A5015337472- Organic Electronics and Photovoltaics
- Force Microscopy Techniques and Applications
- Crystallization and Solubility Studies
- Molecular Junctions and Nanostructures
- X-ray Diffraction in Crystallography
- Liquid Crystal Research Advancements
- Analytical Chemistry and Sensors
- Thin-Film Transistor Technologies
- Block Copolymer Self-Assembly
- Conducting polymers and applications
- Surface Chemistry and Catalysis
- Nanofabrication and Lithography Techniques
- Advanced Sensor and Energy Harvesting Materials
- Ionic liquids properties and applications
- Drug Solubulity and Delivery Systems
- Surfactants and Colloidal Systems
- Gas Sensing Nanomaterials and Sensors
- Crystallography and molecular interactions
- Innovative Microfluidic and Catalytic Techniques Innovation
- Fluid Dynamics and Thin Films
- Polymer Surface Interaction Studies
- Nanowire Synthesis and Applications
- Material Dynamics and Properties
- Synthesis and properties of polymers
- Perovskite Materials and Applications
Joanneum Research
2022-2024
University of Graz
2012-2022
Medical University of Graz
2022
Institute of Crystallography
2022
Graz University of Technology
2007-2019
BioTechMed-Graz
2015-2019
Université Libre de Bruxelles
2019
Elettra-Sincrotrone Trieste S.C.p.A.
2019
Research Center Pharmaceutical Engineering (Austria)
2019
University of Newcastle Australia
2010-2014
Combined experimental and theoretical investigations on thin films of pentacene are performed in order to determine the structure film phase. Grazing incidence x-ray diffraction is used for studying a with nominal thickness $180\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$. The crystal found exhibit lattice parameters $a=0.592\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, $b=0.754\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, $c=1.563\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$,...
Colloid probe atomic force microscopy has been used to study the nanotribological properties of silica–ethylammonium nitrate (EAN)–mica system. Normal curve measurements reveal a series steps at separations that are consistent with size an EAN ion pair (0.5 nm) due displacement structured solvent layers as two surfaces brought together. At closest separations, measured widths 0.3 nm and 0.1 nm, which too small be layer. The step is attributed partial silica-bound cation-rich layer, residual...
Control over drug delivery may be interestingly achieved by using temperature responsive encapsulants, which change their thickness and mesh size with temperature. The prototype N-isopropylacrylamide hydrogel cross-linked di(ethylene glycol) divinyl ether p(NIPAAm-co-DEGDVE) swells at low collapses above the lower critical solution (LCST), ∼29 °C in a buffer. It might expected that release from such encapsulation is always favored below LCST, due to larger free volume present swollen polymer...
GIDVis is a software package based on MATLAB specialized for, but not limited to, the visualization and analysis of grazing-incidence thin-film X-ray diffraction data obtained during sample rotation around surface normal. allows user to perform detector calibration, stitching, intensity corrections, standard evaluation (e.g. cuts integrations along specific reciprocal-space directions), crystal phase etc. To take full advantage measured in case rotation, pole figures can easily be calculated...
In this letter we demonstrate that particle suspensions in room temperature ionic liquids differ from aqueous some surprising and remarkable ways. Two results are of key importance. First, 1 μm diameter silica spheres do not aggregate pure ethylammonium nitrate (EAN) despite interparticle electrostatic repulsions being completely screened by its 11 M strength. However these dispersions become unstable the presence small amounts water. Using colloid probe atomic force microscopy (AFM),...
The presence of surface-induced crystal structures is well known within organic thin films. However, the physical parameters responsible for their formation are still under debate. In present work, we polymorphic molecule dihexyl-terthiophene in films prepared by different methods using solution-based like spin-coating, dip-coating and drop-casting, but also vapour deposition. characterised various X-ray diffraction to investigate crystallographic properties microscopy techniques (atomic...
Substrate-induced phases (SIPs) are polymorphic that found in thin films of a material and different from the single crystal or "bulk" structure material. In this work, we investigate presence SIP family [1]benzothieno[3,2-b]benzothiophene (BTBT) organic semiconductors effect aging solvent vapor annealing on film structure. Through extensive X-ray structural investigations spin coated films, find with significantly to crystals same forms; has herringbone motif while display layered π–π...
The preparation of typically thermodynamically unstable polymorphic structures is a challenge. However, solid surfaces are well established aids for the formation and stabilization within, instance, organic electronics. In this study, we report pharmaceutically relevant substance via surface at ambient conditions. Form III paracetamol, which in bulk standard conditions, can be stabilized with model silica by spin coating procedure followed rapid heat treatment. Such technique allows use...
The supramolecular rearrangements of biopolymers have remained difficult to discern. Here, we present a versatile approach that allows for an in situ investigation two major types typically observed with cellulose, the most abundant biopolymer on earth. Model thin films were employed study time-resolved pore size changes using grazing incidence small-angle X-ray scattering (GISAXS) during regeneration and drying.
The usage of amorphous solids in practical applications, such as medication, is commonly limited by the poor long-term stability this state, because unwanted crystalline transitions occur. In study, three different polymeric coatings are investigated for their ability to stabilize films model drug clotrimazole and protect against thermally induced transitions. For this, drop cast encapsulated initiated chemical vapor deposition (iCVD), using perfluorodecyl acrylate (PFDA), hydroxyethyl...
Small angle neutron scattering has been used to investigate the morphology of 38 kDa PEO dissolved in ethylammonium nitrate (EAN) dilute and semidilute concentration regions. At infinite dilution, radius gyration, R(g), is 8.1 nm. This value decreases through regime according a (c) dependence R(g) ≈ c(-0.24), while above overlap c(-1) followed. These values differ from aqueous solution behavior, which we attribute EAN being poorer solvent for than water; fact close θ solvent. The polymer...
Vapor‐phase deposition methods allow the synthesis and engineering of organic inorganic thin films, with high control on chemical composition, physical properties, conformality. In this review, recent applications vapor‐phase such as initiated vapor (iCVD), plasma enhanced (PE‐CVD), atomic layer (ALD), for encapsulation active pharmaceutical drugs are reported. The strategies emergent routes application vapor‐deposited films drug controlled release advanced nanostructured devices presented.
Abstract In recent decades, energy harvesting in rotating tires has been an active field of research as this could avoid the use toxic batteries, which are currently used to power pressure monitoring systems installed millions cars worldwide. However, due harsh mechanical conditions a tire and economic competition with low-cost widely spread self-powered (TPMS) have not yet entered market. work we present fully integrated bicycle tube system using multilayer piezoelectric harvester based on...
Polymorphism and morphology can represent key factors tremendously limiting the bioavailability of active pharmaceutical ingredients (API), in particular, due to solubility issues. Within this work, generation a yet unknown surface-induced polymorph (SIP) model drug, 5,5-diphenylimidazolidin-2,4-dion (phenytoin), is demonstrated thin films through altering crystallization kinetics solvent type. Atomic force microscopy points toward presence large single-crystalline domains SIP, which...
Abstract The order in molecular monolayers is a crucial aspect for their technological application. However, the preparation of defined by spin‐coating challenge, since involved processes are far from thermodynamic equilibrium. In work reported herein, dynamic formation dioctyl‐benzothienobenzothiophene explored as function temperature using X‐ray scattering techniques and atomic force microscopy. Starting with disordered monolayer after process, post‐deposition self‐reassembly at room...
Vapor-phase deposited polymer coatings are applied on thin indomethacin films to modify the drug release. Hydrogel-forming co-polymers of 2-hydroxyethyl methacrylate and ethylene glycol dimethacrylate were prepared directly top solution cast by initiated Chemical Vapor Deposition (iCVD). This technique allows for solvent-free processing under mild conditions, thus minimizing a potential impact pharmaceutical. The release behavior, among other properties, was evaluated polymers different...
The adsorption of poly(ethylene oxide) (PEO) and poly(propylene (PPO) onto silica from ethylammonium nitrate (a protic ionic liquid) has been investigated using colloid probe AFM force curve measurements. Steric repulsive forces were measured for PEO, confirming that PEO can compete with the cation adsorb silica. range repulsion increases polymer molecular weight (e.g., 1.4 nm 0.01 wt % 10 kDa to 40 300 PEO) concentration 16 at 0.001 78 0.4 PEO). Fits data could not be obtained standard...
Drying is a common pharmaceutical process, whose potential to alter the final drug properties-even at relatively low temperatures-is often neglected. The present study addresses impact of drying 20 and 50 °C on wet-extruded calcium stearate (CaSt) pellets. caused majority ibuprofen accumulate pellet surface due strong convective flow from pellet's center surface. In contrast, pellets dried still contained in interior higher rate associated film breakage during drying. Moreover, temperature...