Table 7.

Effective diffusion coefficient values for [¹⁴C]-mannitol in 100-kDa MWCO polyethersulfone membranes of CMA/12 probes at 37°C obtained from point of no-fluid-flux extraction fraction values using Eqs. (51) and (52). For each probe the values for diffusional delivery from the perfusate to the external solution were similar to the values for diffusion in the opposite direction (sampling). However, the difference in mean values between probes was significant (2 tail t-test, P<0.03). The free diffusion coefficient (D_a) value used for mannitol at 37°C is 8.5 × 10⁻⁶ cm²/s [28].

	Dm×106, cm2/s
	Probe 4•1	Probe 4•2
Delivery (loss)	2.9	1.6
Sampling (gain)	3.1	1.8
Mean±SD	3.0±0.16	1.7±0.08
Dm/Da	0.35	0.20