. Author manuscript; available in PMC: 2019 Aug 1.

Published in final edited form as: Magn Reson Med. 2017 Dec 19;80(2):431–441. doi: 10.1002/mrm.27042

Table 3.

Summary of the chemical shift of the major peaks observed in this study and their assignments. Chemical shift values are reported with respect to the gas phase and to our water-based reference, obtained by scaling the water resonance frequency. Included is a summary of previous peak assignments.

Chemical Shift (ppm) Gas-referenced	Chemical Shift (ppm) Water-referenced	Previous Peak Assignments	Peak Assignments from this study
189.9 @ 31°C and 188.7@ 37°C	192.9 @ 31°C and 191.8@ 37°C	jaw muscle, fat	fat
192.3	194.9	brain tissue, white matter	CSF
195.7–196.2	198.7	brain tissue, gray matter	brain tissue, gray matter and maybe other tissues
195.6^a	198.8	---	muscular tissue, plasma
199.3^a	202.5	fat tissue	muscular tissue
210–212	213–214	red blood cells	red blood cells

Since no gas-phase ¹²⁹Xe signal was present in the in vivo muscle spectrum, these gas-referenced values were estimated by taking the CS difference between the water-referenced DPXe CS values for these peaks and the primary brain tissue peak, and adding the gas-referenced DPXe CS value for gray matter as reported in Rao et al (25).