Gold nanoshells with magnetic cores and a urea-based receptor for SERS sensing of fluoride anions: experimental and computational study.

The study demonstrates that a combination of plasmonic nanostructures and artificial receptors can be applied for sensing small molecular species. Gold nanoshells containing magnetic cores are used as the SERS-active substrates, which opens the way for the development of multimodal contrast agents with applicability extended to sensing or for the separation of analytes by magnetic solid-phase extraction. Disubstituted ureas forming hydrogen-bonded complexes with certain anions can be employed as molecular sensors. In this case study, gold nanoshells with silica-coated Mn-Zn ferrite cores were prepared by a multistep procedure. The nanoshells were co-functionalized with an N-(4-mercaptophenyl)-N'-(4-nitrophenyl)urea sensor synthesized directly on the gold surface, and with 4-nitrothiophenol, which is adopted as an internal standard. SERS measurements were carried out with acetonitrile solutions of tetrabutylammonium fluoride (Bu4NF) over a concentration range of 10-10-10-1 mol L-1. The spectral response of the sensor is dependent on the fluoride concentration in the range of 10-5-10-1 mol L-1. To investigate further the SERS mechanism, a model sensor, N-(4-bromophenyl)-N'-(4-nitrophenyl)urea, was synthesized and used in Raman spectroscopy with solutions of Bu4NF, up to a molar ratio of 1 : 20. The spectra and the interactions between the sensors and fluoride anions were also studied by extensive DFT computations.

Multimodal Contrast Agent Enabling pH Sensing Based on Organically Functionalized Gold Nanoshells with Mn-Zn Ferrite Cores.

Highly complex nanoparticles combining multimodal imaging with the sensing of physical properties in biological systems can considerably enhance biomedical research, but reports demonstrating the performance of a single nanosized probe in several imaging modalities and its sensing potential at the same time are rather scarce. Gold nanoshells with magnetic cores and complex organic functionalization may offer an efficient multimodal platform for magnetic resonance imaging (MRI), photoacoustic imaging (PAI), and fluorescence techniques combined with pH sensing by means of surface-enhanced Raman spectroscopy (SERS). In the present study, the synthesis of gold nanoshells with Mn-Zn ferrite cores is described, and their structure, composition, and fundamental properties are analyzed by powder X-ray diffraction, X-ray fluorescence spectroscopy, transmission electron microscopy, magnetic measurements, and UV-Vis spectroscopy. The gold surface is functionalized with four different model molecules, namely thioglycerol, meso-2,3-dimercaptosuccinate, 11-mercaptoundecanoate, and (11-mercaptoundecyl)-N,N,N-trimethylammonium bromide, to analyze the effect of varying charge and surface chemistry on cells in vitro. After characterization by dynamic and electrophoretic light scattering measurements, it is found that the particles do not exhibit significant cytotoxic effects, irrespective of the surface functionalization. Finally, the gold nanoshells are functionalized with a combination of 4-mercaptobenzoic acid and 7-mercapto-4-methylcoumarin, which introduces a SERS active pH sensor and a covalently attached fluorescent tag at the same time. 1H NMR relaxometry, fluorescence spectroscopy, and PAI demonstrate the multimodal potential of the suggested probe, including extraordinarily high transverse relaxivity, while the SERS study evidences a pH-dependent spectral response.

Multimodal fluorescently labeled polymer-coated GdF3 nanoparticles inhibit degranulation in mast cells.

Multimodal gadolinium fluoride nanoparticles belong to potential contrast agents useful for bimodal optical fluorescence and magnetic resonance imaging. However, the metallic nature of the nanoparticles, similarly to some paramagnetic iron oxides, might induce allergic and anaphylactic reactions in patients after administration. A reduction of these adverse side effects is a priority for the safe application of the nanoparticles. Herein, we prepared paramagnetic poly(4-styrenesulfonic acid-co-maleic acid) (PSSMA)-stabilized GdF3 nanoparticles with surface modified by Atto 488-labeled poly(styrene-grad-2-dimethylaminoethyl acrylate)-block-poly(2-dimethylaminoethyl acrylate) (PSDA-A488) with reactive amino groups for introduction of an additional imaging (luminescence) modality and possible targeting of anticancer drugs. The saturation magnetization of GdF3@PSSMA particles according to SQUID magnetometry reached 157 Am2 kg-1 at 2 K and magnetic field of 7 T. GdF3@PSSMA-PSDA-A488 nanoparticles were well tolerated by human cervical adenocarcinoma (HeLa), mouse bone marrow-derived mast cells (BMMC), and rat basophilic mast cells (RBL-2H3); the particles also affected cell morphology and protein tyrosine phosphorylation in mast cells. Moreover, the nanoparticles interfered with the activation of mast cells by multivalent antigens and inhibited calcium mobilization and cell degranulation. These findings show that the new multimodal GdF3-based nanoparticles possess properties useful for various imaging methods and might minimize mast cell degranulation incurred after future nanoparticle diagnostic administration.

Modelling and Measurement of Magnetically Soft Nanowire Arrays for Sensor Applications.

Soft magnetic wires and microwires are currently used for the cores of magnetic sensors. Due to their low demagnetization, they contribute to the high sensitivity and the high spatial resolution of fluxgates, Giant Magnetoimpedance (GMI), and inductive sensors. The arrays of nanowires can be prepared by electrodeposition into predefined pores of a nanoporous polycarbonate membrane. While high coercivity arrays with square loops are convenient for information storage and for bistable sensors such as proximity switches, low coercivity cores are needed for linear sensors. We show that coercivity can be controlled by the geometry of the array: increasing the diameter of nanowires (20 µm in length) from 30 nm to 200 nm reduced the coercivity by a factor of 10, while the corresponding decrease in the apparent permeability was only 5-fold. Finite element simulation of nanowire arrays is important for sensor development, but it is computationally demanding. While an array of 2000 wires can be still modelled in 3D, this is impossible for real arrays containing millions of wires. We have developed an equivalent 2D model, which allows us to solve these large arrays with acceptable accuracy. Using this tool, we have shown that as a core of magnetic sensors, nanowires are efficiently employed only together with microcoils with diameter comparable to the nanowire length.

Spatial covariance of herbivorous and predatory guilds of forest canopy arthropods along a latitudinal gradient.

In arthropod community ecology, species richness studies tend to be prioritised over those investigating patterns of abundance. Consequently, the biotic and abiotic drivers of arboreal arthropod abundance are still relatively poorly known. In this cross-continental study, we employ a theoretical framework in order to examine patterns of covariance among herbivorous and predatory arthropod guilds. Leaf-chewing and leaf-mining herbivores, and predatory ants and spiders, were censused on > 1000 trees in nine 0.1 ha forest plots. After controlling for tree size and season, we found no negative pairwise correlations between guild abundances per plot, suggestive of weak signals of both inter-guild competition and top-down regulation of herbivores by predators. Inter-guild interaction strengths did not vary with mean annual temperature, thus opposing the hypothesis that biotic interactions intensify towards the equator. We find evidence for the bottom-up limitation of arthropod abundances via resources and abiotic factors, rather than for competition and predation.

Broadband dielectric spectroscopy of La0.65Sr0.35MnO3@TiO2 core-shell nanocomposites.

Core-shell composites of ferromagnetic conducting nanoparticles La0.65Sr0.35MnO3 (LSMO) embedded in an insulating matrix of TiO2 (LSMO@TiO2) have been processed, structurally and magnetically characterized, and their DC magnetoresistivity and complex dielectric response measured and fitted from Hz up to the infrared (IR) range (1014 Hz). XRD indicates that the TiO2 shells are amorphous. Modelling of the IR spectra using standard models based on the effective medium approximation has it confirmed and has characterized the effective phonon modes of the LSMO nanoceramics and LSMO@TiO2 composite. Modelling of the lower-frequency spectra has shown that TiO2 shell thicknesses are rather non-uniform down to thin nm values, which leads to giant low-frequency permittivity values and non-negligible free-carrier tunnelling among the LSMO cores. Two main dielectric dispersion regions were observed and shown to be due to the inhomogeneous conductivity-the one occuring in the 1011-1012 Hz range relates to nonmagnetic less-conducting dead layers on the surface of LSMO nanocrystallites and the broad second one below the 1010 Hz range is due to the non-uniform thicknesses of the dielectric TiO2 shells. In the IR range, effective phonon modes of the LSMO nanoceramics and LSMO@TiO2 composite were characterized from the reflectivity spectra.

Magnetic nanoparticles of Ga-substituted ε-Fe2 O3 for biomedical applications: Magnetic properties, transverse relaxivity, and effects of silica-coated particles on cytoskeletal networks.

Magnetic nanoparticles of ε-Fe1.76 Ga0.24 O3 with the volume-weighted mean size of 17 nm were prepared by thermal treatment of a mesoporous silica template impregnated with metal nitrates and were coated with silica shell of four different thicknesses in the range 6-24 nm. The bare particles exhibited higher magnetization than the undoped compound, 22.4 Am2 kg-1 at 300 K, and were characterized by blocked state with the coercivity of 1.2 T at 300 K, being thus the very opposite of superparamagnetic iron oxides. The relaxometric study of the silica-coated samples at 0.47 T revealed promising properties for MRI, specifically, transverse relaxivity of 89-168 s-1 mmol(f.u.)-1 L depending on the shell thickness was observed. We investigated the effects of the silica-coated nanoparticles on human A549 and MCF-7 cells. Cell viability, proliferation, cell cycle distribution, and the arrangement of actin cytoskeleton were assessed, as well as formation and maturation of focal adhesions. Our study revealed that high concentrations of silica-coated particles with larger shell thicknesses of 16-24 nm interfere with the actin cytoskeletal networks, inducing thus morphological changes. Consequently, the focal adhesion areas were significantly decreased, resulting in impaired cell adhesion.

Synthesis and characterization of Au nanoshells with a magnetic core and betaine derivatives.

The article describes preparation, characterization and further modification of hybrid magnetic particles (Au nanoshells with a magnetic core (MPs@silica@Au)) by zwitterionic molecules bearing diazonium functional groups. Such hybrid magnetic particles modified by zwitterionic molecules exhibit the following features: •Responsiveness towards external magnetic field applicable for various enrichment strategies due to magnetic core;•Golden outer layer exhibiting free surface plasmons could be used for grafting of zwitterionic molecules via diazonium functionality;•Zwitterionic interface on such particles provides resistivity towards non-specific protein binding; and at the same time such interface was applied for immobilization of antibodies against prostate specific antigen (PSA) applied for selective enrichment of PSA from serum samples with subsequent electrochemical assays. The approach presented here using hybrid magnetic particles can be easily applied for immobilization of antibodies using a highly robust surface patterning protocols i.e. by formation of a self-assembled monolayer with delivery of functional groups on the outer surface of magnetic particles. Hybrid magnetic particles with immobilized antibodies are applied for highly efficient and quick separation of protein of interest i.e. PSA from complex sample. Finally, hybrid magnetic particles with "fished-out" protein molecules could be incubated with lectins to form a sandwich configuration for glycoprofiling of PSA.

Quantitative assessment of plant-arthropod interactions in forest canopies: A plot-based approach.

Research on canopy arthropods has progressed from species inventories to the study of their interactions and networks, enhancing our understanding of how hyper-diverse communities are maintained. Previous studies often focused on sampling individual tree species, individual trees or their parts. We argue that such selective sampling is not ideal when analyzing interaction network structure, and may lead to erroneous conclusions. We developed practical and reproducible sampling guidelines for the plot-based analysis of arthropod interaction networks in forest canopies. Our sampling protocol focused on insect herbivores (leaf-chewing insect larvae, miners and gallers) and non-flying invertebrate predators (spiders and ants). We quantitatively sampled the focal arthropods from felled trees, or from trees accessed by canopy cranes or cherry pickers in 53 0.1 ha forest plots in five biogeographic regions, comprising 6,280 trees in total. All three methods required a similar sampling effort and provided good foliage accessibility. Furthermore, we compared interaction networks derived from plot-based data to interaction networks derived from simulated non-plot-based data focusing either on common tree species or a representative selection of tree families. All types of non-plot-based data showed highly biased network structure towards higher connectance, higher web asymmetry, and higher nestedness temperature when compared with plot-based data. Furthermore, some types of non-plot-based data showed biased diversity of the associated herbivore species and specificity of their interactions. Plot-based sampling thus appears to be the most rigorous approach for reconstructing realistic, quantitative plant-arthropod interaction networks that are comparable across sites and regions. Studies of plant interactions have greatly benefited from a plot-based approach and we argue that studies of arthropod interactions would benefit in the same way. We conclude that plot-based studies on canopy arthropods would yield important insights into the processes of interaction network assembly and dynamics, which could be maximised via a coordinated network of plot-based study sites.

Advanced impedimetric biosensor configuration and assay protocol for glycoprofiling of a prostate oncomarker using Au nanoshells with a magnetic core.

In this paper several advances were implemented for glycoprofiling of prostate specific antigen (PSA), what can be applied for better prostate cancer (PCa) diagnostics in the future: 1) application of Au nanoshells with a magnetic core (MP@silica@Au); 2) use of surface plasmons of Au nanoshells with a magnetic core for spontaneous immobilization of zwitterionic molecules via diazonium salt grafting; 3) a double anti-fouling strategy with integration of zwitterionic molecules on Au surface and on MP@silica@Au particles was implemented to resist non-specific protein binding; 4) application of anti-PSA antibody modified Au nanoshells with a magnetic core for enrichment of PSA from a complex matrix of a human serum; 5) direct incubation of anti-PSA modified MP@silica@Au with affinity bound PSA to the lectin modified electrode surface. The electrochemical impedance spectroscopy (EIS) signal was enhanced 43 times integrating Au nanoshells with a magnetic core compared to the biosensor without them. This proof-of-concept study shows that the biosensor could detect PSA down to 1.2 fM and at the same time to glycoprofile such low PSA concentration using a lectin patterned biosensor device. The biosensor offers a recovery index of 108%, when serum sample was spiked with a physiological concentration of PSA (3.5 ng mL-1).

Manganese-Zinc Ferrites: Safe and Efficient Nanolabels for Cell Imaging and Tracking In Vivo.

Manganese-zinc ferrite nanoparticles were synthesized by using a hydrothermal treatment, coated with silica, and then tested as efficient cellular labels for cell tracking, using magnetic resonance imaging (MRI) in vivo. A toxicity study was performed on rat mesenchymal stem cells and C6 glioblastoma cells. Adverse effects on viability and cell proliferation were observed at the highest concentration (0.55 mM) only; cell viability was not compromised at lower concentrations. Nanoparticle internalization was confirmed by transmission electron microscopy. The particles were found in membranous vesicles inside the cytoplasm. Although the metal content (0.42 pg Fe/cell) was lower compared to commercially available iron oxide nanoparticles, labeled cells reached a comparable relaxation rate R 2, owing to higher nanoparticle relaxivity. Cells from transgenic luciferase-positive rats were used for in vivo experiments. Labeled cells were transplanted into the muscles of non-bioluminescent rats and visualized by MRI. The cells produced a distinct hypointense signal in T2- or T2*-weighted MR images in vivo. Cell viability in vivo was verified by bioluminescence.

Multimodal PSSMA-Functionalized GdF3 : Eu3+ (Tb3+ ) Nanoparticles for Luminescence Imaging, MRI, and X-Ray Computed Tomography.

Biocompatible poly(4-styrenesulfonic acid-co-maleic acid)-stabilized GdF3 : Eu3+ (Tb3+ ) nanoparticles were obtained by a one-step coprecipitation method in ethylene glycol or water. The particles are very small (3 nm), have a narrow size distribution, and were detectable by fluorescence, magnetic resonance, and X-ray contrast imaging. These properties allow multimodal imaging, which has prospective applications in the simultaneous and detailed detection of diseased tissues.

Phylogenetic composition of host plant communities drives plant-herbivore food web structure.

Insects tend to feed on related hosts. The phylogenetic composition of host plant communities thus plays a prominent role in determining insect specialization, food web structure, and diversity. Previous studies showed a high preference of insect herbivores for congeneric and confamilial hosts suggesting that some levels of host plant relationships may play more prominent role that others. We aim to quantify the effects of host phylogeny on the structure of quantitative plant-herbivore food webs. Further, we identify specific patterns in three insect guilds with different life histories and discuss the role of host plant phylogeny in maintaining their diversity. We studied herbivore assemblages in three temperate forests in Japan and the Czech Republic. Sampling from a canopy crane, a cherry picker and felled trees allowed a complete census of plant-herbivore interactions within three 0·1 ha plots for leaf chewing larvae, miners, and gallers. We analyzed the effects of host phylogeny by comparing the observed food webs with randomized models of host selection. Larval leaf chewers exhibited high generality at all three sites, whereas gallers and miners were almost exclusively monophagous. Leaf chewer generality dropped rapidly when older host lineages (5-80 myr) were collated into a single lineage but only decreased slightly when the most closely related congeneric hosts were collated. This shows that leaf chewer generality has been maintained by feeding on confamilial hosts while only a few herbivores were shared between more distant plant lineages and, surprisingly, between some congeneric hosts. In contrast, miner and galler generality was maintained mainly by the terminal nodes of the host phylogeny and dropped immediately after collating congeneric hosts into single lineages. We show that not all levels of host plant phylogeny are equal in their effect on structuring plant-herbivore food webs. In the case of generalist guilds, it is the phylogeny of deeper plant lineages that drives the food web structure whereas the terminal relationships play minor roles. In contrast, the specialization and abundance of monophagous guilds are affected mainly by the terminal parts of the plant phylogeny and do not generally reflect deeper host phylogeny.

Magnetic properties of rare-earth-doped La0.7Sr0.3MnO3.

Rare-earth-doped ferromagnetic manganites La0.63RE0.07Sr0.30MnO3 (RE = Gd, Tb, Dy, and Ho) are synthesized in the form of sintered ceramics and nanocrystalline phases with the mean size of crystallites ≈30 nm. The electronic states of the dopants are investigated by SQUID magnetometry and theoretically interpreted based on the calculations of the crystal field splitting of rare-earth energy levels. The samples show the orthorhombic perovskite structure of Ibmm symmetry, with a complete FM order of Mn spins in bulk and reduced order in nanoparticles. Non-zero moments are also detected at the perovskite A sites, which can be attributed to magnetic polarization of the rare-earth dopants. The measurements in external field up to 70 kOe show a standard Curie-type contribution of the spin-only moments of Gd3+ ions, whereas Kramers ions Dy3+ and non-Kramers ions Ho3+ contribute by Ising moments due to their doublet ground states. The behaviour of non-Kramers ions Tb3+ is anomalous, pointing to singlet ground state with giant Van Vleck paramagnetism. The Tb3+ doping leads also to a notably increased coercivity compared to other La0.63RE0.07Sr0.30MnO3 systems.

Effects of Tb(3+) dopants in the La1-x Sr x MnO3 bulk and nanoparticle ferromagnets.

Three forms of La,Sr-manganites are synthesized and the role of Tb doping is investigated. First two systems are sol-gel nanoparticles and sintered ceramics of the composition La0.56Tb0.07Sr0.37MnO3, whereas the third system is formed by comparable nanoparticles La0.51Tb0.06Sr0.43MnO3 synthesized in molten salt. The samples show pseudocubic perovskite structure with only small tilts of MnO6 that point to Ibmm symmetry in the bulk and [Formula: see text] symmetry in nanoparticles. SQUID magnetometry and neutron diffraction reveal a complete FM order of Mn spins in bulk, a reduced order in nanoparticles, and non-zero moments at A sites. Detailed analysis suggests that the dodecahedral coordination of A sites adapts to small terbium size, and the resulting crystal field splitting of Tb(3+) yields a singlet ground state. The response to exchange and external fields is characterized as a giant Van Vleck paramagnetism in contrast to the Curie-type behaviour of Tb-based orthoaluminates and orthocobaltites with the quasi-doublet ground state.

Fluorescent magnetic nanoparticles for cell labeling: flux synthesis of manganite particles and novel functionalization of silica shell.

Novel synthetic approaches for the development of multimodal imaging agents with high chemical stability are demonstrated. The magnetic cores are based on La0.63Sr0.37MnO3 manganite prepared as individual grains using a flux method followed by additional thermal treatment in a protective silica shell allowing to enhance their magnetic properties. The cores are then isolated and covered de novo with a hybrid silica layer formed through the hydrolysis and polycondensation of tetraethoxysilane and a fluorescent silane synthesized from rhodamine, piperazine spacer, and 3-iodopropyltrimethoxysilane. The aminoalkyltrialkoxysilanes are strictly avoided and the resulting particles are hydrolytically stable and do not release dye. The high colloidal stability of the material and the long durability of the fluorescence are reinforced by an additional silica layer on the surface of the particles. Structural and magnetic studies of the products using XRD, TEM, and SQUID magnetometry confirm the importance of the thermal treatment and demonstrate that no mechanical treatment is required for the flux-synthesized manganite. Detailed cell viability tests show negligible or very low toxicity at concentrations at which excellent labeling is achieved. Predominant localization of nanoparticles in lysosomes is confirmed by immunofluorescence staining. Relaxometric and biological studies suggest that the functionalized nanoparticles are suitable for imaging applications.

The global distribution of diet breadth in insect herbivores.

Understanding variation in resource specialization is important for progress on issues that include coevolution, community assembly, ecosystem processes, and the latitudinal gradient of species richness. Herbivorous insects are useful models for studying resource specialization, and the interaction between plants and herbivorous insects is one of the most common and consequential ecological associations on the planet. However, uncertainty persists regarding fundamental features of herbivore diet breadth, including its relationship to latitude and plant species richness. Here, we use a global dataset to investigate host range for over 7,500 insect herbivore species covering a wide taxonomic breadth and interacting with more than 2,000 species of plants in 165 families. We ask whether relatively specialized and generalized herbivores represent a dichotomy rather than a continuum from few to many host families and species attacked and whether diet breadth changes with increasing plant species richness toward the tropics. Across geographic regions and taxonomic subsets of the data, we find that the distribution of diet breadth is fit well by a discrete, truncated Pareto power law characterized by the predominance of specialized herbivores and a long, thin tail of more generalized species. Both the taxonomic and phylogenetic distributions of diet breadth shift globally with latitude, consistent with a higher frequency of specialized insects in tropical regions. We also find that more diverse lineages of plants support assemblages of relatively more specialized herbivores and that the global distribution of plant diversity contributes to but does not fully explain the latitudinal gradient in insect herbivore specialization.

Gadolinium- and manganite-based contrast agents with fluorescent probes for both magnetic resonance and fluorescence imaging of pancreatic islets: a comparative study.

Three magnetic resonance (MR)/fluorescence imaging probes were tested for visualization, cellular distribution, and survival of labeled pancreatic islets in vitro and following transplantation. As T(1) contrast agents (CAs), gadolinium(III) complexes linked to ß-cyclodextrin (Gd-F-ßCD) or bound to titanium dioxide (TiO2 @RhdGd) were tested. As a T(2) CA, perovskite manganite nanoparticles (LSMO@siF@si) were examined. Fluorescein or rhodamine was incorporated as a fluorescent marker in all probes. Islets labeled with gadolinium(III) CAs were visible as hyperintense spots on MR in vitro, but detection in vivo was inconclusive. Islets labeled with LSMO@siF@si CA were clearly visible as hypointense spots or areas on MR scans in vitro as well as in vivo. All CAs were detected inside the islet cells by fluorescence. Although the vitality and function of the labeled islets was not impaired by any of the tested CAs, results indicate that LSMO@siF@si CA is a superior marker for islet labeling, as it provides better contrast enhancement within a shorter scan time.

Anilinium dihydrogen phosphate.

The triclinic structure of the title compound, C(6)H(8)N(+)·H(2)PO(4)(-), with three symmetry-independent structural units (Z' = 3), is formed of separate organic and inorganic layers alternating along the b axis. The building blocks of the inorganic layer are deformed H(2)PO(4) tetrahedra assembled into infinite ladders by short and hence strong hydrogen bonds. The anilinium cations forming the organic layer are not hydrogen bonded to one another, but they are anchored by four N-H···O crosslinks between the dihydrogen phosphate chains of adjacent ladders. Two H atoms of each -NH(3) group then form one normal and one bifurcated N-H···O hydrogen bond to the P=O oxygens of two tetrahedra of one chain, while the third H atom is hydrogen bonded to the nearest O atom of an adjacent chain belonging to another dihydrogen phosphate ladder.

Silica-coated La0.75Sr0.25MnO3 nanoparticles for magnetically driven DNA isolation.

Magnetic La(0.75)Sr(0.25)MnO(3) nanoparticles possessing an approximately 20-nm-thick silica shell (LSMO(0.25)@SiO(2) ) were characterised and tested for the isolation of PCR-ready bacterial DNA. The results presented here show that the nanoparticles do not interfere in PCR. DNA was apparently reversibly adsorbed on their silica shell from the aqueous phase system (16% PEG 6000-2 M NaCl). The method proposed was used for DNA isolation from complex food samples (dairy products and probiotic food supplements). The isolated DNA was compatible with PCR. The main advantages of the nanoparticles tested for routine use were their high colloidal stability allowing a more precise dosage and therefore high reproducibility of DNA isolation.