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Donostia / San Sebastian, Spain

Continuous advances in the field of bionanotechnology, particularly in the areas of synthesis and functionalization of colloidal inorganic nanoparticles with novel physicochemical properties, allow the development of innovative and/or enhanced approaches for medical solutions. Many of the present and future applications of bionanotechnology rely on the ability of nanoparticles to efficiently interact with electromagnetic (EM) fields and subsequently to produce a response via scattering or absorption of the interacting field. The crosssections of nanoparticles are typically orders of magnitude larger than organic molecules, which provide the means for manipulating EM fields and, thereby, enable applications in therapy (e.g., photothermal therapy, hyperthermia, drug release, etc.), sensing (e.g., surface plasmon resonance, surface-enhanced Raman, energy transfer, etc.), and imaging (e.g., magnetic resonance, optoacoustic, photothermal, etc.). Herein, an overview of the most relevant parameters and promising applications of EM-active nanoparticles for applications in life science are discussed with a view toward tailoring the interaction of nanoparticles with EM fields. © 2014 The Authors. Source

Mourdikoudis S.,University of Vigo | Liz-Marzan L.M.,University of Vigo | Liz-Marzan L.M.,CIC Biomagune | Liz-Marzan L.M.,Ikerbasque
Chemistry of Materials | Year: 2013

Wet chemistry in organic solvents has proven highly efficient for the preparation of several types of metallic, metal-oxide, and semiconductor nanostructures. This Short Review focuses on the use of oleylamine (OAm) as a versatile reagent for the synthesis of various nanoparticle systems. We describe the ability of OAm to act as a surfactant, solvent, and reducing agent, as a function of other synthesis parameters. We also discuss the specific role of OAm either alone or in combination with other reactants, to form nanostructures using a variety of organic or inorganic compounds as precursors. In certain cases OAm can form complex compounds with the metal ions of the corresponding precursor, leading to metastable compounds that can act as secondary precursors and thus be decomposed in a controlled way to yield nanoparticles. We also point out that OAm-stabilized particles can often be dispersed in different organic solvents yielding solutions with enhanced colloidal stability over long times and the potential to find applications in a number of different fields. © 2013 American Chemical Society. Source

Soenen S.J.,Catholic University of Leuven | Parak W.J.,University of Marburg | Parak W.J.,CIC Biomagune | Rejman J.,University of Marburg | Manshian B.,Catholic University of Leuven
Chemical Reviews | Year: 2015

An overview of the current understanding of the behavior of iron oxide nanoparticles (IONPs), Q-Dots, silver and ZnO NPs, and Au NPs as a result of highly varying conditions to which they will be exposed when used in biomedical research or when distributed in the environment. It was shown that depending on the nature of the core material degradation of the NPs can occur, and its extent depends on the microenvironment to which they are exposed. In this connection, distinction should be made between degradation of the inorganic core, which highly depends on the material of the core, and degradation of the organic surface coating, which in particular affects colloidal stability and thus biodistribution of the NPs. For degrading NPs, the process of degradation brings along substantial difficulties in understanding their toxicological profile as not only the NP but also its released ions and the combination of the two can all have different biodistributions and toxic effects, which must be studied in detail. Other focus points are NP shape and size, where the ratio of surface area over volume should be kept as low as possible as degradation will occur at the surface of the NPs. Furthermore, the composition of the chemical core can be adjusted by the addition of other metal ions and hereby altering the matrix of the inorganic cores, which can result in enhanced chemical stability against pH-dependent degradation. Source

Rodriguez-Suarez E.,CIC Biomagune | Whetton A.D.,University of Manchester
Mass Spectrometry Reviews | Year: 2013

The systematic analysis of biological processes requires an understanding of the quantitative expression patterns of proteins, their interacting partners and their subcellular localization. This information was formerly difficult to accrue as the relative quantification of proteins relied on antibody-based methods and other approaches with low throughput. The advent of soft ionization techniques in mass spectrometry plus advances in separation technologies has aligned protein systems biology with messenger RNA, DNA, and microarray technologies to provide data on systems as opposed to singular protein entities. Another aspect of quantitative proteomics that increases its importance for the coming few years is the significant technical developments underway both for high pressure liquid chromatography and mass spectrum devices. Hence, robustness, reproducibility and mass accuracy are still improving with every new generation of instruments. Nonetheless, the methods employed require validation and comparison to design fit for purpose experiments in advanced protein analyses. This review considers the newly developed systematic protein investigation methods and their value from the standpoint that relative or absolute protein quantification is required de rigueur in biomedical research. © 2012 Wiley Periodicals, Inc. Source

PCNA is an essential factor for DNA replication and repair. It forms a ring shaped structure of 86 kDa by the symmetric association of three identical protomers. The ring encircles the DNA and acts as a docking platform for other proteins, most of them containing the PCNA Interaction Protein sequence (PIP-box). We have used NMR to characterize the interactions of PCNA with several other proteins and fragments in solution. The binding of the PIP-box peptide of the cell cycle inhibitor p21 to PCNA is consistent with the crystal structure of the complex. A shorter p21 peptide binds with reduced affinity but retains most of the molecular recognition determinants. However the binding of the corresponding peptide of the tumor suppressor ING1 is extremely weak, indicating that slight deviations from the consensus PIP-box sequence dramatically reduce the affinity for PCNA, in contrast with a proposed less stringent PIP-box sequence requirement. We could not detect any binding between PCNA and the MCL-1 or the CDK2 protein, reported to interact with PCNA in biochemical assays. This suggests that they do not bind directly to PCNA, or they do but very weakly, with additional unidentified factors stabilizing the interactions in the cell. Backbone dynamics measurements show three PCNA regions with high relative flexibility, including the interdomain connector loop (IDCL) and the C-terminus, both of them involved in the interaction with the PIP-box. Our work provides the basis for high resolution studies of direct ligand binding to PCNA in solution. Source

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