Salle de réunion, Bât.129.
Hyperpolarized xenon is an exquisite NMR probe for sensing molecular environments of the noble gas in solution. By trapping it in molecular cages like cryptophane-A, Xe-129 can report information about molecular-specific binding events or resolve multiple signals simultaneously from different micro-environments in a lipid emulsion – a macroscopically-homogeneous phase that mimics properties of biological relevance. The recently proposed Hyper-CEST detection scheme can be used in this context to pair significant signal enhancement with high specificity of NMR resonances. When combined with highly frequency-selective pulses, it also allows for demonstration of multiplexing potential using a single cage type as contrast agent for different environments in NMR imaging. Based on the results of CEST experiments at different frequencies, we conclude that there are multiple pathways with different dynamic characteristics for the exchange of xenon with its host in the multiple micro-environments.
Leibniz-Institut für Molekulare Pharmakologie, Berlin