An investigation of pipeline materials for continuous hyperpolarized 129Xe gas spectroscopy

In this study, five stainless steel tubes (STs) prepared with different surface film-forming processes were examined. The MR signal intensities of HP-129Xe gas that passed through each tube were then compared. The film passivated by iron fluoride maintained the highest level of hyperpolarization, whereas that passivated by chromium oxide maintained the lowest. A ST with an appropriate passive film may be a useful alternative to a Pyrex glass pipeline.