Table 1. SPE with reconditioned cartridges^a.

NRR' =-NHBu
run	5a	5b	5c	5d	5e	5f
1	11mg	11mg	15mg	15mg	14mg	13mg
2	12	11	16	15	16	19
3	11	11	15	14	16	18
4	12	9	16	14	16	19
5	13	13	15	16	17	19
6	12	11	15	15	15	17
7	15	11	15	15	16	18
8	11	10	16	10	16	13
9	12	9	16	16	16	19
10	15	12	18	17	11	20

^a1% sample loading in THF (0.25 mL), samples were collected in 80:20 MeOH/H₂O (2x3 mL) fractions, cartridges were washed with MeOH (2x3 mL), acetone (2x3 mL), and then reconditioned with 80:20 MeOH/H₂O (2x3 mL) for next runs.