Highlights

Every year, a committee of experts sits down with a tough job to do: from among all ICREA publications, they must find a handful that stand out from all the others. This is indeed a challenge. The debates are sometimes heated and always difficult but, in the end, a shortlist of  the most outstanding publications of the year is produced. No prize is awarded, and the only additional acknowledge is the honour of being chosen and highlighted by ICREA. Each piece has something unique about it, whether it be a particularly elegant solution, the huge impact it has in the media or the sheer fascination it generates as a truly new idea. For whatever the reason, these are the best of the best and, as such, we are proud to share them here.

LIST OF SCIENTIFIC HIGHLIGHTS

Format: yyyy

  • Cancer biomarkers detection using nanochannels (2011)

    Merkoçi, Arben (ICN2)

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    Cancer biomarkers detection using nanochannels

    A rapid nanochannel-based immunoassay capable of the filtering and subsequent detection of proteins in whole blood without any sample preparation is described. This is accomplished by using a nanoporous/nanochannel membrane modifi ed with antibodies, the conductivity of which toward a redox indicator is tuned by primary and secondary immunoreactions with proteins and gold nanoparticles. This interesting nanopore blockage by gold nanoparticles is enhanced by silver deposition that further decreases the diffusion of the signaling indicator through the nanochannel. The effi ciency of the nanochannels to act as immunoreaction platforms including the use of nanoparticles is also monitored by microscopic techniques. Successful detection of immunoglobulins including a cancer biomarker is achieved in buffer as well as in whole blood. This system constitutes an effi cient immunoassay capable of detecting up to 52 U mL-1 of CA15-3. The developed nanochannel/nanoparticle-based device can be used for several other proteins and extended also to DNA detection with interest not only for diagnostics but also environmental monitoring, food analysis, safety, and security applications. In this work we combine for the first time the capability of current tuning of a nanopore/nanochannel-based platform upon immunoblocking through nanoparticles for the detection of proteins, by taking advantage of an electrotransducer fabricated by screen-printing technology and a simple voltammetric detection mode. In addition, we show that the use of AuNP tags as blocking agents improves the detection limits of the label-free immunosensor. The catalytic properties of AuNPs upon silver deposition, applied also for protein detection, are examined for the in-nanochannel enhancement of AuNPs, which increases to a very high extent the pore-blocking efficiency and consequently the sensitivity of the assays. We also demonstrate for the
    first time the efficiency of the developed nanochannel/nanoparticle device for future applications in the direct detection of cancer biomarkers in whole blood, where the membranes act as both "filtering" and sensing platforms and thus avoid matrix effects.

    This work is highlighted by By Michael Berger. Copyright 2011 Nanowerk:
    http://www.nanowerk.com/spotlight/spotid=20257.php

  • Teamwork between tiny catalyst nanoparticles (2011)

    Neyman, Konstantin M (UB)

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    Teamwork between tiny catalyst nanoparticles

    Every football fan knows very well that a successful team needs players with different talents. It seems to be similar for complex chemical processes, which are accelerated by catalytic materials. These catalysts are composed of various components, only a few nanometers in size, whose cooperation is crucial: when the teamwork succeeds, the catalyst is modified and thus can become much more efficient than the individual active component.

    This was demonstrated by a group of researchers in an international collaboration of five European countries led by ICREA Professor Dr. Konstantin Neyman (Universitat de Barcelona) and Prof. Dr. Jörg Libuda (Universität Erlangen-Nürnberg, Germany) also involving groups from Sofia, Prague and Trieste. The results of the investigation have been published in the journal Nature Materials, 2011.

    Heterogeneous catalytic processes play a decisive role in efficient production of most chemicals and advanced materials, as well as in emerging key technologies for energy and the environment. The industrial catalysts are commonly extremely complex and it is very difficult to obtain insights at the microscopic level into the way they work. For this reason, most catalysts are optimised empirically, by a trial and error approach, so that making them is often close to "black magic".

    The international research team has managed to make systems, which model these catalysts. These permit on the one hand analysis by the most modern methods, such as by the synchrotron light, and on the other hand the use of modern, so-called quantum mechanical theoretical methods. Together, theory and experiment enable to obtain a detailed knowledge on these complex materials. It was then found that it was exactly this structure, which created the new properties of the material: the catalysts consist of oxide and metal particles of only a few nanometers in size, but they must be in close contact. The special chemical activity then is due to cooperation between the different components. Only when the components exist in the special form of nanoparticles can the highly reactive oxygen species be exchanged and open up new reaction paths. A catalyst made solely of metal or oxide does not work: like a football team that is all goal-keepers or all strikers.

  • A cocktail of antioxidants as a therapeutic hope for Lorenzo's oil disease (2011)

    Pujol Onofre, Aurora (IDIBELL)

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    A cocktail of antioxidants as a therapeutic hope for Lorenzo's oil disease

    Adrenoleukodystrophy (X-ALD) is a rare, lethal neurodegenerative disease of brain white matter caused by loss of function of the ABCD1 peroxisomal transporter of very long-chain fatty acids (VLCFA). There is currently no satisfactory therapy as a dietary approach, Lorenzo's oil, is not able to prevent or halt disease progression. The mouse model for X-ALD exhibits a late-onset neurological phenotype with axonal degeneration in spinal cords and associated locomotor disability, resembling the most common clinical presentation of X-ALD. Recently, we have identified oxidative damage as an early event in life, and the excess of VLCFA as a generator of radical oxygen species (ROS) and oxidative damage to proteins in X-ALD. To find the proof of principle for oxidative damage as main contributor to pathology, we have tested a combination of FDA-approved antioxidants: N-acetyl-cysteine, alpha-lipoic acid and alpha-tocopherol. In vitro, the three drugs act in a synergistic manner to scavenge VLCFA-dependent ROS generation. Further, in a preclinical setting, the cocktail of the three compounds reversed: i) oxidative stress and lesions to proteins, ii) immunohistological signs of axonal degeneration and iii) locomotor impairment in bar cross and treadmill tests (1). Thus, we have established a direct link between oxidative stress and axonal damage in a mouse model of neurodegenerative disease, and paved the way for translation into clinical trials. Currently, 20 X-ALD patients are enrolled on an open phase II clinical trial financed by the Spanish Ministry of Health and Hesperia Foundation (clinicaltrials.org NCT01495260). Endpoints include biochemical measures such as biomarkers of oxidative damage previously identified in our laboratory (2), and clinical outcomes, such as evaluation of spasticity scales and MRI images. As axonal degeneration is a main contributor to disability in progressive neurodegerative diseases in which oxidative stress is often associated as pathogenic factor, such as sclerosis multiple or Alzheimer disease, our results invites re-assessment of this combination of antioxidants in highly prevalent neurological disorders.

  • Carving at the nanoscale (2011)

    Puntes, Víctor F. (ICN2)

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    Carving at the nanoscale

    What do they have in common a maze, Russian dolls and the ship inside a bottle? The three are objects with internal structure and the three have always fascinated humans. These objects are formed differently: the gardeners sow the walls of the maze, the concentric dolls are modeled separately and assembled later, and the ship enters the bottle with a little string stretches and raises its sails. What never happens is that the sculptor or a gardener enters the initial structure, to model it by carving the final shape from the inside.
    This, not observed at the macroscopic scale, occurs spontaneously at the nanoscale if the ingredients are mixed properly. Nanotechnology allows a solid and compact structure, via chemical processes designed to attack, penetrate and advance digging the initial structure and creating geometric interconnected multi-cavity hollow structures ranging from molecular labyrinths to gold fullerenes, controlled by reaction fronts at the atomic level.
    These capsules protect and carry molecules. If additionally capsules are nanoscaled and inorganic, thanks to its high density of electronic states, they respond to light in resonance and therefore may be open or closed, heated, manipulated by electromagnetic fields such as a cocktail of drugs transported safely to the therapeutic target and drugs administered sequentially on top of pharmacology where the dose is controlled at the cellular level. Last but not least, the synthesis of these structures is performed by controlling processes considered previously undesirable: corrosion! So the recovery of old problems, applied to the nanoscale, results in new exquisite nanostructures.

    If being able to look, touch and manipulate matter at the nanoscale is already amazing, more amazing is that we are able to work inside the nanoparticle. The surface and interior of the nanostructures can be programmed in composition and architecture to make them like a tiny new research laboratory for chemical phenomena, optical, electrical, magnetic, thermal and mechanical stress. For example, it is possible to study quantum confinement phenomena or the coupling of internal and external walls excitations in the presence of electromagnetic radiation, or the study of internal catalytic reactions.

    This work has been developed by Dr. Edgar Gonzalez and Prof. Víctor Puntes at the Catalan Institute of Nanotechnology (ICN), in collaboration with Prof. Jordi Arbiol at the Materials Science Institute of Barcelona (ICMAB-CSIC). And this breakthrough opens a new route for med

  • Fossils of horse teeth indicate "you are what you eat" (2011)

    Rivals, Florent (IPHES)

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    Fossils of horse teeth indicate "you are what you eat"

    Fossil records verify a long-standing theory that horses evolved through natural selection. The records, spanning the past 55 million years, indicate a "critical" lag time between the evolution of horse teeth and dietary changes resulting from climate change.
    While some of the extinct populations examined had extremely abrasive diets, much of the time, it seemed horses had it surprisingly easy. This suggests that "strong natural selection" for different types of teeth only happened occasionally during brief intervals in horse history.
    A methodology known as dental mesowear analysis was used to reconstruct the diets of extinct species by measuring food-related wear and tear on fossil teeth. The data were analysed alongside records of North American climate changes that would have shifted the animals' diets from rainforest fruits and woody, leafy vegetation to the more abrasive diets found in grasslands.
    Lag time in the evolution of horse teeth in comparison to dietary changes is critical. Evolutionary changes in tooth anatomy lag behind the dietary changes by a million years or more.
    While paleontologists have long held horses as classic examples of evolution through natural selection, the theory has been difficult to test because the majority of horse species are extinct. However, the observation that dental changes in horses follow their dietary changes is consistent with evolution due to adaptation.
    The research shows that not only has the number of horse species been greatly reduced in the past few million years, but also that the diets of horses have been narrowly restricted. Living horses are anything but typical examples of the dietary ecology of this once great group of mammals.

  • Long-term projections and acclimatization scenarios of temperature-related mortality in Europe (2011)

    Rodó i López, Xavier (IC3)

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    Long-term projections and acclimatization scenarios of temperature-related mortality in Europe

    The steady increase in greenhouse gas concentrations is inducing a detectable rise in global temperatures. The sensitivity of human societies to warming temperatures is, however, a transcendental question not comprehensively addressed to date. Here we show the link between temperature, humidity and daily numbers of deaths in nearly 200 European regions, which are subsequently used to infer transient projections of mortality under state-of-the-art high-resolution greenhouse gas scenario simulations. Our analyses point to a change in the seasonality of mortality, with maximum monthly incidence progressively shifting from winter to summer. The results also show that the rise in heat-related mortality will start to completely compensate the reduction of deaths from cold during the second half of the century, amounting to an average drop in human lifespan of up 3-4 months in 2070-2100. Nevertheless, projections suggest that human lifespan might indeed increase if a substantial degree of adaptation to warm temperatures takes place.

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