Students' seminar

Dedicated to the work principles of the giant magnetoresistance multiturn counter and possible ways to improve its performance, which includes both optimizitaion of the sensor shape and magnetic wire width modulation.

Diffusiophoresis, first described by Derjaguin et al. (1947), refers to particle motions driven by chemical gradients. With the aid of tracer velocimetry data and a 3-channel pH micro photometry experiment, both the underlying chemical gradient and resulting flow field can be mapped. Systems of interest are microfluidic devices employing large ion-exchange membranes as well as pH gradient-driven microswimmers.

I will show first results that liquid-liquid phase separation could play a role in clustering telomeres at the nuclear envelope. The interaction between telomeres and the NE is mainly based on hydrophobic interactions, which can be perturbed by Hexanediol or by mutations of the hydrophobic interacting sites in fission yeast.

IM30 is a protein involved in thylakoid membrane biogenesis and maintenance. IM30 forms large homooligomeric ring structures in solution and disassembles into carpet-like structures on lipid membranes. Membrane bound structures and the role of the intrinsically disordered regions (IDR) in IM30 are studied using atomic force microscopy (AFM) in combination with other biochemical and biophysical techniques.

The presentation introduces the single particle mass spectrometer ERICA-LAMS and the ND-MAX flight campaign. The campaign aims to investigate the contribution of aerosol particles of various chemical composition to the formation of contrails.

In this presentation, I will report on a novel nanogel platform based on polymerizable squaric ester amides for a more robust and hydrolysis-resistant post-polymerization modification of pH-degradable, immunodrug-loaded nanogels. Further, the nanocarrier's blood stability, biodistribution and potential protein corona are characterized showing that this nanocarrier can permit safe intravenous administation of immune modulators.

The development of new synthetic strategies towards bio-based materials is a current objective in academic and industrial research, motivated by increasing environmental awareness. We explored the utilization of terpenes as a naturally occurring feedstock in anionic polymerization of polymers. The nearly unlimited structural diversity of terpenes, ranging from acyclic and cyclic structures, to functional derivatives (terpenoids), gives access to tailor-made bio-based materials.

In this work we report the synthesis of telechelic poly(ethylene glycol)-peptide conjugates and their ability to form supramolecular hydrogels. The terminal peptide blocks contain the hydrophobic pentapeptide sequence FHFHF to promote pH-switchable β-sheet formation and self-assembly into nanorods as well as interstrand cross-linking for hydrogelation. By varying the peptide sequence, responsiveness to multiple external stimuli like temperature and ion concentration at physiologically relevant conditions can be observed.

I want to highlight the relevance of this class of compounds, what research I have already carried out and future research that is planned at the ATTO site in the Amazon, once I can travel there after Corona.

ABC triblock terpolymers are convenient building blocks for the synthesis of soft Janus nanoparticles (JNPs) by crosslinking the B domain that is “sandwiched" between A and C lamellae. In this presentation, I will show that the blending of homopolymer into a triblock terpolymer allows continuous tuning of the sandwiched microphase.

In many optical applications, Ru(II) and Ir(III) complexes are employed to exploit their strong charge transfer emission. But these metals are a limited resource and thus very expensive.Therefore, I am currently focusing on luminescent isoelectronic Mo(0) complexes using an earth-abundant metal center. In this talk I will give an overview over recent developments and present my newest results.

Many terrestrial beetles are able to walk on surfaces even in underwater conditions. This phenomena is explained by surface tension forces. The "hairy" legs of the insect secrete tiny amounts of an oily adhesive fluid, which allows it to attach to surfaces both in air and underwater.

Ultracold quantum gases realize almost ideal superfluids at temperatures close to zero Kelvin. Investigating such superfluids in time-dependent disorder potentials allows us probing the relaxation of nonequilibrium quantum systems. I will present our experimental results observing the response of a superfluid Fermi gas after disorder quenches.

Recent years have witnessed a surge of interest in the study of antiferromagnetic materials for spintronics applications. However, the absence of a net magnetic moment in antiferromagnets poses a major challenge to the visualization of their magnetic structure and it is usually resolved by complex synchrotron-based microscopy methods. I will discuss the possibility of imprinting antiferromagnetic domains on thin ferromagnetic overlayers via interfacial exchange coupling which enables us to image antiferromagnetic domains in-house using a scanning electron microscope with polarization analysis.