Day 3 : November 8, 2017

Keynote Forum

Dr. Borja Sepulveda

ICN2, Spain

Keynote: Multifunctional magneto-plasmonic nanostructures for nanotherapies and imaging

Biography:

Borja Sepulveda received his PhD degree in Physics from the Complutense University of Madrid in 2005. His Post-graduate research was carried out at the Microelectronics Institute of Madrid (CSIC). In 2006 he started a two years Postoctoral stay at the Bionanophotonics and Bioimaging group in Chalmers University of Technology (Göteborg, Sweden). In 2008 he joined the Catalan Institute of Nanoscience and Nanotechnology (ICN2) of Barcelona as Research Fellow, where he got a Ramon y Cajal grant in 2009. From 2012, he holds a permanent research position at the ICN2. During his scientific career, he has acquired a highly multidisciplinary experience, focused on the development of photonic and magnetic nanostructures for biomedical and environmental control applications. In particular, he has acquired experience in very diverse fields such as: photonics and nano-photonics, magneto-optics and magneto-plasmonics, nano-fabrication,  surface chemistry and microfluidics. He is co-author of more than 50 publications, and the first author of three patents.

Abstract:

Magnetic nanostructures have demonstrated their enormous potential as biomedical nanodevices with both therapeutic and diagnostic activities. One of the most promising application is their use as heat mediators for magnetic fluid hyperthermia, where the nanostructures dissipate heat in the presence of alternating magnetic fields. Similarly, plasmonic nanostructures also exhibit encouraging properties in plasmonic absorption hyperthermia, where plasmonic nanostructures generate heat when irradiated with laser light. Thus, combining both properties in a single entity, i.e., magnetoplasmonic nanostructures, may open new avenues in the design of biomedical nanoplatfoms. Here we present two approaches for the design of magnetoplasmonic nanostructures for biomedical applications using bottom-up and top-down approaches. Magnetic-plasmonic nanoparticles of different sizes and morphologies based on Fe₃O4 and Au were synthesized by thermal decomposition (bottom-up). This method allows the synthesis of particles with high crystallinity, defined shape and narrow size distribution. Colloidal lithography (top-down) was used to develop magnetoplasmonic nanodomes based on Au and Fe. Both types of structures exhibit appealing magnetic properties at room temperature and clear plasmonic resonances. Hyperthermia measurements show that these nanostructures can be used as heat mediators in magnetic and plasmonic modes. Moreover, the combination or magnetic and plasmonic moieties confers the system additional functionalities like the capability to act as contrast agent for X-Ray Computed Tomography and optical imaging (Au) or as magnetic resonance imaging, MRI (Fe and Fe₃O₄). This combination of properties paves the way to use these hybrid nanostructures as potential theranostic (therapy-diagnostic) agents.    

Keynote Forum

Jordi Arbiol

ICREA & Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC & BIST, Spain

Keynote: Free-standing nanostructures at atomic scale: from growth mechanisms to local properties at the nanoscale

Biography:

Jordi Arbiol graduated in Physics at Universitat de Barcelona (UB) in 1997, where he also obtained his PhD (European Doctorate and PhD Extraordinary Award) in 2001 in the field of transmission electron microscopy (TEM) applied to nanostructured materials. He was Assistant Professor at UB. From 2009 to 2015, he was Group Leader at Institut de Ciència de Materials de Barcelona, ICMAB-CSIC. He is President of the Spanish Microscopy Society (SME), was the Vice-President from 2013 to 2017. Since 2015 he is the Leader of the Group of Advanced Electron Nanoscopy at Institut Català de Nanociència i Nanotecnologia (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST). He has been awarded with the 2014 EMS Outstanding Paper Award, the EU40 Materials Prize 2014 (E-MRS), listed in the Top 40 under 40 Power List (2014) by The Analytical Scientist and the PhD Extraordinary Award in 2001 (UB).

Abstract:

Technology at the nanoscale has become one of the main challenges in science as new physical effects appear and can be modulated at will. Superconductors, materials for spintronics, electronics, optoelectronics, sensing, energy applications and new generations of functionalized materials are taking advantage of the low dimensionality, improving their properties and opening a new range of applications. As developments in materials science are pushing to the size limits of physics and chemistry, there is a critical need for understanding the origin of these unique physical properties (optical and electronic) and relate them to the changes originated at the atomic scale, e.g.: linked to changes in (electronic) structure of the material. In the present work, I will show how combining advanced electron microscopy imaging with electron spectroscopy, as well as cathodoluminescence in an aberration corrected STEM will allow us to probe the elemental composition and electronic structure simultaneously with the optical properties in unprecedented spatial detail. The talk will focus on several examples in advanced nanomaterials for optical, plasmonic and energy applications. In this way the latest results obtained by my group on direct Visualizing and modeling materials at atomic scale will help to understand their growth mechanisms (sometimes complex) and also correlate their physical properties (electronic and photonic) at sub-nanometer with their atomic scale structure. The examples will cover a wide range of nanomaterials: quantum structures self-assembled in a nanowire: quantum wires (1D) and quantum dots (0D) and other complex nanowire-like morphologies for photonic and energy applications (LEDs, lasers, quantum computing, single photon emitters, water splitting cells, batteries), nanomembranes and 2D sheets; as well as metal multiwall nanoboxes and nanoframes for 3D plasmonics.

Keynote Forum

Heiko Jacobs

Nanotechnology group TU Iimenau, Germany

Keynote: Localized Programmable Gas Phase Electrodeposition; A new Transport Process with Applications Ranging from the Deposition of Functional Nanostructures to the Collection and Identification of Airborne Species for Sensing Applications

Biography:

Heiko O. Jacobs has his expertise in nanotechnology and heterogeneous integration of electronics over different length scales. His new deposition and assembling strategies established new integration strategies in solid, liquid and gas phase, which create new pathways for improving assembly techniques. He has built the ideas for this research during his Postdoc time at Whitesides in Harvard (99-01) and developed them during his time as a professor in Minnesota. Nowadays, these ideas are used in applications based on Nanoxerography, Gas Phase Electrodeposition and Fluidic Self-Assembly.

Abstract:

This talk describes a recently discovered transport approach that enables the localized deposition and collection of microscopic, nanoscopic, and molecular sized particles at high rates and in 3D. The localized gas phase deposition and collection process is based on the interplay of high mobility gas ions and lower mobility nanoparticles and molecules in the presence of a pre-patterned substrate. The first half of the talk will discuss an application where the approach is used to grow functional 3D nanostructures which are composed of metallic and semiconducting particles, including nanostructured electrodes for bulk heterojunction photovoltaics, multifunctional nanomaterial based sensors, plasmonic structures, and nanowire interconnects.[1,2]  The second half will discuss an extension to an application in the field of sensing of airborn analytes where the method is applied to locally collect molecules at collection rates that exceed diffusion-only-transport.[3,4,5] Specifically we will demonstrate localized collection of analytes over a wide range of molecular weights ranging from 3×10^17 to 1×10^2 Daltons, including (i) microscopic analyte particles, (ii) inorganic nanoparticles, all the way down to (iii) small organic molecules. Implications: In all cases we find that the collection rate is several orders of magnitudes higher than in the case where our advanced collection schemes is turned off and where collection is driven by diffusion only. The collection scheme is integrated on an existing surface-enhanced Raman spectroscopy based sensor. In terms of response time, the process is able to detect analytes at 9 parts per million within 1 second. As a comparison, 1 hour is required to reach the same signal level when diffusion-only-transport is used.

Keynote Forum

Valery Pavlov

CIC BiomaGUNE, Spain

Keynote: Effect of biocatalytic reactions on growth of semiconductor nanoparticles: Application to biosensing

Biography:

V. Pavlov obtained his PhD degree in Chemical Engineering in January 2005 from the University Rovira I Virgili (Spain). He worked in the Hebrew University of Jerusalem (Israel) in the group of professor Itamar Willner as a postdoctoral researcher. Since October he continued his postdoctoral study at the Chemistry Department of the University of Heidelberg (Germany).  In February 2007 he joined the new research institute CIC BiomaGUNE in San Sebastian as a group leader. His research interests include enzymatic generation of metal and semiconductor nanoparticles, production of new recombinant mutated enzymes, and  optical bioanalytical assays. 

Abstract:

Our laboratory discovered for the first time that products of enzymatic reactions are able to modulate growth of semiconductor fluorescent CdS nanoparticles (NPs) grown in situ. Emission spectra of these NPs depend on their size and capping agents which stabilize them in aqueous solutions. We found out experimental conditions under which the growth of CdS NPs is very rapid  and takes 10 min or less. The biocatalytic growth of CdS NPs has been applied to optical determination of enzymatic activities of enzymes such as acetylcholine esterase,¹ horseradish peroxidase,² glucose oxidase³ etc. We also reported novel sensitive selective electrochemical assays based on generation of CdS NPs in situ which is modulated by affinity interactions and oxidative activity of metal ions. For example, our immunoassay employs antibody-alkaline phosphatase conjugate which catalyzes generation of CdS detected with disposable carbon electrodes premodified with the electroconductive polymer Os-PVP.⁴ We demonstrated a new electrochemical assay employing microbead linked enzymatic generation of CdS QDs (Microbead QD-ELISA)⁵  for cancer marker superoxide dismutase. In the presence of this analyte, CdS NPs were formed on the surface of microbeads modified with antibodies for superoxide dismutase (Fugure 1). Formed in situ CdS NPs were followed with fluorescence spectroscopy, microscopy, and square-wave voltammetry. Our latest assays use cysteine (CSH) which stabilizes CdS NPs growing during the biorecognition event  in aqueous buffered solutions. Oxidation of CSH with hydrogen peroxide (H₂O₂) results in formation of cystine (CSSC) which does not stabilize CdS NPs. A number of chemical and biochemical reactions involving copper ions, glucose⁶ and methanol yield hydrogen peroxide, modulating the quantity of CdS NPs produced in situ.