Magnetic nanorobots offer wireless navigation capability in hard-to-reach areas of the human body for targeted therapy and diagnosis. Though in vivo imaging is required for guidance of the magnetic nanorobots toward the target areas, most of the imaging techniques are inadequate to reveal the potential locomotion routes. This work proposes the use of radiopaque magnetic nanorobots along with microcomputed tomography (microCT) for localized in vivo imaging applications. The nanorobots consist of a contrast agent, barium sulfate (BaSO4 ), magnetized by the decoration of magnetite (Fe3 O4 ) particles. The magnetic features lead to actuation under rotating magnetic fields and enable precise navigation in a microfluidic channel used to simulate confined spaces of the body. In this channel, the intrinsic radiopacity of the nanorobots also provides the possibility to reveal the internal structures by X-ray contrast. Furthermore, in vitro analysis indicates nontoxicity of the nanorobots. In vivo experiments demonstrate localization of the nanorobots in a specific part of the gastrointestinal (GI) tract upon the influence of the magnetic field, indicating the efficient control even in the presence of natural peristaltic movements. The nanorobots reported here highlight that smart nanorobotic contrast agents can improve the current imaging-based diagnosis techniques by providing untethered controllability in vivo.
Chemotherapy is the most prominent route in cancer therapy for prolonging the lifespan of cancer patients. However, its non-target specificity and the resulting off-target cytotoxicities have been reported. Recent in vitro and in vivo studies using magnetic nanocomposites (MNCs) for magnetothermal chemotherapy may potentially improve the therapeutic outcome by increasing the target selectivity. In this review, magnetic hyperthermia therapy and magnetic targeting using drug-loaded MNCs are revisited, focusing on magnetism, the fabrication and structures of magnetic nanoparticles, surface modifications, biocompatible coating, shape, size, and other important physicochemical properties of MNCs, along with the parameters of the hyperthermia therapy and external magnetic field. Due to the limited drug-loading capacity and low biocompatibility, the use of magnetic nanoparticles (MNPs) as drug delivery system has lost traction. In contrast, MNCs show higher biocompatibility, multifunctional physicochemical properties, high drug encapsulation, and multi-stages of controlled release for localized synergistic chemo-thermotherapy. Further, combining various forms of magnetic cores and pH-sensitive coating agents can generate a more robust pH, magneto, and thermo-responsive drug delivery system. Thus, MNCs are ideal candidate as smart and remotely guided drug delivery system due to a) their magneto effects and guide-ability by the external magnetic fields, b) on-demand drug release performance, and c) thermo-chemosensitization under an applied alternating magnetic field where the tumor is selectively incinerated without harming surrounding non-tumor tissues. Given the important effects of synthesis methods, surface modifications, and coating of MNCs on their anticancer properties, we reviewed the most recent studies on magnetic hyperthermia, targeted drug delivery systems in cancer therapy, and magnetothermal chemotherapy to provide insights on the current development of MNC-based anticancer nanocarrier.
- MeSH
- indukovaná hypertermie * metody MeSH
- lékové transportní systémy metody MeSH
- lidé MeSH
- magnetické pole MeSH
- magnetismus MeSH
- nádory * farmakoterapie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Conventional immunochemical methods used in clinical analysis are often not sensitive enough for early-stage diagnosis, resulting in the need for novel assay formats. Here, we provide a detailed comparison of the effect of different labels and solid supports on the performance of heterogeneous immunoassays. When comparing three types of streptavidin-modified labels─horseradish peroxidase, carboxyfluorescein, and photon-upconversion nanoparticles (UCNPs)─UCNPs led to the most sensitive and robust detection of the cancer biomarker prostate-specific antigen. Additionally, we compared the immunoassay formats based on conventional microtiter plates and magnetic microbeads (MBs). In both cases, the highest signal-to-background ratios and the lowest limits of detection (LODs) were obtained by using the UCNP labels. The MB-based upconversion-linked immunosorbent assay carried out with a preconcentration step provided the lowest LOD of 0.46 pg/mL in serum. The results demonstrate that the use of UCNPs and MBs can significantly improve the sensitivity and working range of heterogeneous immunoassays for biomarker detection.
- MeSH
- imunoanalýza metody MeSH
- imunosorbenty * MeSH
- lidé MeSH
- limita detekce MeSH
- magnetismus MeSH
- nanočástice * MeSH
- streptavidin MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Cíl: Využití magnetických nanočástic jako multifunkčních materiálů pro současnou diagnostiku a terapii. Úvod: Rychlý vývoj v oblasti nanotechnologií usnadnil vznik nových nanomateriálů. S tímto trendem je také spojen zvýšený zájem o nano a mikro systémy tvořené magnetickými nosiči. Spojením magnetického nosiče s biologicky aktivní látkou lze dosáhnout unikátních vlastností využitelných v mnoha oblastech biotechnologie a medicíny. Popis problematiky: Mezi nejvíce studované materiály se řadí magnetické nanočástice tvořené oxidy železa. V současné době se velká pozornost věnuje superparamagnetickým nanočásticím oxidů železa, tzv. SPIONs (superparamagnetic iron oxide nanoparticles), které pod určitou hranicí velikosti (1–20 nm) vykazují jednodoménový charakter, který způsobuje jev zvaný superparamagnetismus. Vedle velikosti částic jsou důležité povrchové vlastnosti. Velikost povrchu (řádově 100 m2/g) umožňuje jeho modifikaci, čímž je zvýšena biokompatibilita částic a snížena toxicita. Magnetické nanočástice mají značný potenciál využití v biomedicínských aplikacích, a to zejména v oblasti teranostiky. V současnosti jsou nanočásticové systémy studovány zejména k zesílení kontrastu u zobrazovacích technik MRI, v pozitronové emisní tomografii, případně lze využít přeměny magnetické energie na energii tepelnou, čehož využívá metoda zvaná hypertermie. Další využití představuje separace, analýza buněk nebo značení buněk, které se zdá být slibné v oblasti zobrazovacích metod. Závěr: Jak se ukazuje, problematika uplatnění magnetických nanočástic v lékařství je rozsáhlá. Prvotní výzvou je syntéza těchto nanočástic, přičemž existuje řada postupů, které poskytují nanočástice o různých vlastnostech. Kvůli povaze nanočástic je také nutné věnovat velikou pozornost jejich stabilizaci, aby se předcházelo agregaci a v případě jejich použití jakožto nosiče je taktéž nutné vyřešit problém zachycení požadované látky. Tyto problémy jsou stále předmětem výzkumu, ale i přes tyto obtíže představují magnetické nanočástice potenciální mocný nástroj pro současnou diagnostiku a terapii.
Aim: Application of magnetic nanoparticles as multimodal materials for current diagnostics and therapy. Introduction: Rapid developments in nanotechnology have facilitated the emergence of new nanomaterials. This trend is also associated with an increased interest in nano and micro systems consisting of magnetic carriers. By combining a magnetic vector with a biologically active substance, unique properties can be achieved which can be used in many areas of biotechnology and medicine. Issues description: The most common materials are magnetic nanoparticles synthesised of iron oxides. Currently, widely studied are superparamagnetic iron oxide nanoparticles, socalled SPIONs, which below a certain size range (1–20 nm) exhibit a single-domain character, which causes a phenomenon called superparamagnetism. In addition to particle size, surface properties are important. The surface size (in the order of 100 m2/g) allows its modification, which increases the biocompatibility of particles and reduces toxicity. Magnetic nanoparticles have considerable potential for use in biomedical applications, especially in the field of teranostics. At present, nanoparticle systems are studied mainly as contrast agents in MR imaging techniques, in positron emission tomography, or the conversion of magnetic energy into thermal energy can be used, which uses a method called hyperthermia. Other uses include separation, cell analysis, or cell labeling, which appear promising in imaging methods. Conclusion: As shown, the application of magnetic nanoparticles in medicine is extensive. The primary challenge is the synthesis of these nanoparticles, and there are a number of processes that provide nanoparticles with different properties. Due to the nature of nanoparticles, the care must also be taken to stabilize them in order to prevent aggregation, and in the case of their use as carriers, it is also necessary to solve the problem of entrapment of the desired substance. These problems are still the subject of research, but despite these difficulties, magnetic nanoparticles are a potentially powerful tool for current diagnostics and therapy.
- MeSH
- indukovaná hypertermie MeSH
- kontrastní látky chemie terapeutické užití MeSH
- lidé MeSH
- magnetické nanočástice oxidů železa * chemie MeSH
- magnetické nanočástice chemie terapeutické užití MeSH
- magnetismus MeSH
- multimodální zobrazování MeSH
- pozitronová emisní tomografie MeSH
- teranostická nanomedicína MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
Contactless digital tags are increasingly penetrating into many areas of human activities. Digitalization of our environment requires an ever growing number of objects to be identified and tracked with machine-readable labels. Molecules offer immense potential to serve for this purpose, but our ability to write, read, and communicate molecular code with current technology remains limited. Here we show that magnetic patterns can be synthetically encoded into stable molecular scaffolds with paramagnetic lanthanide ions to write digital code into molecules and their mixtures. Owing to the directional character of magnetic susceptibility tensors, each sequence of lanthanides built into one molecule produces a unique magnetic outcome. Multiplexing of the encoded molecules provides a high number of codes that grows double-exponentially with the number of available paramagnetic ions. The codes are readable by nuclear magnetic resonance in the radiofrequency (RF) spectrum, analogously to the macroscopic technology of RF identification. A prototype molecular system capable of 16-bit (65,535 codes) encoding is presented. Future optimized systems can conceivably provide 64-bit (~10^19 codes) or higher encoding to cover the labelling needs in drug discovery, anti-counterfeiting and other areas.
- MeSH
- lanthanoidy * MeSH
- lidé MeSH
- magnetická rezonanční spektroskopie MeSH
- magnetismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Background: Intravascular delivery of nanoparticles for theranostic application permits direct interaction of nanoparticles and vascular cells. Since vascular smooth muscle cells (VSMCs), the major components of the vascular wall, are constantly subjected to mechanical stimulation from hemodynamic influence, we asked whether cyclic strain may modulate internalization of magnetic nanoparticles (MNPs) by cultured VSMCs. Methods: Cyclic strain (1 Hz and 10%) was applied with Flexcell system in cultured VSMCs from rats, with cell-associated MNPs (MNPcell) determined by a colorimetric iron assay. Transmission and scanning electron microscopy were used for morphology studies. Confocal microscopy was used to demonstrate distribution of actin assembly in VSMCs. Results: Incubation of poly(acrylic acid) (PAA)-coated MNPs with VSMCs for 4 h induced microvilli formation and MNP internalization. Application of cyclic strain for 4-12 h significantly reduced MNPcell by up to 65% (p < 0.05), which was associated with blunted microvilli and reduced vesicle size/cell, but not vesicle numbers/cell. Confocal microscopy demonstrated that both cyclic strain and fibronectin coating of the culture plate reduced internalized MNPs, which were co-localized with vinculin. Furthermore, cytochalasin D reduced MNPcell, suggesting a role of actin polymerization in MNP uptake by VSMCs; however, a myosin II ATPase inhibitor, blebbistatin, exhibited no effect. Cyclic strain also attenuated uptake of PAA-MNPs by LN-229 cells and uptake of poly-L-lysine-coated MNPs by VSMCs. Conclusion: In such a dynamic milieu, cyclic strain may impede cellular internalization of nanocarriers, which spares the nanocarriers and augments their delivery to the target site in the lumen of vessels or outside of the circulatory system.
- MeSH
- biologický transport MeSH
- buněčné linie MeSH
- krysa rodu rattus * MeSH
- magnetismus MeSH
- mechanický stres MeSH
- myocyty hladké svaloviny metabolismus MeSH
- nanočástice * metabolismus MeSH
- svaly hladké cévní MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus * MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Magnetic particles play an important role in current technology, and this field of technology extends to a broader progression. The term magnetic particles typically cover the paramagnetic particles and super-paramagnetic particles. Various materials like iron oxide are common, but other materials are available as well; a survey of such materials has been included in this work. They can serve for technological purposes like separation and isolation of chemical products or toxic waste, their use in the diagnosis of pathologies, drug delivery and other similar applications. In this review, biosensors, bioanalytical devices and bioassays, have been discussed. Materials for magnetic particles preparation, methods of assay, biosensors and bioassays working in stationary as well as flow-through arrangements are described here. A survey of actual literature has been provided as well.
- MeSH
- biosenzitivní techniky * MeSH
- biotest MeSH
- lékové transportní systémy MeSH
- lidé MeSH
- magnetické jevy MeSH
- magnetismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Controlled pulmonary drug delivery systems employing non-spherical particles as drug carriers attract considerable attention nowadays. Such anisotropic morphologies may travel deeper into the lung airways, thus enabling the efficient accumulation of therapeutic compounds at the point of interest and subsequently their sustained release. This study focuses on the fabrication of electrospun superparamagnetic polymer-based biodegradable microrods consisting of poly(l-lactide) (PLLA), polyethylene oxide (PEO) and oleic acid-coated magnetite nanoparticles (OA·Fe3O4). The production of magnetite-free (0% wt. OA·Fe3O4) and magnetite-loaded (50% and 70% wt. Fe3O4) microrods was realized upon subjecting the as-prepared electrospun fibers to UV irradiation, followed by sonication. Moreover, drug-loaded microrods were fabricated incorporating methyl 4-hydroxybenzoate (MHB) as a model pharmaceutical compound and the drug release profile from both, the drug-loaded membranes and the corresponding microrods was investigated in aqueous media. In addition, the magnetic properties of the produced materials were exploited for remote induction of hyperthermia under AC magnetic field, while the possibility to reduce transport losses and enhance the targeted delivery to lower airways by manipulation of the airborne microrods by DC magnetic field was also demonstrated.
- Klíčová slova
- relaxační čas,
- MeSH
- bezpečnost MeSH
- cévy diagnostické zobrazování patologie MeSH
- kontraindikace MeSH
- kontrastní látky MeSH
- lidé MeSH
- magnetická rezonanční angiografie metody MeSH
- magnetická rezonanční tomografie * metody přístrojové vybavení MeSH
- magnetické jevy MeSH
- magnetické pole MeSH
- magnetismus MeSH
- nemoci cév diagnostické zobrazování patologie MeSH
- nemoci srdce diagnostické zobrazování klasifikace MeSH
- protony MeSH
- srdce * diagnostické zobrazování patofyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Cobalt oxide nanoparticles were prepared via green chemistry route and fully characterized by Field Emission Scanning Electron Microscope (FESEM), Energy-dispersive X-ray spectroscopy (EDAX), X-ray diffraction (XRD), High-resolution transmission electron microscopy (HRTEM) and Transmission electron microscopy (TEM) analyses; the CoO and Co3O4 nanoparticles, in sheet-shaped cobalt oxide form, ensued simultaneously in one step. The varying concentrations of NPs were analyzed via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test on the cancer cell line (U87) which revealed that with increasing concentration of cobalt oxide nanoparticles, the survival rate of U87 tumor cells decreases; IC50 of nanoparticles being ~ 55 µg/ml-1.
- MeSH
- antibakteriální látky chemie MeSH
- difrakce rentgenového záření MeSH
- inhibiční koncentrace 50 MeSH
- kobalt chemie MeSH
- koncentrace vodíkových iontů MeSH
- kovové nanočástice chemie MeSH
- lidé MeSH
- magnetismus MeSH
- mikrobiální testy citlivosti MeSH
- nádorové buněčné linie MeSH
- nanomedicína metody MeSH
- nanotechnologie metody MeSH
- oxidy chemie MeSH
- povrchově aktivní látky MeSH
- protinádorové látky farmakologie MeSH
- rostlinné extrakty MeSH
- rozmarýn MeSH
- rozpustnost MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- technologie zelené chemie metody MeSH
- teplota MeSH
- tetrazoliové soli chemie MeSH
- thiazoly chemie MeSH
- transmisní elektronová mikroskopie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
