Table 1.

Projected retention of standard metabolites in 100% water (k′₀₀) on Hypercarb (4.6 mm × 100 mm, 3 μm) and BEH-C18 (2.1 mm × 50 mm, 1.7 μm) columns as well as the ratio of $\frac{{k^{\prime }}_{00}(\mathit{PGC})}{{k^{\prime }}_{00}(C18)}$. Retention was measured over a range of mobile phase compositions consisting of mixtures of water/MeOH + 0.1% FA at 30 °C. Experimental data was then fit with Equation 2, which was used to find k′₀₀.

Analyte	k′00 (PGC)	k′00 (C18)	$\frac{{k^{\prime }}_{00}(\mathit{PGC})}{{k^{\prime }}_{00}(C18)}$
MA	47	9.6	4.9
2-MHA	3300	23	140
HA	5800	15	390
3-MHA	13000	61	210
4-MHA	11000	61	180