated sample, which has the larger clusters among the two samples, has a heat generation rate is 6 times higher than the prediction. Meanwhile, the biotin coated sample which has relatively smaller clusters show only a small increase in heat generation rate. A possible explanation for these results is the loss of superparamagnetic character and an opening in hysteresis loop at test frequency for suspensions with large clusters, which may increase the dissipated power above that produced by the relaxation heat losses [9]. Above results show that coating had little effect on SAR. On the other hand, aggregations and clusters may significantly affect SAR, possibly due to dipolar interaction between nanoparticles in suspensions with relatively small clusters or loss of superparmagnetic characters when very large clusters are present.

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