Filtern
Erscheinungsjahr
Dokumenttyp
- Posterpräsentation (27)
- Vortrag (26)
- Zeitschriftenartikel (23)
- Forschungsdatensatz (4)
- Sonstiges (3)
- Beitrag zu einem Tagungsband (2)
- Dissertation (1)
- Forschungsbericht (1)
Schlagworte
- DNA (57)
- Dosimetry (52)
- Geant4 (51)
- Microdosimetry (43)
- Radiation damage (41)
- Geant4-DNA (34)
- LEE (30)
- Low energy electrons (29)
- MCS (26)
- Radiation therapy (20)
- TOPAS (20)
- Ectoine (19)
- Protein (19)
- Simulation (18)
- G5P (16)
- Hydroxyl radical (16)
- DNA radiation damage (15)
- OH radical (15)
- ROS (15)
- TOPAS-nbio (15)
- Cancer treatment (14)
- Energy deposit (14)
- Monte-Carlo simulation (14)
- Base damage (12)
- Base loss (12)
- DNA damage (12)
- Ectoin (12)
- Monte-Carlo simulations (12)
- Proteins (12)
- Radiolysis (12)
- Single-strand break (SSB) (12)
- XPS (12)
- Particle scattering (11)
- Reactive oxygen species (11)
- Single-stranded DNA-binding proteins (11)
- AuNP (10)
- Dissociative electron attachment (DEA) (10)
- Double-strand break (DSB) (10)
- Hydrated DNA (10)
- Hydration shell (10)
- Ionization (10)
- NAP-XPS (10)
- Near ambient pressure xray photo electron spectroscopy (10)
- Prehydrated electron (10)
- Radioactive decay (10)
- Xray photo electron spectrocopy (10)
- Direct damage (9)
- Dissociative electron transfer (DET) (9)
- Electron irradiation (9)
- Hydrated electron (9)
- Hydroxyl radicals (9)
- Indirect damage (9)
- Ionizing radiation (9)
- Net-ionization reaction (9)
- PES (9)
- Particle scattering simulations (9)
- Quasi-direct damage (9)
- Radical (9)
- Radiotherapy (9)
- SAXS (9)
- Compatible solute (8)
- Hydroxyectoine (8)
- OH radicals (8)
- Radiationtherapy (8)
- Radical scavenger (8)
- Topas (8)
- Beta decay (7)
- Brachytherapy (7)
- Cancer therapy (7)
- ESCA (7)
- GVP (7)
- Gold Nanoparticles (7)
- LET (7)
- NP (7)
- Radiation protection (7)
- X-ray scattering (7)
- Xray (7)
- ssDNA (7)
- Bio-SAXS (6)
- Cosolute (6)
- Ionizing radiation damage (6)
- OH radical scavenger (6)
- Osmolyte (6)
- Presolvated electron (6)
- Protein unfolding (6)
- SSB (6)
- BioSAXS (5)
- Clustered nanoparticles (5)
- Ectoine radiation protection (5)
- Ionisation (5)
- LLG (5)
- Livermore model (5)
- McSAS3 (5)
- Micromagnetism (5)
- Nanoparticle (5)
- OH Radical (5)
- OOMMF (5)
- Penelope model (5)
- Radiation (5)
- Radical Scavenger (5)
- Small-angle xray scattering (5)
- Topas-MC (5)
- Topas-nBio (5)
- particle scattering (5)
- Aqueous solution (4)
- Cancer (4)
- DEA (4)
- DET (4)
- Exchange interaction (4)
- Ferromagnetism (4)
- Landau Lifshitz equation (4)
- Linear energy transfer (4)
- Magnetic moment (4)
- Nanoparticles (4)
- Object oriented micromagnetic framework (4)
- Particle scattering simulation (4)
- Raman spectroscopy (4)
- Stochastic Landau Lifshitz Gilbert equation (4)
- TOPAS-nBio (4)
- low energy electrons (4)
- Beta particle (3)
- DSB (3)
- Electrons (3)
- Gene five protein (3)
- Magnetic nanoparticles (3)
- OH-radical (3)
- Prehydrated electrons (3)
- Raman (3)
- Reference material (3)
- SEM (3)
- Salt (3)
- beta particle (3)
- Analytic (2)
- Biological structure (2)
- Biomolecules (2)
- Certification (2)
- DMSO (2)
- Desintegracion radioactiva (2)
- Dosimetrie (2)
- Dry DNA (2)
- Ectoine DNA interaction (2)
- Ectoine radical scavenger (2)
- Electron scattering (2)
- Gamma ray (2)
- Gel electrophoresis (2)
- Gold (2)
- Homogeneity (2)
- Hydrated electrons (2)
- Lethal dose (2)
- MOUSE (2)
- Monte Carlo simulation (2)
- Monte-Carlo Simulation (2)
- Monte-Carlo Simulations (2)
- Método de Montecarlo (2)
- Nanostructure quantification (2)
- OH (2)
- Organic osmolytes (2)
- Pharmacy (2)
- Plasmid DNA (2)
- Plasmid DNA in water (2)
- Polymers (2)
- Quality testing (2)
- Radiation damage to biomolecules (2)
- Radioactive nanoparticle (2)
- Referenzmaterialien (2)
- Round Robin (2)
- Scattering (2)
- Simulations (2)
- Solutions (pH, salinity, cosolutes) (2)
- Stability (2)
- Temeprature scaling (2)
- Temperature scaling (2)
- TopasMC (2)
- UV radiation (2)
- Water structure (2)
- nanoparticula (2)
- 266nm (1)
- AFM (1)
- AFM intermittent contact (1)
- AGE (1)
- Abasic site (1)
- Absorbed dose (1)
- Agarose gel electrophorese (1)
- Alpha (1)
- Amino Acids (1)
- Amino acid (1)
- Analysis (1)
- Au (1)
- BNP (1)
- Bacteriophage f1 (1)
- Beta elimination (1)
- Biodosimetry (1)
- Biologisches Dosimeter (1)
- Biopolymers (1)
- Bloch wall (1)
- Boehmite (1)
- Bragg peak (1)
- Buffer (1)
- Bystander effect (1)
- C++ (1)
- CPD (1)
- Cancer therapy (1)
- Carbon ions (1)
- Cell (1)
- Cell size (1)
- Cells (1)
- Cluster (1)
- Cmake (1)
- Co (1)
- Cobalt (1)
- Compatible solutes (1)
- Composites (1)
- Computer simulation (1)
- Computertomographie (1)
- Counterions (1)
- Curie temperature (1)
- Curve fitting (1)
- Cy3 (1)
- DFG (1)
- DFT calculations of Raman spectra (1)
- DNA Dosimeter (1)
- DNA base damage (1)
- DNA based data storage (1)
- DNA data storage (1)
- DNA degradation (1)
- DNA long term storage (1)
- DNA melting temperature (1)
- DNA protection (1)
- DNA reference material (1)
- DNA stability (1)
- DNA strand break (1)
- DNA strand-break (1)
- DNA vortexing (1)
- DNA-Binding protein (1)
- DNS (1)
- Damping factor (1)
- Data analysis (1)
- Debian (1)
- Direct laser writing (1)
- Domain wall (1)
- Dose (1)
- Double strand breaks (1)
- Double-strand break (1)
- ESEM (1)
- Ectoine DNA protection (1)
- Ectoine UV absorption (1)
- Ectoine hydration (1)
- Ectoine protein interaction (1)
- Ectoine salt (1)
- Ectoine-DNA binding (1)
- Effective dose (1)
- Effective irradiation dose 0.2-16 [Gy] (1)
- Electrohpresis (1)
- Electron Microscope (1)
- Electron irradiation 30 [kV] (1)
- Electron irradiation of DNA (1)
- Energiedosis (1)
- Energy dose (1)
- Epoxy (1)
- Equivalent dose (1)
- Exchange length (1)
- Excited states (1)
- FLASH effect (1)
- Fe (1)
- Fenton Reaction (1)
- Fermi resonance (1)
- Fityk (1)
- Fluorescence (1)
- Freezing (1)
- Functionalization (1)
- GV5 (1)
- Gamma (1)
- Gene-5 protein (1)
- Git (1)
- Gold Nanoparticle (1)
- H2O2 (1)
- Hairpin (1)
- High throughput (1)
- IR (1)
- IRPA (1)
- Interlaboratory comparability (1)
- Ion beam therapy (1)
- Iron (1)
- LL equation (1)
- Landau Lifshitz Gilbert equation (1)
- Linux (1)
- MCNP (1)
- MPL (1)
- MRT (1)
- Magnet coupling (1)
- Magnetic Nanoparticles (1)
- Magnetic anisotropy (1)
- Magnetic interacion (1)
- Magnetic nanoparticle (1)
- Magnetism (1)
- Magnetization dynamics (1)
- Mechanical properties (1)
- Mechanical stress (1)
- Median lethal energy deposit (1)
- Medizintechnik (1)
- Metal ions (1)
- Methodology (1)
- Micorscopic dose-damage relation (1)
- Micropatterning (1)
- Mitochondria (1)
- Molecular beacon (1)
- Monte Carlo (1)
- Monte carlo simulations (1)
- Monte-Carlo (1)
- Monte-Carlo Simulationen (1)
- Mussel-inspired materials (1)
- Nanodosimetry (1)
- Nanomaterials (1)
- Nanostructure (1)
- Nanostructuring (1)
- Neel wall (1)
- Ni (1)
- Nickel (1)
- Nucleobase (1)
- Nucleus (1)
- OH scavenger (1)
- Oligonucleotides (1)
- PBS (1)
- PIFE (1)
- Paramagnetism (1)
- Particle scatterin simulations (1)
- Phantome (1)
- Phase transition (1)
- Photons (1)
- Plasmid DNA pUC19 (1)
- Polycarbonate (1)
- Polydopamine (1)
- Polyglycerol (1)
- Polymer (1)
- Polymer degradation (1)
- Position of carboxylate group (1)
- Preferential exclusion (1)
- Protein-induced fluorescence enhancement (1)
- Protein–DNA filament (1)
- Quality control (1)
- Quencher (1)
- RBE (1)
- RNA (1)
- Radiadion damage (1)
- Radiation damage to DNA (1)
- Radical Scavenge (1)
- Radicals (1)
- Radioactive NP (1)
- Radioprotector ectoine (1)
- SBP (1)
- SPR (1)
- SYBR Gold (1)
- SYBR gold (1)
- Sall-angle scattering (1)
- Scavenger (1)
- Sem (1)
- Sensing (1)
- Single strand breaks (1)
- Single-strand break (1)
- Single-stranded DNA-binding protein (1)
- Size distribution (1)
- Small-angle scattering (1)
- Sodium chloride (1)
- Spin (1)
- Steel (1)
- Stochastic Landau Lifshitz equation (1)
- Strahlentherapie (1)
- Strand break (1)
- Strand breaks (1)
- Sun (1)
- Sunscreen (1)
- Superparamagnetism (1)
- Surface modification (1)
- Synthesis (1)
- TEM (1)
- THP(B) (1)
- Target volume (1)
- Targeted nanoparticle (1)
- Temperature (1)
- Temperature effects (1)
- Thawing (1)
- Therapy (1)
- Thermoplastics (1)
- Thermosets (1)
- Thetaevolve (1)
- Thin film systems (1)
- Topas-nbio (1)
- UV absorption (1)
- UV irradiation (1)
- UV photons (1)
- UV protection (1)
- UV-A (1)
- UV-B (1)
- UV-C (1)
- UV-Vis (1)
- Water (1)
- Xrays (1)
- Zwitterion (1)
- abasic side (1)
- base loss (1)
- clustered nanoparticles (1)
- dosimetry (1)
- dsDNA (1)
- gamma ray (1)
- geant4 (1)
- gold nanoparticles (1)
- lN2 (1)
- pH (1)
- pUC19 (1)
- presolvated electron (1)
- radiation Damage (1)
- radical scavenger (1)
- radicals (1)
- radiolysis (1)
- temeprature dependent exchange length (1)
Organisationseinheit der BAM
- 6 Materialchemie (71)
- 6.6 Physik und chemische Analytik der Polymere (71)
- 6.1 Oberflächen- und Dünnschichtanalyse (9)
- 6.5 Synthese und Streuverfahren nanostrukturierter Materialien (6)
- 5 Werkstofftechnik (2)
- 5.1 Mikrostruktur Design und Degradation (2)
- 6.3 Strukturanalytik (2)
- 4 Material und Umwelt (1)
- 4.1 Biologische Materialschädigung und Referenzorganismen (1)
Paper des Monats
- ja (2)
Eingeladener Vortrag
- nein (26)
To enhance the biological effects of radiation damage in cancerous cells, we present an alternative approach to the use of gold nanoparticles (AuNP), focusing on the synthesis and characterization of highly monodisperse, spherical radioactive gold nanoparticles 198AuNP. The size of the AuNP size was optimized with the help of Geant4/TOPAS particle scattering simulations, and energy deposition per nm3 per decay for varying radii (2–10 nm) was evaluated. This work is the foundation for ongoing experimental work to evaluate cell death induced by 198AuNP which aims for the use of radioactive gold nanoparticles in cancer treatment.
Dose enhancement by gold nanoparticles (AuNP) increases the biological effectiveness of radiation damage in biomolecules and tissue. To apply them effectively during cancer therapy their influence on the locally delivered dose has to be determined.[1] Hereby, the AuNP locations strongly influence the energy deposit in the nucleus, mitochondria, membrane and the cytosol of the targeted cells. To estimate these effects, particle scattering simulations are applied. In general, different approaches for modeling the AuNP and their distribution within the cell are possible. In this work, two newly developed continuous and discrete-geometric models for simulations of AuNP in cells are presented. [2] These models are applicable to simulations of internal emitters and external radiation sources. Most of the current studies on AuNP focus on external beam therapy. In contrast, we apply the presented models in Monte-Carlo particle scattering simulations to characterize the energy deposit in cell organelles by radioactive 198AuNP. They emit beta and gamma rays and are therefore considered for applications with solid tumors. Differences in local dose enhancement between randomly distributed and nucleus targeted nanoparticles are compared. Hereby nucleus targeted nanoparticels showed a strong local dose enhancement in the radio sensitive nucleus. These results are the foundation for ongoing experimental work which aims to obtain a mechanistic understanding of cell death induced by radioactive 198Au.
The formation of DNA-protein complexes ocurrs during replication and repair within cells. They are assumed to modify the damage caused by ionization radiation during radaition therapy. Hereby the assumption is, that the underlying damaging channels in DNA and proteins are modified, especially when compared to single molecules.
X-ray photoelectron-spectroscopy (XPS) allows simultaneous irradiation and damage monitoring. Although water radiolysis is essential for radiation damage, all previous XPS studies were performed in vacuum. Here we present near-ambient-pressure XPS experiments to directly measure DNA damage under water atmosphere. They permit in-situ monitoring of the effects of radicals on fully hydrated double-stranded DNA. Our results allow us to distinguish direct damage, by photons and secondary low-energy electrons (LEE), from damage by hydroxyl radicals or hydration induced modifications of damage pathways. The exposure of dry DNA to x-rays leads to strand-breaks at the sugar-phosphate backbone, while deoxyribose and nucleobases are less affected. In contrast, a strong increase of DNA damage is observed in water, where OH-radicals are produced. In consequence, base damage and base release become predominant, even though the number of strand-breaks increases further.
DNA long-term stability and integrity is of importance for applications in DNA based bio-dosimetry, data-storage, pharmaceutical quality-control, donor insemination and DNA based functional nanomaterials. Standard protocols for these applications involve repeated freeze-thaw cycles of the DNA, which can cause detrimental damage to the nucleobases, as well as the sugar-phosphate backbone and therefore the whole molecule. Throughout the literature three hypotheses can be found about the underlying mechanisms occurring during freeze-thaw cycles. It is hypothesized that DNA single-strand breaks during freezing can be induced by mechanical stress leading to shearing of the DNA molecule, by acidic pH causing damage through depurination and beta elimination or by the presence of metal ions catalyzing oxidative damage via reactive oxygen species (ROS). Here we test these hypotheses under well defined conditions with plasmid DNA pUC19 in high-purity buffer (1xPBS) at physiological salt and pH 7.4 conditions, under pH 6 and in the presence of metal ions in combination with the radical scavengers DMSO and Ectoine. The results show for the 2686 bp long plasmid DNA, that neither mechanical stress, nor pH 6 lead to degradation during repeated freeze-thaw cycles. In contrast, the presence of metal ions (Fe2+) leads to degradation of DNA via the production of radical species.
Models for TOPAS/Geant4 to estimate the microscopic dose received by biomolecules during bioSAXS experiments.
The C++ classes in this repository extend the functionality of the TOPAS (http://www.topasmc.org/) Monte-Carlo program, which is itself a wrapper of the Geant4 MCS Toolkit (http://geant4.org).
This dataset contains the processed and analysed small-angle X-ray scattering data associated with all samples from the publications "Bio-SAXS of Single-Stranded DNA-Binding Proteins: Radiation Protection by the Compatible Solute Ectoine" (https://doi.org/10.1039/D2CP05053F).
Files associated with McSAS3 analyses are included, alongside the relevant SAXS data, with datasets labelled in accordance to the protein (G5P), its concentration (1, 2 or 4 mg/mL), and if Ectoine is present (Ect) or absent (Pure). PEPSIsaxs simulations of the GVP monomer (PDB structure: 1GV5 ) and dimer are also included.
TOPAS-bioSAXS-dosimetry extension for TOPAS-nBio based particle scattering simulations can be obtained from https://github.com/MarcBHahn/TOPAS-bioSAXS-dosimetry which is further described in https://doi.org/10.26272/opus4-55751.
This work was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under grant number 442240902 (HA 8528/2-1 and SE 2999/2-1). We acknowledge Diamond Light Source for time on Beamline B21 under Proposal SM29806. This work has been supported by iNEXT-Discovery, grant number 871037, funded by the Horizon 2020 program of the European Commission.
Biopolymers are the building blocks of life. Their properties are exploited for material functionalization on the nanoscale in a flexible manner. An overview over current research activities in the field of sensing, nanostrcuturing, radiation damage measurements on DNA and proteins and microfluidics is given.