¹⁹F Oximetry with semifluorinated alkanes

Figures & data

Figure 1. Molecules of perflourohexyloctane (F6H8, a) and perfluorobutylpentane (F4H5, b) along with perfluoropentyloctane (F4H8, b). The largest resonance with an arbitrary chemical shift of 0 ppm in both 376.67 MHz–19F-spectra is affiliated to the CF3-group. The remaining resonances for F6H8 are at −32.7 ppm, −39.6 ppm, −40.5 ppm, −41.4 ppm and −44.1 ppm and belong to the CF2-components in the molecule. With less CF2-groups, F4H5 and F4H8 show identical spectra with resonances at 0 ppm, −32.7 ppm,−42.4 ppm and −44.1 ppm.

Figure 2. Linear regression of longitudinal relaxation rate R1 of F6H8, F4H8 and F4H5 versus oxygen partial pressure pO₂ at physiological temperature (37 °C). Additionally, HFB and F6H8 at 20 °C.

Figure 3. Linear relation of relaxation rate of F6H8 versus temperature at five O₂ values.

Table I. Comparison of temperature and pO₂ coefficients for various fluorine compounds for the relation [mmHg].

			Coefficients
			C	D	E	F
			1/s	1/(s·°C) 10^−3	1/(s·mmHg) 10^−3	1/(s·mmHg·°C) 10^−3
PFTB	7 T	Mason et al. 1993	1.647 ± 0.011	−21 ± 1	3.55 ± 0.10	2.74 ± 0.79
PFOB	4.7 T	Barker et al. 1994	0.384 ± 0.010	−3.7 ± 0.3	2.87 ± 0.9	−1.71 ± 0.26
PFOB	7 T	Mason et al. 1992	0.553	−5.9	2.3	−19
HFB	7 T	Liu et al. 2011	0.1500 ± 0.0040	−1.21 ± 0.12	2.69 ± 0.06	−2.74 ± 0.18
F6H8	9.4 T	This study	0.8534 ± 0.0417	−8.25 ± 1.16	2.34 ± 0.09	−2.87 ± 0.24
F4H8	9.4 T	This study	0.7188 ± 0.0002	−9.31 ± 0.01	1.16 ± 0.16	−0.39 ± 0.53
F4H5	9.4 T	This study	0.5221 ± 0.0002	−6.13 ± 0.01	1.30 ± 0.20	−0.30 ± 0.58

Table II. Coefficients at physiological temperature (37 °C) for the relation R1[1/s] = A + B·pO₂ [mmHg].

			Intercept A	Slope B	Sensitivity index B/A	Sensitivity related to temperature
			1/s	1/(s·mmHg) 10^−3	1/mmHg · 10^−3	mmHg/ °C
PFTB	7 T	Mason et al. 1993	0.8848 ± 0.0117	1.307 ± 0.023	1.47	8
PFCE	2 T	Dardzinski and Sotak 1994	0.33	1.9	5.8	5
PFCE	11.7 T	Mignion et al. 2013	1.7447	6.3	3.61	–
PFOB	4.7 T	Barker et al. 1994	0.247 ± 0.021	2.237 ± 0.186	5.23	–
PFOB	7 T	Shukla et al. 1995	0.290 ± 0.010	2.28 ± 0.08	7.86	–
PFOB	7 T	Mason et al. 1992	0.29	1.31	4.5	3
HFB	4.7 T	Mason et al. 1996	0.11 ± 0.01	1.03 ± 0.02	9.4	0.1
HFB	7 T	Liu et al. 2011	0.102 ± 0.003	1.658 ± 0.008	16.3	–
HFB	11.7 T	Mignion et al. 2013	0.63639	3.03	4.76	–
F6H8	9.4 T	This study	0.548 ± 0.085	1.278 ± 0.179	2.33 ± 0.49	13.6
F4H8	9.4 T	This study	0.381 ± 0.027	1.303 ± 0.053	3.42 ± 0.30	5.8
F4H5	9.4 T	This study	0.297 ± 0.018	1.183 ± 0.037	3.98 ± 0.27	6.6
HFB, 20 °C	9.4 T	This study	0.269 ± 0.391	1.289 ± 0.151	4.79 ± 0.90	–
F6H8, 20 °C	9.4 T	This study	0.661 ± 0.138	1.742 ± 0.444	2.64 ± 0.87	–

Figure 4. Dependence of longitudinal relaxation rate of pH at 20 °C and 21% pO₂. The slope of the fit function is equal to 0 within the error margin, so R1 and pO₂ do not correlate.

Mason RP, Shukla H, Antich PP. 1993. In vivo oxygen tension and temperature: simultaneous determination using 19F NMR spectroscopy of perfluorocarbon. Magn Reson Med. 29:296–302.

 PubMed Web of Science ®Google Scholar

Barker BR, Mason RP, Bansal N, Peshock RM. 1994. Oxygen tension mapping with F-19 echo-planar MR imaging of sequestered perfluorocarbon. J Magn Reson Imaging. 4:595–602.

 PubMed Web of Science ®Google Scholar

Mason RP, Shukla H, Antich PP. 1992. Oxygent: a novel probe of tissue oxygen tension. Biomater Artif Cells Immobilization Biotechnol. 20:929–932.

 PubMed Web of Science ®Google Scholar

Liu S, Shah SJ, Wilmes LJ, Feiner J, Kodibagkar VD, Wendland MF, et al. 2011. Quantitative tissue oxygen measurement in multiple organs using 19F MRI in a rat model. Magn Reson Med. 66:1722–1730.

 PubMed Web of Science ®Google Scholar

Dardzinski BJ, Sotak CH. 1994. Rapid tissue oxygen tension mapping using 19F inversion-recovery echo-planar imaging of perfluoro-15-crown-5-ether. Magn Reson Med. 32:88–97.

 PubMed Web of Science ®Google Scholar

Mignion L, Magat J, Schakman O, Marbaix E, Gallez B, Jordan BF. 2013. Hexafluorobenzene in comparison with perfluoro-15-crown-5-ether for repeated monitoring of oxygenation using 19F MRI in a mouse model. Magn Reson Med. 69:248–254.

 PubMed Web of Science ®Google Scholar

Shukla HP, Mason RP, Woessner DE, Antich PP. 1995. A comparison of three commercial perfluorocarbon emulsions as high-field 19F NMR probes of oxygen tension and temperature. J Magn Reson B. 106:131–141.

 Google Scholar

Mason RP, Rodbumrung W, Antich PP. 1996. Hexafluorobenzene: a sensitive 19F NMR indicator of tumor oxygenation. NMR Biomed. 9:125–134.

 PubMed Web of Science ®Google Scholar