2019, Korchak, Sergey, Emondts, Meike, Mamone, Salvatore, Blümich, Bernhard, Glöggler, Stefan

Hyperpolarized metabolites are very attractive contrast agents for in vivo magnetic resonance imaging studies enabling early diagnosis of cancer, for example. Real-time production of concentrated solutions of metabolites is a desired goal that will enable new applications such as the continuous investigation of metabolic changes. To this end, we are introducing two NMR experiments that allow us to deliver high levels of polarization at high concentrations (50 mM) of an acetate precursor (55% 13C polarization) and acetate (17% 13C polarization) utilizing 83% para-state enriched hydrogen within seconds at high magnetic field (7 T). Furthermore, we have translated these experiments to a portable low-field spectrometer with a permanent magnet operating at 1 T. The presented developments pave the way for a rapid and affordable production of hyperpolarized metabolites that can be implemented in e.g. metabolomics labs and for medical diagnosis.

2020, Rose, Jonas C., Fölster, Maaike, Kivilip, Lukas, Gerardo-Nava, Jose L., Jaekel, Esther E., Gehlen, David B., Rohlfs, Wilko, De Laporte, Laura

Living multicellular organisms comprise a high degree of soft anisotropic tissues but the development of controlled artificial assembly processes to mimic them remains challenging. Therefore, injectable, polymeric, magneto-responsive microgel rods are fabricated to orient within a low magnetic field. The incorporated superparamagnetic nanoparticles induce local dipole moments, resulting in a total magnetic torque that endows microgels with different structural, mechanical, and biochemical properties. In this report, a predictive macroscopic model based on an ellipsoidal element dispersed in a Newtonian fluid is adjusted using experimental data, which enables the prediction of the orientation rate and the required magnetic field strength for various microgel design parameters and fluid viscosities. The ordered microgels are fixed by crosslinking of a surrounding hydrogel, and can be employed for a wide variety of applications where anisotropic composite hydrogels play a crucial role; for instance as adaptive materials or in biomedical applications, wherein the model predictions can reduce animal experiments. © 2019 The Royal Society of Chemistry.