Iron oxide nanoparticles obtained by the coprecipitation of Fe(II) and Fe(III) salts and oxidation were coated with a novel poly(vinyl acetate-co-5-tert-(butylperoxy)-5-methylhex-1-en-3-yne-co-butyl acrylate-co-maleic anhydride) (PVBM) oligomer to ensure colloidal stability. The magnetic nanoparticles were thoroughly characterized by a range of physico-chemical methods, which proved the presence of the coating on the particles. Experiments with rat mesenchymal stem cells (rMSCs) confirmed that PVBM-coated gamma-Fe2O3 nanoparticles were not cytotoxic and that the average efficiency of stem cell labeling was good and comparable to that obtained with commercial agents. The cells labeled with PVBM-coated gamma-Fe2O3 nanoparticles displayed excellent contrast on magnetic resonance (MR) images. Such particles are thus promising for in vivo MR imaging of transplanted cells. Moreover, PVBM offers the possibility of additional modification by grafting compounds that reduce non-specific protein adsorption.

• MeSH
• barvení a značení metody   MeSH
• femur cytologie   MeSH
• kovové nanočástice chemie   MeSH
• krysa rodu rattus MeSH
• magnetická rezonanční spektroskopie MeSH
• magnetická rezonanční tomografie MeSH
• magnetismus MeSH
• mezenchymální kmenové buňky chemie   MeSH
• molekulární struktura MeSH
• povrchové vlastnosti MeSH
• transmisní elektronová mikroskopie MeSH
• viabilita buněk MeSH
• železité sloučeniny chemie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• fyzikální jevy MeSH
• magnetická rezonanční tomografie MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• radiologie, nukleární medicína a zobrazovací metody
• NLK Publikační typ
• kolektivní monografie

The Cu(II) complexes [Cu(bpdmpz)Cl]ClO4 (1), [Cu(bdmpzp)Cl]ClO4 (2-ClO4), [Cu(bdmpzp)Cl]PF6 (2-PF6) and [Cu(tdmpza)Cl]ClO4 (3), bpdmpzp=[bis[((2-pyridylmethyl)-di(3,5-dimethyl-1H-pyrazolyl)methyl)]amine, bdmpzp=[bis((di(3,5-dimethyl-1H-pyrazolyl)methyl)-(2-pyridylmethyl)]amine and tdmpza=tris[di(3,5-dimethyl-1H-pyrazolyl)-methyl)]amine were synthesized and characterized by elemental analysis, magnetic and conductivity measurements, electrospray-ionization mass spectrometry, infrared and electronic spectroscopy, and X-ray crystallography. The magnetic properties of the complexes, measured at variable temperature, revealed weak antiferromagnetic intermolecular interactions. The cytotoxicity of the complexes 1, 2-ClO4, 3, and 4 ([Cu(bedmpzp)Cl]PF6, where bedmpzp=[bis(3,5-dimethyl-1H-pyrazol-1-yl-1-ethyl)-(2-pyridylmethyl)]amine), was investigated against four human cancer cell lines: A2780 (ovarian), A2780R (cisplatin-resistant variant), HOS (aggressive bone tumors), CaCo2 (epithelial colorectal adenocarcinoma) and on healthy human hepatocytes. The complex 4 was the most cytotoxic one, with IC50=1.4μM (A2780), 8.3μM (A2780R), 4.7μM (HOS) and 10.8μM (CaCo2). The mass spectrometry-based interaction studies, involving selected sulfur-containing biomolecules and small model proteins, revealed pro-oxidant effects of complexes 1 and 4 and differences in stability of both complexes in the mixtures containing the model protein cytochrome c after 24h incubation, complex 1 formed 1:1 adduct, the formation of which was accompanied by the loss of one dimethylpyrazole pendant arm from the bpdmpz ligand, while the complex 4 composition remained intact and the complex formed both 1:1 and 1:2 adducts (cytochrome c vs. Cu(II)-complex).

• MeSH
• aminy chemie   MeSH
• hepatocyty účinky léků   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
• komplexní sloučeniny chemická syntéza   chemie   farmakologie   MeSH
• krystalografie rentgenová MeSH
• kultivované buňky MeSH
• lidé MeSH
• ligandy MeSH
• magnetismus * MeSH
• měď chemie   MeSH
• molekulární struktura MeSH
• nádorové buněčné linie MeSH
• protinádorové látky chemická syntéza   chemie   farmakologie   MeSH
• pyrazoly chemie   MeSH
• screeningové testy protinádorových léčiv MeSH
• spektrofotometrie infračervená MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Custom immuno-magnetic devices are desirable tools for biomedical and biotechnological applications. Herein, surface active maghemite nanoparticles (SAMNs) are proposed as a versatile platform for developing tailored immuno-magnetic nano-carriers by simple wet reactions. Two examples for conjugating native and biotinylated antibodies were presented along with their successful applications in the recognition of specific foodborne pathogens. Nanoparticles were functionalized with rhodamine B isothiocyanate (RITC), leading to a fluorescent nano-conjugate, and used for binding anti-Campylobacter fetus antibodies (SAMN@RITC@Anti-Cf). The microorganism was selectively captured in the presence of two other Campylobacter species (C. jejuni and C. coli), as verified by PCR. Alternatively, SAMNs were modified with avidin, forming a biotin-specific magnetic nano-carrier and used for the immobilization of biotinylated anti-Listeria monocytogenes antibodies (SAMN@avidin@Anti-Lm). This immuno-magnetic carrier was integrated in piezoelectric quartz crystal microbalance (QCM) sensor for the detection of L. monocytogenes in milk, showing a detection limit of 3 bacterial cells. The present work presents a new category of customized immuno-magnetic nano-carriers as a competitive option for suiting specific applications. Graphical abstract ᅟ.

• MeSH
• adjuvancia imunologická chemie   MeSH
• avidin chemie   MeSH
• Listeria imunologie   MeSH
• magnetismus * MeSH
• mikrorovnovážné techniky křemenného krystalu metody   MeSH
• monoklonální protilátky chemie   MeSH
• nanočástice chemie   MeSH
• povrchové vlastnosti MeSH
• transmisní elektronová mikroskopie MeSH
• železité sloučeniny chemie   MeSH
• Publikační typ
• časopisecké články MeSH

Two novel coordination compounds containing heterocyclic bidentate N,N-donor ligand 2-(furan-2-yl)-5-(pyridin-2-yl)-1,3,4-oxadiazole (fpo) were synthesized. A general formula for compounds originating from perchlorates of iron, cobalt, and fpo can be written as: [M(fpo)2(H2O)2](ClO4)2 (M = Fe(II) for (1) Co(II) for (2)). The characterization of compounds was performed by general physico-chemical methods-elemental analysis (EA), Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR) in case of organics, and single crystal X-ray diffraction (sXRD). Moreover, magneto-chemical properties were studied employing measurements in static field (DC) for 1 and X-band EPR (Electron paramagnetic resonance), direct current (DC), and alternating current (AC) magnetic measurements in case of 2. The analysis of DC magnetic properties revealed a high spin arrangement in 1, significant rhombicity for both complexes, and large magnetic anisotropy in 2 (D = -21.2 cm-1). Moreover, 2 showed field-induced slow relaxation of the magnetization (Ueff = 65.3 K). EPR spectroscopy and ab initio calculations (CASSCF/NEVPT2) confirmed the presence of easy axis anisotropy and the importance of the second coordination sphere.

• MeSH
• anizotropie MeSH
• elektronová paramagnetická rezonance MeSH
• furany chemie   MeSH
• kobalt chemie   MeSH
• komplexní sloučeniny chemie   MeSH
• krystalografie rentgenová MeSH
• magnetická rezonanční spektroskopie MeSH
• molekulární modely MeSH
• oxadiazoly chemie   MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• spektroskopie Mossbauerova MeSH
• železnaté sloučeniny chemie   MeSH
• železo chemie   MeSH
• Publikační typ
• časopisecké články MeSH

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.

• MeSH
• antioxidancia farmakologie   MeSH
• cer * MeSH
• magnetické nanočástice * MeSH
• nanočástice * MeSH
• tkáňová distribuce MeSH
• železité sloučeniny MeSH
• Publikační typ
• časopisecké články MeSH

Magnetite (Fe3O4) nanoparticles with uniform sizes of 10, 20, and 31 nm were prepared by thermal decomposition of Fe(III) oleate or mandelate in a high-boiling point solvent (>320 °C). To render the particles with hydrophilic and antifouling properties, their surface was coated with a PEG-containing bisphosphonate anchoring group. The PEGylated particles were characterized by a range of physicochemical methods, including dynamic light scattering, transmission electron microscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy, and magnetization measurements. As the particle size increased from 10 to 31 nm, the amount of PEG coating decreased from 28.5 to 9 wt.%. The PEG formed a dense brush-like shell on the particle surface, which prevented particles from aggregating in water and PBS (pH 7.4) and maximized the circulation time in vivo. Magnetic resonance relaxometry confirmed that the PEG-modified Fe3O4 nanoparticles had high relaxivity, which increased with increasing particle size. In the in vivo experiments in a mouse model, the particles provided visible contrast enhancement in the magnetic resonance images. Almost 70% of administrated 20-nm magnetic nanoparticles still circulated in the blood stream after four hours; however, their retention in the tumor was rather low, which was likely due to the antifouling properties of PEG.

• MeSH
• bisfosfonáty chemie   MeSH
• magnetická rezonanční tomografie MeSH
• magnetické nanočástice chemie   ultrastruktura   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• polyethylenglykoly chemie   MeSH
• tkáňová distribuce MeSH
• transmisní elektronová mikroskopie MeSH
• velikost částic MeSH
• železité sloučeniny MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

A series of rhodanine derivatives was prepared. The synthetic approach, analytical and spectroscopic data of all synthesized compounds are presented. Lipophilicity of all the discussed rhodanine derivatives was analyzed using the RP-HPLC method. The compounds were tested for their ability to inhibit photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts and reduce chlorophyll content in freshwater alga Chlorella vulgaris. Structure-activity relationships between the chemical structure, physical properties and biological activities of the evaluated compounds are discussed. For majority of the tested compounds the lipophilicity of the compound and not electronic properties of the R1 substituent were decisive for PET-inhibiting activity. The most potent PET inhibitor was (5Z)-5-(4-bromobenzylidene)-2-thioxo-1,3-thiazolidin-4-one (IC(50) = 3.0 μmol/L) and the highest antialgal activity was exhibited by (5Z)-5-(4-chlorobenzylidene)-2-thioxo-1,3-thiazolidin-4-one (IC(50) = 1.3 μmol/L).

• MeSH
• Chlorella vulgaris účinky léků   metabolismus   MeSH
• chloroplasty účinky léků   metabolismus   MeSH
• fotosyntéza účinky léků   MeSH
• hydrofobní a hydrofilní interakce MeSH
• nukleární magnetická rezonance biomolekulární MeSH
• rhodanin analogy a deriváty   chemická syntéza   farmakologie   MeSH
• Spinacia oleracea účinky léků   metabolismus   MeSH
• transport elektronů účinky léků   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Nearly monodispersed superparamagnetic maghemite nanoparticles (15-20nm) were prepared by a one-step thermal decomposition of iron(II) acetate in air at 400 degrees C. The presented synthetic route is simple, cost effective and allows to prepare the high-quality superparamagnetic particles in a large scale. The as-prepared particles were exploited for the development of magnetic nanocomposites with the possible applicability in medicine and biochemistry. For the purposes of the MRI diagnostics, the maghemite particles were simply dispersed in the bentonite matrix. The resulting nanocomposite represents very effective and cheap oral negative contrast agent for MRI of the gastrointestinal tract and reveals excellent contrast properties, fully comparable with those obtained for commercial contrast material. The results of the clinical research of this maghemite-bentonite contrast agent for imaging of the small bowel are discussed. For biochemical applications, the primary functionalization of the prepared maghemite nanoparticles with chitosan was performed. In this way, a highly efficient magnetic carrier for protein immobilization was obtained as demonstrated by conjugating thermostable raffinose-modified trypsin (RMT) using glutaraldehyde. The covalent conjugation resulted in a further increase in trypsin thermostability (T(50)=61 degrees C) and elimination of its autolysis. Consequently, the immobilization of RMT allowed fast in-solution digestion of proteins and their identification by MALDI-TOF mass spectrometry.

• MeSH
• difrakce rentgenového záření MeSH
• enzymy imobilizované MeSH
• financování organizované MeSH
• gastrointestinální trakt patologie   MeSH
• kontrastní látky MeSH
• magnetická rezonanční tomografie MeSH
• mikroskopie elektronová rastrovací MeSH
• transmisní elektronová mikroskopie MeSH
• trypsin MeSH
• železité sloučeniny MeSH

Magnetic polymer nanocomposites are inherently multifunctional and harbor assorted physiochemical actions for applications thereof as novel drug nanocarriers. Herein, Fe3O4-nanoparticles were supported on rice straw cellulose for 5-fluorouracil carrier abbreviated as MC/5-FU for potential colorectal cancer treatments. Several analyses indicated the multifunctional properties of MC/5-FU bionanocomposites. Transmission and scanning electron microscopy study demonstrated that Fe3O4 nanofillers covered the cellulose matrix. The drug release from MC/5-FU was evaluated under various pH and temperature conditions, showing the maximum release at pH 7.4 and 44.2 °C. In in vitro anticancer assay, MC/5-FU exhibited enhanced selectivity and anticancer actions against 2D monolayer and 3D tumour spheroid models colorectal cancer cells. The anticancer effects of MC/5-FU with magnetic targeting and heat induction were also examined. This easily synthesized MC/5-FU indicated the potential in application as a low-cost drug formulation for colorectal cancer treatments.

• MeSH
• buňky HT-29 MeSH
• celulosa chemie   MeSH
• fluoruracil chemie   farmakologie   MeSH
• HCT116 buňky MeSH
• kolorektální nádory farmakoterapie   metabolismus   MeSH
• lékové transportní systémy metody   MeSH
• lidé MeSH
• magnetické jevy MeSH
• magnetické nanočástice oxidů železa chemie   MeSH
• mikroskopie elektronová rastrovací metody   MeSH
• nanokompozity chemie   MeSH
• nosiče léků chemie   MeSH
• polymery chemie   MeSH
• protinádorové látky farmakologie   MeSH
• uvolňování léčiv MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH