Dit proefschrift beschrijft een collectie aan alternatieve strategieën voor het begrijpen, ontwerpen en toepassen van lipide nanosystemen, waarin de rol van de bio-nano interacties centraal staan.... Show moreDit proefschrift beschrijft een collectie aan alternatieve strategieën voor het begrijpen, ontwerpen en toepassen van lipide nanosystemen, waarin de rol van de bio-nano interacties centraal staan. In het bijzonder wordt gekeken naar de interactie van RNA-lipide nanosystemen, bekend van de toepassing als vaccins en andere medicatie. Het onderzoeksgebied van de nanomedicatie kan gebruik maken van de specifieke voorbeelden die worden beschreven, maar er kan ook inspiratie worden opgedaan om de aanpak van onderzoek doen te verschuiven van een kostbare empirische aanpak naar rationeel gedreven ontwerpstrategie. Dit alles zal helpen in de ontwikkelen van nieuwe RNA therapieen in de toekomst. Show less
In this thesis, the effects of a new form of immunotherapy was investigated and studied how it can be used against different types of cancers. The investigated immunotherapy is based on injecting... Show moreIn this thesis, the effects of a new form of immunotherapy was investigated and studied how it can be used against different types of cancers. The investigated immunotherapy is based on injecting nanoparticles loaded with various immunologically active molecules (immunomodulatory nanoparticles) that can modulate the immune system to attack cancer cells more efficiently. The effectiveness of this immunomodulatory nanoparticles have been studied on different mouse cancer models and investigated as a single treatment or in combination with other known therapies, such as chemotherapy, therapeutic cancer vaccination, or photodynamic therapy. Show less
Metal complexes and 2D materials like graphene were combined to produce structures that can function as sensors. Using spin crossover materials, both in bulk single crystal form and in thin layer... Show moreMetal complexes and 2D materials like graphene were combined to produce structures that can function as sensors. Using spin crossover materials, both in bulk single crystal form and in thin layer form, graphene-based electronic sensors were produced and characterized that can detect spin switches in the spin crossover materials. At the same time, the light-activatable ruthenium complexes were researched for their application in sensors that can monitor reactions that were triggered by light. We found that the photoreaction of a ruthenium complex with a nucleobase could be triggered in paper-based graphene devices. Moreover, we found that this ruthenium scaffold could also be used to increase the signal strength in a nanopore-based DNA detection system. Lastly, a ruthenium complex was designed that had a sensing function built in, as a dual-function molecule with a sensing and anticancer function. Overall, combining metal complexes with graphene was found to be a successful strategy to produce hybrid structures for sensing. Show less
Graphene nanoribbons (GNRs) are used as a current carrying substrate in investigation of current-induced forces in a low-temperature STM (chapter 2). We demonstrate induced migration of Co adatoms... Show moreGraphene nanoribbons (GNRs) are used as a current carrying substrate in investigation of current-induced forces in a low-temperature STM (chapter 2). We demonstrate induced migration of Co adatoms on GNRs and on Au(111) using voltage pulses from the STM tip and we argue that motion is due to thermal excitations rather than the wind force. In chapter 3 we show that voltage signal is induced in a graphene strip when a droplet of ionic liquid is moved across its surface. Here we show that even deionized water can induce voltage over charged graphene surface due to the polarizability of water molecules. In chapter 4 we present a method for fabrication of graphene nanoelectrodes which we further test electrically in a modified STM. For the first time we demonstrate that the gap between two graphene nanoelectrodes can be tuned with subnanometric precision Show less
In this work, we illustrate unconventional approaches towards the fabrication of edge functionalized graphene nanostructures and bidimensional architectures in polymeric and metallic supports, with... Show moreIn this work, we illustrate unconventional approaches towards the fabrication of edge functionalized graphene nanostructures and bidimensional architectures in polymeric and metallic supports, with an outlook towards molecular sensing devices. Particularly, starting from the most established knowledge on the chemistry of graphene, we selectively functionalize the edges of graphene either via electrochemistry, plasma chemistry and solution chemistry. In fact, the chemistry at the edges, particularly at the nanoscale, tailors the properties of graphene without perturbing the honeycomb lattice of carbon atoms, thus without compromising the intrinsic nature of graphene. Via unconventional tools such as microtomy and molecular break junctions, we finally realize chemically designed platforms such as transistors, nanogaps and nanoribbons to be further integrated into sensing devices, such as zero-depth nanopore. Remarkably, we demonstrate the possibility of achieving extremely precise graphene nanostructures while going beyond the highly complicated demands of conventional top-down fabrications. At the same time, we specifically address the chemistry at the edges of graphene moving beyond synthetic approaches. Selectively edge functionalized graphene becomes available also on large area films and tailored graphene nanostructures, looking for the integration of graphene in the next generation sensing devices. Show less
Milanez, D.H.; Noyons, E.C.M.; Lopes de Faria, L.I. 2016
Advances concerning publication-level classification system have been demonstrated striking results by dealing properly with emergent, complex and interdisciplinary research areas, such as... Show moreAdvances concerning publication-level classification system have been demonstrated striking results by dealing properly with emergent, complex and interdisciplinary research areas, such as nanotechnology and nanocellulose. However, less attention has been paid to propose a delineating method to retrieve relevant research areas on specific subjects. This study aims at proposing a procedure to delineate research areas addressed in case nanocellulose. We investigate how a bibliometric analysis could provide interesting insights into research about this sustainable nanomaterial. The research topics clustered by a Publication-level Classification System were used. The procedure involves an iterative process, which includes developing and cleaning a set of core publication regarding the subject and an analysis of clusters they are associated with. Nanocellulose was selected as the subject of study, but the methodology may be applied to any other research area or topic. A discussion about each step of the procedure is provided. The proposed delineation procedure enables us to retrieve relevant publications from research areas involving nanocellulose. Seventeen research topics were mapped and associated with current research challenges on nanocellulose. Show less
Magnetic resonance force microscopy (MRFM) is a powerful technique to detect a small number of spins that relies on force detection by an ultrasoft magnetically tipped cantilever and selective... Show moreMagnetic resonance force microscopy (MRFM) is a powerful technique to detect a small number of spins that relies on force detection by an ultrasoft magnetically tipped cantilever and selective magnetic resonance manipulation of the spins. MRFM would greatly benefit from ultralow temperature operation, because of lower thermomechanical noise and increased thermal spin polarization. Here we demonstrate MRFM operation at temperatures as low as 30 mK, thanks to a recently developed superconducting quantum interference device (SQUID)-based cantilever detection technique, which avoids cantilever overheating. In our experiment, we detect dangling bond paramagnetic centres on a silicon surface down to millikelvin temperatures. Fluctuations of such defects are supposedly linked to 1/f magnetic noise and decoherence in SQUIDs, as well as in several superconducting and single spin qubits. We find evidence that spin diffusion has a key role in the low-temperature spin dynamics Show less
This thesis describes the investigation of crosslinked complexes of the blue copper protein azurin by means of spectroscopic techniques such as Uv-Vis and NMR as well as by X-ray crystallography.... Show moreThis thesis describes the investigation of crosslinked complexes of the blue copper protein azurin by means of spectroscopic techniques such as Uv-Vis and NMR as well as by X-ray crystallography. These non-physiological dimers serve as model systems for interprotein electron transfer (ET) and allow the investigation of various parameters that can influence the ET dynamics. By site-directed mutagenesis several mutant complexes have been created with tunable properties and/or high rates of electron transfer. The work presented here offers interesting new perspectives for the development of protein based biosensors on the nanometer scale. Show less