TY - JOUR
T1 - In vivo oximetry using a nitroxide‐liposome system
AU - Glockner, James F.
AU - Chan, Hsiao‐Chang ‐C
AU - Swartz, Harold M.
PY - 1991/7
Y1 - 1991/7
N2 - Liposomes containing the deuterated, charged, aqueous soluble nitroxide 4‐trimethylammonium‐2,2,6,6‐tetramethylpiperidine‐d16‐1‐oxyl (d‐Cat1) were used as probes to measure oxygen concentrations in vivo. Following intramuscular or intraperitoneal injection of the liposome suspension, ICR mice were placed over the surface probe of a low frequency (1.1 GHz) electron paramagnetic resonance (EPR) spectrometer. The linewidth of the deuterated nitroxide is sensitive to changes in the dissolved oxygen concentration: this parameter was calibrated separately so that linewidths measured in the injected mice could be converted into oxygen tensions. This technique detected substantial changes in pO2 as the oxygen content of the breathing gas was changed from 21 to 85 to 0%. Intravenous injection of the liposomes also is possible, and the liposomes accumulate in the liver and spleen, where detectable, oxygen‐sensitive EPR signals can be measured. © 1991 Academic Press, Inc.
AB - Liposomes containing the deuterated, charged, aqueous soluble nitroxide 4‐trimethylammonium‐2,2,6,6‐tetramethylpiperidine‐d16‐1‐oxyl (d‐Cat1) were used as probes to measure oxygen concentrations in vivo. Following intramuscular or intraperitoneal injection of the liposome suspension, ICR mice were placed over the surface probe of a low frequency (1.1 GHz) electron paramagnetic resonance (EPR) spectrometer. The linewidth of the deuterated nitroxide is sensitive to changes in the dissolved oxygen concentration: this parameter was calibrated separately so that linewidths measured in the injected mice could be converted into oxygen tensions. This technique detected substantial changes in pO2 as the oxygen content of the breathing gas was changed from 21 to 85 to 0%. Intravenous injection of the liposomes also is possible, and the liposomes accumulate in the liver and spleen, where detectable, oxygen‐sensitive EPR signals can be measured. © 1991 Academic Press, Inc.
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U2 - 10.1002/mrm.1910200113
DO - 10.1002/mrm.1910200113
M3 - Article
C2 - 1658535
AN - SCOPUS:0025779581
SN - 0740-3194
VL - 20
SP - 123
EP - 133
JO - Magnetic Resonance in Medicine
JF - Magnetic Resonance in Medicine
IS - 1
ER -