Marker | M_{w} | Radius (Å) | N^{1-f} | P × 10^{3g} (cm/hr) |
---|---|---|---|---|
[^{14}C]-mannitol | 184 | 3.9^{1-a}, (3.4)^{1-b} | 40 /13 | 4.1 ± 0.35 |
[^{3}H]-lactulose | 343 | 5.1^{1-a}, (4.8)^{1-b} | 6 /3 | 4.5 ± 0.79 |
[^{3}H]-PEG 400 | ∼400 | 5.5^{1-c}, (2.7)^{1-b} | 10 /4 | 4.5 ± 0.87 |
[^{3}H]-PEG 900 | ∼900 | 8.0^{1-c}, (8.4)^{1-d} | 9 /3 | 1.7 ± 0.31 |
[^{3}H]-PEG 4000 | ∼4000 | 15.9^{1-c}, (16.4)^{1-d} | 6 /3 | 0.7 ± 0.07 |
[^{3}H]-inulin | ∼5000 | 10.0^{1-e}, (13.9)^{1-d} | 9 /4 | 2.1 ± 0.24 |
↵1-a Estimated from Stokes-Einstein relationship with small-molecule correction reported by Steward, (1982), the value for lactulose is assumed to be similar to that for sucrose, a molecule similar in structure.
↵1-b Based on smallest cross-sectional diameter determined by computer modeling, reported by Hollander et al. (1988).
↵1-c Estimated from the relation D_{0} = 7 × 10^{−5} × M_{w} ^{−0.46} = kT/6πηR_{H}, where K is the Boltzmann constant, T = 298 K, the viscosity of water at 298 K is η = 0.000891 kg/msec (Handbook of Chemistry and Physics, 1988) and R_{H} is the hydrodynamic radius (Johansson et al., 1991 a, b).
↵1-d Measured by DLS in our laboratory.
↵1-e Based on the radius of a cylindrical solvated molecule (Middleton, 1977).
↵1-f N = number of tissues/number of animals.
1-g Average values ± standard errors × 10^{3}.