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Bifunctional and highly uniform Ln:BaGdF5 (Ln = Eu(3+) and Nd(3+)) nanoparticles have been successfully synthesized using a solvothermal method consisting of the aging at 120 °C of a glycerol solution containing the corresponding... more
Bifunctional and highly uniform Ln:BaGdF5 (Ln = Eu(3+) and Nd(3+)) nanoparticles have been successfully synthesized using a solvothermal method consisting of the aging at 120 °C of a glycerol solution containing the corresponding Lanthanide acetylacetonates and butylmethylimidazolium tetrafluoroborate. The absence of any surfactant in the synthesis process rendered hydrophilic nanospheres (with tunable diameter from 45 nm 85 nm, depending on the cations concentration of the starting solution) which are suitable for bioapplications. The particles are bifunctional because they showed both optical and magnetic properties due to the presence of the optically active lanthanides (Eu(3+) in the visible and Nd(3+) in the NIR regions of the electromagnetic spectrum) and the paramagnetic gadolinium ion, respectively. The luminescence decay curves of the nanospheres doped with different amounts of Eu(3+) and Nd(3+) have been recorded in order to determine the optimum dopant concentration in ea...
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Research Interests: Chemical Engineering, Materials Science, Nanoparticle, Quality Improvement, Drug delivery, and 13 moreNanotechnology, Molecular Imaging, Iron Oxide, Iron, Protein Interaction, Active site, Size Distribution, Superparamagnetism, Thermal Decomposition, Oleic Acid, Protein Binding, Particle Size Distribution, and Relaxation Time
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Aim: To investigate the influence of gold nanoparticle geometry on the biochemical response of Calu-3 epithelial cells. Materials & methods: Spherical, triangular and hexagonal gold nanoparticles (GNPs) were used. The GNP-cell interaction... more
Aim: To investigate the influence of gold nanoparticle geometry on the biochemical response of Calu-3 epithelial cells. Materials & methods: Spherical, triangular and hexagonal gold nanoparticles (GNPs) were used. The GNP-cell interaction was assessed via atomic absorption spectroscopy (AAS) and transmission electron microscopy (TEM). The biochemical impact of GNPs was determined over 72 h at (0.0001–1 mg/ml). Results: At 1 mg/ml, hexagonal GNPs reduced Calu-3 viability below 60%, showed increased reactive oxygen species production and higher expression of proapoptotic markers. A cell mass burden of 1:2:12 as well as number of GNPs per cell (2:1:3) was observed for spherical:triangular:hexagonal GNPs. Conclusion: These findings do not suggest a direct shape-toxicity effect. However, do highlight the contribution of shape towards the GNP-cell interaction which impacts upon their intracellular number, mass and volume dose.
Research Interests: Materials Science, Chemistry, Nanobiotechnology, Apoptosis, Medicine, and 15 moreMetal Nanoparticles, Caspases, Biocompatibility, Humans, Gold, Medical Biotechnology, Gold Nanoparticles, Cell Death, Drug Delivery Systems, Caspase, Epithelial cells, Cell Survival, Colloidal Gold, Intracellular, and lung epithelial cells
Aims: RNAi is a powerful tool for gene silencing that can be used to reduce undesirable overexpression of oncogenes as a novel form of cancer treatment. However, when using RNAi as a therapeutic tool there is potential for associated gene... more
Aims: RNAi is a powerful tool for gene silencing that can be used to reduce undesirable overexpression of oncogenes as a novel form of cancer treatment. However, when using RNAi as a therapeutic tool there is potential for associated gene effects. This study aimed to utilize gold nanoparticles to deliver siRNA into HeLa cells. Results: Knockdown of the c-myc oncogene by RNAi, at the RNA, protein and cell proliferation level was achieved, while also identifying associated gene responses. Discussion: The gold nanoparticles used in this study present an excellent delivery platform for siRNA, but do note associated gene changes. Conclusion: The study highlights the need to more widely assess the cell physiological response to RNAi treatment, rather than focus on the immediate RNA levels.
Research Interests: Nanomaterials Characterization, Biology, Nanobiotechnology, Cell Cycle, Nanocomposites, and 15 moreNanomedicine, Nanomaterials, Nanoparticles, Nanotechnology, Apoptosis, Medicine, Gene Silencing, Metal Nanoparticles, Humans, Gold, Medical Biotechnology, Gold Nanoparticles, Nanoscience, HeLa cells, and HeLa
Here we have investigated the effect of enshrouding polymer-coated nanoparticles (NPs) with polyethylene glycol (PEG) on the adsorption of proteins and uptake by cultured cells. PEG was covalently linked to the polymer surface to the... more
Here we have investigated the effect of enshrouding polymer-coated nanoparticles (NPs) with polyethylene glycol (PEG) on the adsorption of proteins and uptake by cultured cells. PEG was covalently linked to the polymer surface to the maximal grafting density achievable under our experimental conditions. Changes in the effective hydrodynamic radius of the NPs upon adsorption of human serum albumin (HSA) and fibrinogen (FIB) were measured in situ by using fluorescence correlation spectroscopy (FCS). For NPs without a PEG shell, a thickness increase of around 3 nm, corresponding to HSA monolayer adsorption, was measured at high HSA concentration. Only 50% of this value was found for NPs with PEGylated surfaces. While the size increase clearly reveals formation of a protein corona also for PEGylated NPs, fluorescence lifetime measurements and quenching experiments suggest that the adsorbed HSA molecules are buried within the PEG shell. For FIB adsorption onto PEGylated NPs, even less ch...
Research Interests: Materials Science, Nanoparticle, Nanoparticles, Medicine, Multidisciplinary, and 15 moreAdsorption, Fluorescence Correlation Spectroscopy, Fibrinogen, Humans, Mice, Animals, T cells, Polyethylene Glycol, Amino Acid Sequence, Protein Corona, Polyethylene Glycols, Molecular Sequence Data, fibroblasts, Human serum albumin, and Polymer coating
Aim: To assess the cell response to magnetic nanoparticles under an alternating magnetic field by molecular quantification of heat responsive transcripts in two model systems. Materials & methods: Melanoma cells and Hydra vulgaris treated... more
Aim: To assess the cell response to magnetic nanoparticles under an alternating magnetic field by molecular quantification of heat responsive transcripts in two model systems. Materials & methods: Melanoma cells and Hydra vulgaris treated with magnetic nanoparticles were subjected to an alternating magnetic field or to macroscopic heating. Effect to these treatments were assessed at animal, cellular and molecular levels. Results: By comparing hsp70 expression following both treatments, thermotolerance pathways were found in both systems in absence of cell ablation or global temperature increment. Conclusion: Analysis of hsp70 transcriptional activation can be used as molecular thermometer to sense cells’ response to magnetic hyperthermia. Similar responses were found in cells and Hydra, suggesting a general mechanism to the delivery of sublethal thermal doses.
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Multifunctional siRNA glyconanoparticles trigger apoptotic pathways with the expression of cell death receptors and caspases and simultaneously trigger specific oncogene silencing via activation of the RNA interference pathway.
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In vitro primary screening for identifying bioactive compounds (inhibitors, activators or pharmacological chaperones) against a protein target results in the discovery of lead compounds that must be tested in cell-based efficacy secondary... more
In vitro primary screening for identifying bioactive compounds (inhibitors, activators or pharmacological chaperones) against a protein target results in the discovery of lead compounds that must be tested in cell-based efficacy secondary screenings. Very often lead compounds do not succeed because of an apparent low potency in cell assays, despite an excellent performance in primary screening. Primary and secondary screenings differ significantly according to the conditions and challenges the compounds must overcome in order to interact with their intended target. Cellular internalization and intracellular metabolism are some of the difficulties the compounds must confront and different strategies can be envisaged for minimizing that problem. Using a novel screening procedure we have identified 15 compounds inhibiting the hepatitis C NS3 protease in an allosteric fashion. After characterizing biophysically the interaction with the target, some of the compounds were not able to inhi...
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Multifunctional Eu:NaGdF4 nanospheres functionalized with polyacrylic acid (PAA) polymer have been prepared for the first time by a simple one-pot method that consists of a homogeneous precipitation reaction at 120 °C. The size of the... more
Multifunctional Eu:NaGdF4 nanospheres functionalized with polyacrylic acid (PAA) polymer have been prepared for the first time by a simple one-pot method that consists of a homogeneous precipitation reaction at 120 °C. The size of the nanospheres, which were polycrystalline and crystallized into a hexagonal structure, could be altered in the 60–95 nm range by adjusting the amount of polyacrylic acid added. The effects of Eu content and particle size of these nanomaterials on their optical properties (emission intensity and lifetime) as well as on their relaxivity (r1 and r2) values were also analyzed to find the optimum system for optical bioimaging and as a positive contrast agent for magnetic resonance imaging (MRI) applications. Finally, such optimum nanoparticles showed negligible cytotoxicity for Vero cells for concentrations up to 0.5 mg mL–1 and a high colloidal stability in 2-morpholinoethanesulfonic acid solutions, thereby satisfying the most important requirements for their use in biotechnological applications.
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Page 1. Multifunctional Glyconanoparticles: Applications in Biology and Biomedicine Soledad Penadés1,*, Jesus M. de la Fuente1, África G. Barrientos1, Caroline Clavel1, Olga Martínez-Ávila1, and David Alcántara1 Abstract ...
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Nanoparticles (NPs) can offer many advantages over traditional drug design and delivery, as well as toward medical diagnostics. As with any medical device or pharmaceutical drug intended to be used for in vivo biomedical applications, NPs... more
Nanoparticles (NPs) can offer many advantages over traditional drug design and delivery, as well as toward medical diagnostics. As with any medical device or pharmaceutical drug intended to be used for in vivo biomedical applications, NPs must be sterile. However, very little is known regarding the effect of sterilization methods on the intrinsic properties and stability of NPs. Herein a detailed analysis of physicochemical properties of two types of AuNPs upon sterilization by means of five different techniques is reported. In addition, cell viability and production of reactive oxygen species are studied. The results indicate that sterilization by ethylene oxide seems to be the most appropriate technique for both types of NPs. It is concluded that it is crucial to test several methods in order to establish the specific type of sterilization to be performed for each particular NP.
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Research Interests: Biomaterials, Biology, Malaria, Confocal Microscopy, Medicine, and 15 moreDendrimers, Multidisciplinary, Humans, Female, Animals, Cell Death, Drug Delivery Systems, In Vivo, Antimalarials, Chloroquine, Erythrocytes, Drug Carriers, Nanocarriers, Malaria Falciparum, and Human Umbilical Vein Endothelial Cells
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Nanoenabled technology holds great potential for health issues and biological research. Among the numerous inorganic nanoparticles that are available today, gold nanoparticles are fully developed as therapeutic and diagnostic agents both... more
Nanoenabled technology holds great potential for health issues and biological research. Among the numerous inorganic nanoparticles that are available today, gold nanoparticles are fully developed as therapeutic and diagnostic agents both in vitro and in vivo due to their physicochemical properties. Owing to this, substantial work has been conducted in terms of developing biosensors for noninvasive and targeted tumor diagnosis and treatment. Some studies have even expanded into clinical trials. This article focuses on the fundamentals and synthesis of gold nanoparticles, as well as the latest, most promising applications in cancer research, such as molecular diagnostics, immunosensors, surface-enhanced Raman spectroscopy and bioimaging. Challenges to their further translational development are also discussed.
Research Interests: Synthesis of nanoparticles, Nanomaterials Characterization, Nanobiotechnology, Nanocomposites, Nanomedicine, and 15 moreNanomaterials, Nanoparticles, Nanotechnology, Medicine, Nanobiotechnology and Biosensors, Metal Nanoparticles, Humans, Gold, Medical Biotechnology, Gold Nanoparticles, Nano Technology, Nanoscience, Nanoparticulate Drug Delivery System, Biosensing Techniques, and Colloidal Gold
In the last 30 years we have assisted to a massive advance of nanomaterials in material science. Nanomaterials and structures, in addition to their small size, have properties that differ from those of larger bulk materials, making them... more
In the last 30 years we have assisted to a massive advance of nanomaterials in material science. Nanomaterials and structures, in addition to their small size, have properties that differ from those of larger bulk materials, making them ideal for a host of novel applications. The spread of nanotechnology in the last years has been due to the improvement of synthesis and characterization methods on the nanoscale, a field rich in new physical phenomena and synthetic opportunities. In fact, the development of functional nanoparticles has progressed exponentially over the past two decades. This work aims to extensively review 30 years of different strategies of surface modification and functionalization of noble metal (gold) nanoparticles, magnetic nanocrystals and semiconductor nanoparticles, such as quantum dots. The aim of this review is not only to provide in-depth insights into the different biofunctionalization and characterization methods, but also to give an overview of possibilities and limitations of the available nanoparticles
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Multiple antibody immobilization methodologies have been developed for several applications including affinity chromatography, immunosensing, and drug delivery. Most of them have been carried out without considering the orientation of the... more
Multiple antibody immobilization methodologies have been developed for several applications including affinity chromatography, immunosensing, and drug delivery. Most of them have been carried out without considering the orientation of the antigen binding site of the antibody, or after the chemical modification of the antibody. An efficient immobilization to improve the biological activity of the antibody is one of the key fundamental issues to pursue. A simple and effective methodology for well-oriented covalently immobilization of antibodies on nanoparticles is reported in this chapter.
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DualT1andT2MRI contrast agents based on PEGylated manganese ferrite nanoparticles with long circulation times.
Research Interests: Materials Science, Magnetic Resonance Imaging, Nanoparticle, Medicine, Manganese, and 15 moreMolecular Imaging, Humans, Kidney, Liver, Mice, Female, Animals, Physical sciences, CHEMICAL SCIENCES, Particle Size, Manganese Compounds, Ferric Compounds, Magnetite Nanoparticles, Contrast Media, and nanoscale
Research Interests: Engineering, Algorithms, Chemistry, Water, Supramolecular Chemistry, and 15 moreSelf Assembly, Atomic Force Microscopy, Medicine, Graphite, Physical sciences, The, CHEMICAL SCIENCES, Hydrogen Bonding, Surface Properties, Glycolipids, CARBOHYDRATES, Disaccharides, Carbohydrate, Solvents, and Dimerization
Research Interests: Engineering, Chemistry, NMR Spectroscopy, X ray absorption spectroscopy, Nanoparticles, and 14 moreTransmission Electron Microscopy, Magnetic Resonance Spectroscopy, Medicine, Gold, Physical sciences, Magnetic Properties, Iron Oxide, The, CHEMICAL SCIENCES, Magnetics, Spectrometry, Spectrum analysis, Ferric Compounds, and Neoglycoconjugates
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Aims: Our aim is to explore whether gold nanoparticles (AuNPs) functionalized with a carboxylated polyethylene glycol (PEG) and protamine (AuNP@PEG@Prot) can modulate - enhance or restrain - DNA condensation, altering DNA conformation and... more
Aims: Our aim is to explore whether gold nanoparticles (AuNPs) functionalized with a carboxylated polyethylene glycol (PEG) and protamine (AuNP@PEG@Prot) can modulate - enhance or restrain - DNA condensation, altering DNA conformation and inducing structural changes. Understanding how these nanoconjugates modulate DNA structure, size and shape of DNA condensates, and enable control over the resulting 3D structures is of major biological and therapeutic importance. Materials & methods: Citrate-AuNPs were covered with a dense layer of a hetero-functional octa(ethylene glycol) (SH-EG(8)-COOH). Conjugation of protamine to the AuNP@PEG was achieved by taking advantage of the carboxylated surface previously generated on the surface of the NP and the remaining amino groups from the protamine, using carbodiimide and N-hydroxysulfosuccinimide coupling reactions. Results & conclusion: AuNP@PEG@Prot modulates the structure and topology of DNA, not only for condensation, but also for decondensa...
Research Interests: Chemistry, Nanomaterials Characterization, Nanobiotechnology, Nanocomposites, Nanomedicine, and 15 moreNanomaterials, Medicine, DNA, Gold, Medical Biotechnology, Gold Nanoparticles, Animals, DNA condensation, Histones, Biomimetic materials, DNA Topology, Colloidal Gold, Ethylene Glycol, Dimerization, and Nanoconjugates
Research Interests: Chemistry, Biomedical Engineering, Cell Adhesion, Medicine, Adhesion, and 15 moreClick chemistry, Cercopithecus aethiops, Biocompatibility, Humans, Animals, Light, In situ, HeLa cells, HeLa, Materials Testing, Photopolymer, Biocompatible Materials, Cell Survival, Photochemical Processes, and fibroblasts
Research Interests: Chemistry, Fluorescence Microscopy, Nanoparticle, Cell Adhesion, Scanning Electron Microscopy, and 14 moreMedicine, Multidisciplinary, Metal Nanoparticles, Biocompatibility, Humans, Gold, Endocytosis, Langmuir, Materials Testing, Colloidal Gold, Polyethylene Glycols, Ethylene Glycol, fibroblasts, and Ethylenediamine
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Molecular nanodiagnostics applied to cancer may provide rapid and sensitive detection of cancer related molecular alterations, which would enable early detection even when those alterations occur only in a small percentage of cells. The... more
Molecular nanodiagnostics applied to cancer may provide rapid and sensitive detection of cancer related molecular alterations, which would enable early detection even when those alterations occur only in a small percentage of cells. The use of gold nanoparticles derivatized with thiol modified oligonucleotides (Au-nanoprobes) for the detection of specific nucleic acid targets has been gaining momentum as an alternative to more traditional methodologies. Here, we present an Au-nanoparticles based approach for the molecular recognition and quantification of the BCR-ABL fusion transcript (mRNA), which is responsible for chronic myeloid leukemia (CML), and to the best of our knowledge it is the first time quantification of a specific mRNA directly in cancer cells is reported. This inexpensive and very easy to perform Au-nanoprobe based method allows quantification of unamplified total human RNA and specific detection of the oncogene transcript. The sensitivity settled by the Au-nanoprob...
Research Interests: Bioengineering, Bioinformatics, Biomedical Engineering, Molecular Biology, Computational Biology, and 15 moreMolecular Medicine, Biotechnology, Biology, Nanobiotechnology, Nanomaterials, Medicine, Nanobiotechnology and Biosensors, Molecular Recognition, Gold nanoparticle, Applied Microbiology and Biotechnology, Chronic myeloid leukemia, Early Detection, ABL, Early Diagnosis, and Differential Gene Expression
Research Interests: Materials Engineering, Chemical Engineering, Chemistry, Inorganic Chemistry, Magnetic Resonance Imaging, and 12 moreNanoparticles, Transmission Electron Microscopy, Medicine, Macromolecular X-Ray Crystallography, Animals, Luminescence, Gadolinium, Particle Size, Time Factors, Organometallic Compounds, Cell Survival, and Europium
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ABSTRACT No abstract available
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Research Interests: Bioengineering, Biochemistry, Bioinformatics, Genetics, Chemistry, and 15 moreAnalytical Chemistry, Biomedical Engineering, Immunology, Genomics, Computational Biology, Biotechnology, Cancer, Fluorescence, Biology, Cancer Biology, Medicine, Gene Silencing, Gold, Gold Nanoparticles, and Biosensing Techniques
Research Interests: Chemical Engineering, Materials Science, Analytical Chemistry, Biomedical Engineering, Carbon Nanotubes, and 15 moreComposite Materials, Carbon Nanotube, Nanotechnology, Medicine, Adsorption, Antibodies, Biosensor, Antibody, Immunoassay, Equipment Design, Equipment Failure Analysis, Biosensing Techniques, Nanotubes Carbon, Isoelectric point, and binding sites
Up to now, functionalized gold nanoparticles have been optimized as an effective intracellular in vitro delivery vehicle for siRNAs to interfere with the expression of specific genes by selective targeting, and provide protection against... more
Up to now, functionalized gold nanoparticles have been optimized as an effective intracellular in vitro delivery vehicle for siRNAs to interfere with the expression of specific genes by selective targeting, and provide protection against nucleases. Few examples however of suchlike in vivo applications have been described so far. In this study, we report the use of siRNA/RGD gold nanoparticles capable of targeting tumor cells in a lung cancer syngeneic orthotopic murine model. Therapeutic RGD-nanoparticle treatment resulted in successful targeting evident from significant c-myc oncogene down-regulation followed by tumor growth inhibition and prolonged survival of lung tumor bearing mice, possibly via αvβ3 integrin interaction. Our results suggest that RGD gold nanoparticles-mediated delivery of siRNA by intratracheal instillation in mice leads to successful suppression of tumor cell proliferation and respective tumor size reduction. These results reiterate the capability of functionalized gold nanoparticles for targeted delivery of siRNA to cancer cells towards effective silencing of the specific target oncogene. What is more, we demonstrate that the gold-nanoconjugates trigger a complex inflammatory and immune response that might promote the therapeutic effect of the RNAi to reduce tumor size with low doses of siRNA.
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The potential of a single molecular nanoconjugate to intersect all RNA pathways: from gene specific downregulation to silencing the silencers, i.e. siRNA and miRNA pathways, is demonstrated. Gold-nanobeacons are capable of efficiently... more
The potential of a single molecular nanoconjugate to intersect all RNA pathways: from gene specific downregulation to silencing the silencers, i.e. siRNA and miRNA pathways, is demonstrated. Gold-nanobeacons are capable of efficiently silencing single gene expression, exogenous siRNA and endogenous miRNAs while yielding a quantifiable fluorescence signal directly proportional to the level of silencing. The silencing potential is comparable to that of traditional siRNA but the same nanoconjugates structure is also capable of reversing the effect of an exogenous siRNA. We further demonstrate the Gold-nanobeacons' efficiency at targeting and silencing miR-21, an endogenous miRNA involved in cancer development, which could become a valid nanotheranostics approach. Again, expression of miR-21 was inhibited with concomitant increase of the Au-nanobeacons' fluorescence that can be used to assess the silencing effect. This way, a single nanostructure can be used to intersect all RNA regulatory pathways while allowing for direct assessment of effective silencing and cell localization via a quantifiable fluorescence signal, making cancer nanotheranostics possible.