Table 2. Interfacial Liquid Layer Volume (V_IL), Total Liquid Phase Volume (V₀), Surface Area (A_s), Pore Volume (V_pore), and Bonding Density (ρ) for the Capcell Pak C18 Columns.

	acetonitrile			methanol
	ϕCH3CNBL	UG120	UG300	ϕCH3OHBL	UG120	UG300
	0.00	0.424 ± 0.032	0.265 ± 0.022	0.00	0.430 ± 0.029	0.265 ± 0.022
	0.01	0.468 ± 0.024	0.291 ± 0.032	0.01	0.440 ± 0.019	0.321 ± 0.013
VIL (mL)	0.05	0.498 ± 0.014	0.320 ± 0.026	0.05	0.463 ± 0.030	0.274 ± 0.031
	0.09	0.516 ± 0.026	0.352 ± 0.009	0.09	0.485 ± 0.045	0.259 ± 0.042
	0.19	0.563 ± 0.021	0.384 ± 0.027	0.19	0.470 ± 0.028	0.253 ± 0.047
V0 (mL)		2.744	3.158		2.659	3.158
As (m2 column–1)		378.05	248.86		399.13	248.86
Vpore (mL)		1.113	1.641		1.175	1.641
ρ (μmol m–2)a		2.5	3.7		2.5	3.7

^amanufacturer’s data.