Table 1.
QMA equilibration and elution solution investigation
| QMA Equilibration Agent |
76/77Br Trapping (%) | Entry | QMA Elution Agent |
pKaa |
76/77Br Eluted (%) |
n |
|---|---|---|---|---|---|---|
| Na2SO4 (0.5 M) | 96 ± 4 % n = 11 |
1 | NH4OH | 9.23 | 93 ± 7 | 9 |
| 2 | Me3N | 9.8 | 99 | 1 | ||
| 3 | MeNH2 | 10.66 | 98 | 1 | ||
| 4 | Me2NH | 10.73 | 100 | 1 | ||
| 5 | DBU | 13.5 | 99 | 1 | ||
| NaHCO3 (0.5 M) | 99 ± 0.5 % n = 9 |
6 | NH4OH | 9.23 | 1 | 1 |
| 7 | Me3N | 9.8 | 5 ± 1 | 2 | ||
| 8 | MeNH2 | 10.66 | 55 | 1 | ||
| 9 | Me2NH | 10.73 | 86 ± 18 | 8 | ||
| 10 | Me2NHb | 10.73 | 94 ± 6 | 6 | ||
| 11 | DBU | 13.5 | 100 | 1 |
a
pKa values in aqueous solution from CRC Handbook of Chemistry and Physics Online except DBU from Kaupmees et al. Croat. Chem. Acta 87(4): 385–395 (2014).
b
Eluted with 1.6 mL of QMA releasing agent instead of the standard 800 μL. 0.1 M 1:1 MeCN / H2O