Hybrid nanoparticles
Dotaz
Zobrazit nápovědu
The use of organic-inorganic hybrid nanocarriers for controlled release of anticancer drugs has been gained a great interest, in particular, to improve the selectivity and efficacy of the drugs. In this study, iron oxide nanoparticles were prepared then surface modified via diazonium chemistry and coated with chitosan, and its derivative chitosan-grafted polylactic acid. The purpose was to increase the stability of the nanoparticles in physiological solution, heighten drug-loading capacity, prolong the release, reduce the initial burst effect and improve in vitro cytotoxicity of the model drug doxorubicin. The materials were characterized by DLS, ζ-potential, SEM, TGA, magnetization curves and release kinetics studies. Results confirmed the spherical shape, the presence of the coat and the advantages of using chitosan, particularly its amphiphilic derivative, as a coating agent, thereby surpassing the qualities of simple iron oxide nanoparticles. The coated nanoparticles exhibited great stability and high encapsulation efficiency for doxorubicin, at over 500μg per mg of carrier. Moreover, the intensity of the initial burst was clearly diminished after coating, hence represents an advantage of using the hybrid system over simple iron oxide nanoparticles. Cytotoxicity studies demonstrate the increase in cytotoxicity of doxorubicin when loaded in nanoparticles, indirectly proving the role played by the carrier and its surface properties in cell uptake.
- MeSH
- chitosan chemie MeSH
- doxorubicin aplikace a dávkování MeSH
- HeLa buňky MeSH
- lidé MeSH
- nanočástice chemie MeSH
- nosiče léků chemie MeSH
- povrchové vlastnosti MeSH
- protinádorové látky aplikace a dávkování MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The preparation of light-activated hybrid antibacterial agent combining the porphyrin molecules, bound to the silver nanoparticles (AgNPs) surface is reported. AgNPs were synthesized by N-methyl-2-pyrrolidone-initiated reduction without additional reducing agents. The chemical structure of protoporphyrin IX was modified with the aim to introduce thiol groups. The size distribution and shape features of AgNPs were checked using TEM and HRTEM microscopies. The introduction of thiol groups into the porphyrin was proved by IR spectroscopy. The AgNPs-porphyrin binding was performed in solution and confirmed by fluorescence quenching, Raman spectroscopy and energy-filtered transmission electron microscopy (EFTEM). The antibacterial tests were performed against S. epidermidis and E. coli upon to LED illumination and in the dark. The synergetic effect of AgNPs and porphyrin as well as light activation of the created antibacterial conjugates were observed.
- MeSH
- antibakteriální látky chemická syntéza farmakologie MeSH
- Escherichia coli účinky léků MeSH
- kovové nanočástice chemie ultrastruktura MeSH
- luminiscence MeSH
- mikrobiální testy citlivosti MeSH
- porfyriny chemická syntéza chemie farmakologie MeSH
- Staphylococcus epidermidis účinky léků MeSH
- stříbro chemie farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
The preservation of enzymatic activity is a fundamental requirement for exploiting hybrid nano-bio-conjugates, and the control over protein-nanoparticle interactions, leading to stable and catalytically active hybrids, represents the key for designing new biosensing platforms. In this scenario, surface active maghemite nanoparticles (SAMNs) represent a new class of naked magnetic nanoparticles, displaying peculiar electrocatalytic features and the ability to selectively bind proteins. Recombinant aminoaldehyde dehydrogenase from tomato (SlAMADH1) was used as a model protein, and successfully immobilized by self-assembly on the surface of naked SAMNs, where its enzymatic activity resulted preserved for more than 6 months. The hybrid nanomaterial (SAMN@SlAMADH1) was characterized by UV-Vis spectroscopy, mass spectrometry, and TEM microscopy, and applied for the development of a biosensor for the determination of aminoaldehydes in alcoholic beverages. Measurements were carried out in a low volume electrochemical flow cell comprising a SAMN modified carbon paste electrode for the coulometric determination of the NADH produced during the enzymatic catalysis. The present findings, besides representing the first example of an electrochemical biosensor for aminoaldehydes in an alcoholic matrix, open the door to the use of immobilized enzymes on naked metal oxides nanomaterials for biosensing.
- MeSH
- aldehyddehydrogenasa metabolismus MeSH
- aldehydy analýza MeSH
- biosenzitivní techniky * MeSH
- elektrochemické techniky MeSH
- enzymy imobilizované metabolismus MeSH
- kovové nanočástice chemie MeSH
- propylaminy analýza MeSH
- Solanum lycopersicum enzymologie MeSH
- železité sloučeniny chemie MeSH
- Publikační typ
- časopisecké články MeSH
The present work introduces combination of superparamagnetic iron oxides (SPIONs) and hexamolybdenum cluster ([{Mo6I8}I6]2-) units within amino-decorated silica nanoparticles (SNs) as promising design of the hybrid SNs as efficient cellular contrast and therapeutic agents. The heating generated by SNs doped with SPIONs (Fe3O4@SNs) under alternating magnetic field is characterized by high specific absorption rate (SAR = 446 W/g). The cluster units deposition onto both Fe3O4@SNs and "empty" silica nanoparticles (SNs) results in Fe3O4@SNs[{Mo6I8}I6] and SNs[{Mo6I8}I6] with red cluster-centered luminescence and ability to generate reactive oxygen species (ROS) under the irradiation. The monitoring of spin-trapped ROS by ESR spectroscopy technique indicates that the ROS-generation decreases in time for SNs[{Mo6I8}I6] and [{Mo6I8}I6]2- in aqueous solutions, while it remains constant for Fe3O4@SNs[{Mo6I8}I6]. The cytotoxicity is low for both Fe3O4@SNs[{Mo6I8}I6] and SNs[{Mo6I8}I6], while the flow cytometry indicates preferable cellular uptake of the former versus the latter type of the nanoparticles. Moreover, entering into nucleus along with cytoplasm differentiates the intracellular distribution of Fe3O4@SNs[{Mo6I8}I6] from that of SNs[{Mo6I8}I6], which remain in the cell cytoplasm only. The exceptional behavior of Fe3O4@SNs[{Mo6I8}I6] is explained by residual amounts of iron ions at the silica surface.
The combination of different nanomaterials has been investigated during the past few decades and represents an exciting challenge for the unexpected emerging properties of the resulting nano-hybrids. Spermidine (Spd), a biogenic polyamine, has emerged as a useful functional monomer for the development of carbon quantum dots (CQDs). Herein, an electrostatically stabilized ternary hybrid, constituted of iron oxide-DNA (the core) and spermidine carbon quantum dots (CQDSpds, the shell), was self-assembled and fully characterized. The as-obtained nano-hybrid was tested on HeLa cells to evaluate its biocompatibility as well as cellular uptake. Most importantly, besides being endowed by the magnetic features of the core, it displayed drastically enhanced fluorescence properties in comparison with parent CQDSpds and it is efficiently internalized by HeLa cells. This novel ternary nano-hybrid with multifaceted properties, ranging from fluorescence to superparamagnetism, represents an interesting option for cell tracking.
- MeSH
- biotechnologie MeSH
- fluorescence MeSH
- HeLa buňky MeSH
- kvantové tečky chemie metabolismus MeSH
- lidé MeSH
- nanostruktury chemie MeSH
- polyaminy chemie metabolismus MeSH
- statická elektřina MeSH
- uhlík chemie metabolismus MeSH
- železité sloučeniny chemie metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
This review (with 129 refs) summarizes the progress in electrochemical immunoassays combined with magnetic particles that was made in the past 5 years. The specifity of antibodies linked to electrochemical transduction (by amperometry, voltammetry, impedimetry or electrochemiluminescence) gains further attractive features by introducing magnetic nanoparticles (MNPs). This enables fairly easy preconcentration of analytes, minimizes matrix effects, and introduces an appropriate label. Following an introduction into the fundamentals of electrochemical immunoassays and on nanomaterials for respective uses, a large chapter addresses method for magnetic capture and preconcentration of analytes. A next chapter discusses commonly used labels such as dots, enzymes, metal and metal oxide nanoparticles and combined clusters. The large field of hybrid nanomaterials for use in such immunoassays is discussed next, with a focus on MNPs composites with various kinds of graphene variants, polydopamine, noble metal nanoparticles or nanotubes. Typical applications address clinical markers (mainly blood and urine parameters), diagnosis of cancer (markers and cells), detection of pathogens (with subsections on viruses and bacteria), and environmental and food contaminants as toxic agents and pesticides. A concluding section summarizes the present status, current challenges, and highlights future trends. Graphical abstract Magnetic nanoparticles (MNP) with antibodies (Ab) capture and preconcentrate analyte from sample (a) and afterwards become magnetically (b) or immunospecifically (c) bound at an electrode. Signal either increases due to the presence of alabel (b) or decreases as the redox probe is blocked (c).
Radiation (RT) remains the most frequently used treatment against cancer. The main limitation of RT is its lack of specificity for cancer tissues and the limited maximum radiation dose that can be safely delivered without damaging the surrounding healthy tissues. A step forward in the development of better RT is achieved by coupling it with other treatments, such as photodynamic therapy (PDT). PDT is an anti-cancer therapy that relies on the light activation of non-toxic molecules-called photosensitizers-to generate ROS such as singlet oxygen. By conjugating photosensitizers to dense nanoscintillators in hybrid architectures, the PDT could be activated during RT, leading to cell death through an additional pathway with respect to the one activated by RT alone. Therefore, combining RT and PDT can lead to a synergistic enhancement of the overall efficacy of RT. However, the involvement of hybrids in combination with ionizing radiation is not trivial: the comprehension of the relationship among RT, scintillation emission of the nanoscintillator, and therapeutic effects of the locally excited photosensitizers is desirable to optimize the design of the hybrid nanoparticles for improved effects in radio-oncology. Here, we discuss the working principles of the PDT-activated RT methods, pointing out the guidelines for the development of effective coadjutants to be tested in clinics.
A sensitive and specific approach was developed for the determination of Haemophilus influenza using DNA based bio-assay. In this study, citrate capped silver nanoparticle was synthesized and employed for bioconjugation with pDNA toward target sequences detection. In this study, synthesized probe (SH-5'-AAT TTT CCA ACT TTT TCA CCT GCA T-3') of Haemophilus influenza was detected with great sensitivity and selectivity after hybridization with cDNA (5'-ATG CAG GTG AAA AAG TTG GAA AAT T-3'). Regarding to the obtained results, the low limit of quantification (LLOQ) of DNA sample was 1 ZM using 15 μL of probe and 200 μL of Cit/AgNPs. According to ultra-sensitivity of the fabricated optical DNA-based bio-assay, it has potential for bacterial determination both in clinical and environmental specimens. To evaluate the selectivity of developed DNA based biosensor, three mismatch sequences were applied. Finally, the designed genosensor is a significant diagnostic strategy for detection of Haemophilus influenza with great selectivity.
- MeSH
- biosenzitivní techniky přístrojové vybavení metody MeSH
- biotest MeSH
- DNA bakterií analýza genetika MeSH
- DNA sondy chemie genetika MeSH
- Haemophilus influenzae genetika izolace a purifikace MeSH
- hybridizace nukleových kyselin MeSH
- kovové nanočástice chemie MeSH
- kyselina citronová chemie MeSH
- lidé MeSH
- limita detekce MeSH
- senzitivita a specificita MeSH
- stříbro chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články 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
- MeSH
- aplikace inhalační MeSH
- buněčná imunita * MeSH
- imunotoxiny MeSH
- mitogeny MeSH
- modely nemocí na zvířatech MeSH
- nádory nosu chemicky indukované MeSH
- nádory plic chemicky indukované MeSH
- nanočástice * MeSH
- nikl * imunologie toxicita MeSH
- potkani Sprague-Dawley MeSH
- pracovní expozice MeSH
- proliferace buněk * MeSH
- slezina cytologie MeSH
- techniky in vitro MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
