superparamagnetic nanoparticles
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Separations of bare superparamagnetic magnetite nanoparticles (BSPMNPs, approx. 11 nm diameter) was performed using non-complexing (nitrate) and complexing (chloride, citrate and phosphate) electrolyte ions with additions of tetramethylammonium hydroxide (TMAOH), which is commonly applied to control the synthesis of stable iron oxides. The use of TMAOH as a background electrolyte (BGE) additive for capillary electrophoresis (CE) separations provided for the first time electropherograms of BSPMNPs exhibiting symmetrical and highly reproducible peaks, free of spurious spikes characteristic of nanoparticle clusters. Consequently, accurate determination of the electrophoretic effective mobility of BSPMNPs was possible, yielding a value of -3.345E-08 m2 V-1 s-1 (relative standard deviation (RSD) of 0.500%). The obtained mobilities of BSPMNPs in the presence of various electrolyte ions show that the degree of complexation with the surface of BSPMNPs follows the order chloride < citrate < phosphate, correlating with the stabilities of Fe(III) complexes with the respective anions. Finally, bare and carboxylated iron oxide nanoparticles were successfully separated in only 10 min using 10 mM Tris-nitrate containing 20 mM of TMAOH as electrolyte. Our findings show that simple and rapid CE experiments are an excellent tool to characterise and monitor properties and interactions of iron oxide nanoparticles with other molecules for surface modification purposes.
Biocompatibility, safety, and risk assessments of superparamagnetic iron oxide nanoparticles (SPIONs) are of the highest priority in researching their application in biomedicine. One improvement in the biological properties of SPIONs may be achieved by different functionalization and surface modifications. This study aims to investigate how a different surface functionalization of SPIONs - uncoated, coated with d-mannose, or coated with poly-l-lysine - affects biocompatibility. We sought to investigate murine neural stem cells (NSCs) as important model system for regenerative medicine. To reveal the possible mechanism of toxicity of SPIONs on NSCs, levels of reactive oxygen species, intracellular glutathione, mitochondrial membrane potential, cell-membrane potential, DNA damage, and activities of SOD and GPx were examined. Even in cases where reactive oxygen species levels were significantly lowered in NSCs exposed to SPIONs, we found depleted intracellular glutathione levels, altered activities of SOD and GPx, hyperpolarization of the mitochondrial membrane, dissipated cell-membrane potential, and increased DNA damage, irrespective of the surface coating applied for SPION stabilization. Although surface coating should prevent the toxic effects of SPIONs, our results showed that all of the tested SPION types affected the NSCs similarly, indicating that mitochondrial homeostasis is their major cellular target. Despite the claimed biomedical benefits of SPIONs, the refined determination of their effects on various cellular functions presented in this work highlights the need for further safety evaluations. This investigation helps to fill the knowledge gaps on the criteria that should be considered in evaluating the biocompatibility and safety of novel nanoparticles.
- MeSH
- antioxidancia farmakologie MeSH
- dextrany farmakologie MeSH
- hydrodynamika MeSH
- magnetické nanočástice MeSH
- membránové potenciály účinky léků MeSH
- membránový potenciál mitochondrií účinky léků MeSH
- myši inbrední C57BL MeSH
- nanočástice chemie ultrastruktura MeSH
- nervové kmenové buňky účinky léků patologie MeSH
- oxidační stres účinky léků MeSH
- poškození DNA MeSH
- reaktivní formy kyslíku metabolismus MeSH
- statická elektřina MeSH
- viabilita buněk účinky léků MeSH
- železité sloučeniny farmakologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
In recent years, Fe oxide nanoparticles have been increasingly used in a wide range of biomedical applications, including magnetic resonance imaging, magnetic hyperthermia, targeted drug and gene delivery, cell tracking and magnetic cell separation. Although the number of studies examining the toxicity of Fe oxide nanoparticles is growing exponentially, the in-depth toxicity studies are scanty and the mechanisms underlying their cytotoxicity remain still mostly unclear. This review focuses on the assessment of the in vitro and in vivo toxicity of Fe oxide nanoparticles and discusses the biological processes underlying their toxicity including cellular uptake, production of reactive O species, modulation of actin and microtubular cytoskeleton, DNA damage and activation of intracellular signalling pathways. The significance of the proteins associated with Fe oxide nanoparticles and assays for assessing their cytotoxicity are also considered. We have tested cytotoxic effects of silica-coated Fe oxide nanoparticles on human lung adenocarcinoma, epithelial cell line A549 using the xCELLigence system for label-free and real-time monitoring of cell viability.
- Klíčová slova
- MNPs, SPIONs,
- MeSH
- kovové nanočástice chemie škodlivé účinky terapeutické užití toxicita MeSH
- lidé MeSH
- magnetické nanočástice * chemie škodlivé účinky terapeutické užití toxicita MeSH
- oxidační stres MeSH
- techniky in vitro MeSH
- testy toxicity * MeSH
- viabilita buněk MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
Arsenates, when present in water resources, constitute a risk to human health. In order to remove them, various technologies have been developed; out of them, sorption approach is widely adopted employing a wide spectrum of suitable sorbent materials. Nanoparticles of iron oxide are frequently used due to a high surface area and ability to control them by external magnetic field. In this work, we report on a simple and cheap synthesis of ultrafine iron(III) oxide nanoparticles with a narrow size distribution and their exploitation in the field of arsenate removal from aqueous environment. It is shown that the adsorption capacity is enhanced by a mesoporous nature of nanoparticle arrangement in their system due to strong magnetic interactions they evolve between nanoparticles. A complete arsenate removal is achieved at Fe/As ratio equal to ∼20/1 and at pH in the range from 5 to 7.6. Under these conditions, the arsenates are completely removed within several minutes of treatment. Among iron-oxide-based nanosystems synthesized and employed in arsenate remediation issues so far, our assembly of iron(III) oxide nanoparticles shows the highest Freundlich adsorption coefficient and equilibrium sorption capacity under conditions maintained. Taking into account simple and low-cost preparation procedure, product high yields, almost monodispersed character, room-temperature superparamagnetic behavior, and strong magnetic response under small applied magnetic fields, the synthesized iron(III) oxide nanoparticles can be regarded as a promising candidate for exploitation in the field of removing undesired toxic pollutants from various real water systems.
OBJECTIVE: Cell therapies have emerged as a promising approach in medicine. The basis of each therapy is the injection of 1-100×10(6) cells with regenerative potential into some part of the body. Mesenchymal stromal cells (MSCs) are the most used cell type in the cell therapy nowadays, but no gold standard for the labeling of the MSCs for magnetic resonance imaging (MRI) is available yet. This work evaluates our newly synthesized uncoated superparamagnetic maghemite nanoparticles (surface-active maghemite nanoparticles - SAMNs) as an MRI contrast intracellular probe usable in a clinical 1.5 T MRI system. METHODS: MSCs from rat and human donors were isolated, and then incubated at different concentrations (10-200 μg/mL) of SAMN maghemite nanoparticles for 48 hours. Viability, proliferation, and nanoparticle uptake efficiency were tested (using fluorescence microscopy, xCELLigence analysis, atomic absorption spectroscopy, and advanced microscopy techniques). Migration capacity, cluster of differentiation markers, effect of nanoparticles on long-term viability, contrast properties in MRI, and cocultivation of labeled cells with myocytes were also studied. RESULTS: SAMNs do not affect MSC viability if the concentration does not exceed 100 μg ferumoxide/mL, and this concentration does not alter their cell phenotype and long-term proliferation profile. After 48 hours of incubation, MSCs labeled with SAMNs show more than double the amount of iron per cell compared to Resovist-labeled cells, which correlates well with the better contrast properties of the SAMN cell sample in T2-weighted MRI. SAMN-labeled MSCs display strong adherence and excellent elasticity in a beating myocyte culture for a minimum of 7 days. CONCLUSION: Detailed in vitro tests and phantom tests on ex vivo tissue show that the new SAMNs are efficient MRI contrast agent probes with exclusive intracellular uptake and high biological safety.
- MeSH
- buněčný tracking metody MeSH
- dextrany chemie farmakokinetika toxicita MeSH
- fyziologie buňky účinky léků MeSH
- kontrastní látky chemie farmakokinetika toxicita MeSH
- krysa rodu rattus MeSH
- kultivované buňky MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- magnetické nanočástice chemie toxicita MeSH
- mezenchymální kmenové buňky chemie cytologie účinky léků metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
Introduction: Conventional biopsy, based on extraction from a tumor of a solid tissue specimen requiring needles, endoscopic devices, excision or surgery, is at risk of infection, internal bleeding or prolonged recovery. A non-invasive liquid biopsy is one of the greatest axiomatic consequences of the identification of circulating tumor DNA (ctDNA) as a replaceable surgical tumor bioQpsy technique. Most of the literature studies thus far presented ctDNA detection at almost final stage III or IV of cancer, where the treatment option or cancer management is nearly impossible for diagnosis. Objective: Hence, this paper aims to present a simulation study of extraction and separation of ctDNA from the blood plasma of cancer patients of stage I and II by superparamagnetic (SPM) bead particles in a microfluidic platform for early and effective cancer detection. Method: The extraction of ctDNA is based on microfiltration of particle size to filter some impurities and thrombocytes plasma, while the separation of ctDNA is based on magnetic manipulation to high yield that can be used for the upstream process. Result: Based on the simulation results, an average of 5.7 ng of ctDNA was separated efficiently for every 10 μL blood plasma input and this can be used for early analysis of cancer management. The particle tracing module from COMSOL Multiphysics traced ctDNA with 65.57% of sensitivity and 95.38% of specificity. Conclusion: The findings demonstrate the ease of use and versatility of a microfluidics platform and SPM bead particles in clinical research related to the preparation of biological samples. As a sample preparation stage for early analysis and cancer diagnosis, the extraction and separation of ctDNA is most important, so precision medicine can be administered.
- MeSH
- cirkulující nádorová DNA * MeSH
- lidé MeSH
- magnetické nanočástice oxidů železa MeSH
- mikrofluidika MeSH
- nádory * diagnóza MeSH
- tekutá biopsie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This review is focused on identification of bacterial species by their antigenes by barcoding oligonucleotides by application of magnetic micro and nanoparticles. In the first part of this review is discussed the structures and types of magnetic particles and their synthesis. In the next and the most important part we described the principle and the existing status of barcoding system and antigenes markers for identification of organisms such as animals, plants and microorganisms.
- Klíčová slova
- biobarcode assay, magnetické mikročástice, DNA barkódování,
- MeSH
- kovové nanočástice * MeSH
- magnetické nanočástice MeSH
- magnetismus * MeSH
- molekulární sondy - techniky MeSH
- oligonukleotidy MeSH
- protilátky MeSH
- sekvenční analýza hybridizací s uspořádaným souborem oligonukleotidů MeSH
- taxonomické DNA čárové kódování * metody využití MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
Due to its native origin, excellent biocompatibility and biodegradability, hyaluronan (HA) represents an attractive polymer for superparamagnetic iron oxide nanoparticles (SPION) coating. Herein, we report HA polymeric micelles encapsulating oleic acid coated SPIONs, having a hydrodynamic size of about 100 nm and SPION loading capacity of 1-2 wt %. The HA-SPION polymeric micelles were found to be selectively cytotoxic toward a number of human cancer cell lines, mainly those of colon adenocarcinoma (HT-29). The selective inhibition of cell growth was even observed when the SPION loaded HA polymeric micelles were incubated with a mixture of control and cancer cells. The selective in vitro inhibition could not be connected with an enhanced CD44 uptake or radical oxygen species formation and was rather connected with a different way of SPION intracellular release. While aggregated iron particles were visualized in control cells, nonaggregated solubilized iron oxide particles were detected in cancer cells. In vivo SPION accumulation in intramuscular tumor following an intravenous micelle administration was confirmed by magnetic resonance (MR) imaging and histological analysis. Having a suitable hydrodynamic size, high magnetic relaxivity, and being cancer specific and able to accumulate in vivo in tumors, SPION-loaded HA micelles represent a promising platform for theranostic applications.
- MeSH
- buňky Swiss 3T3 MeSH
- Caco-2 buňky MeSH
- HCT116 buňky MeSH
- kovové nanočástice aplikace a dávkování chemie MeSH
- kyselina hyaluronová aplikace a dávkování chemie MeSH
- lidé MeSH
- mezenchymální kmenové buňky účinky léků MeSH
- MFC-7 buňky MeSH
- micely * MeSH
- myši MeSH
- nosiče léků aplikace a dávkování chemie MeSH
- polymery aplikace a dávkování chemie MeSH
- potkani inbrední BN MeSH
- potkani inbrední LEW MeSH
- protinádorové látky aplikace a dávkování chemie MeSH
- výsledek terapie MeSH
- xenogenní modely - testy protinádorové aktivity metody MeSH
- železité sloučeniny aplikace a dávkování chemie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Online electrokinetic preconcentration of magnetite core/carboxylic shell nanoparticles (MNPs) was studied by capillary electrophoresis using reversed and suppressed electroosmotic flow (EOF). 50mM sodium borate pH 9.5 was used as a background electrolyte. CTAB additive was used to reverse EOF and commercial polyvinylalcohol (PVA)-coated capillaries were used for EOF suppressed studies. Analyses in PVA-coated capillaries were more reproducible and therefore, the setup was further optimized in terms of water plug injection time, sample injection time, and voltage. Within the optimal conditions, the MNPs dispersed in water are electrokinetically loaded into BGE consisting of 50mM sodium borate pH 9.5 using -10kV for 120s. In comparison with the hydrodynamic injection of 5s by 50mbar, the electrokinetic injection allows 860-fold preconcentration of MNPs.
Magnetic γ-Fe2O3/CeO2 nanoparticles were obtained by precipitation of Ce(NO3)3 with ammonia in the presence of γ-Fe2O3 seeds. The formation of CeO2 nanoparticles on the seeds was confirmed by transmission electron microscopy linked with selected area electron diffraction, energy-dispersive X-ray spectroscopy, electron energy loss spectroscopy, and dynamic light scattering. The γ-Fe2O3/CeO2 particle surface was functionalized with PEG-neridronate to improve the colloidal stability in PBS and biocompatibility. Chemical and in vitro biological assays proved that the nanoparticles, due to the presence of cerium oxide, effectively scavenged radicals, thus decreasing oxidative stress in the model cell line. PEG functionalization of the nanoparticles diminished their in vitro aggregation and facilitated lysosomal cargo degradation in cancer cells during autophagy, which resulted in concentration-dependent cytotoxicity of the nanoparticles. Finally, the iron oxide core allowed easy magnetic separation of the particles from liquid media and may enable monitoring of nanoparticle biodistribution in organisms using magnetic resonance imaging.
