Table 2.
Aptamer | Small molecule |
1/Kads (SPR) | Kd (BSI) | Notes |
---|---|---|---|---|
21 | 1b | 49.9 ± 9.5 nM | 36.1 ± 23.6 pM | |
21-E | 1b | 223 ± 92 nM | 350 ± 240 pM | |
21-R | 1b | no binding b | no binding b | |
Qβ@21(s) a | 1b | n.a. | 30.0 ± 3.5 pM | |
Qβ@21(d) a | 1b | n.a. | 24.0 ± 2.4 pM | |
Qβ@21-E(s) a | 1b | n.a. | 3.4 ± 1.3 nM | |
Qβ@21-E(d) a | 1b | n.a. | 2.6 ± 1.1 nM | |
Qβ@21-R(s) a | 1b | n.a. | no binding b | |
Qβ@21-R(d) a | 1b | n.a. | no binding b | |
ThA | Theophylline | n.d. | 1.32 ± 0.53 nM | literature: 0.21 – 0.86 µM c–g |
ThA | Caffeine | n.d. | no binding b | literature: ~3.5 mM h |
The @ symbol denotes an aptamer packaged inside the Qβ virus-like particle shell; values of Kd are calculated per particle. (s) indicates the use of the single-pasmid method, and (d) notes the use of a dual-plasmid system.
No signal was observed at the highest ligand concentration tested.
0.4 µM (eq. filtration).44
0.21 µM (eq. filtration).45
0.30 µM (UV-vis).46
0.86 ± 0.12 µM (ITC).47
0.3 ± 0.1 µM (fluorescence).40
Affinity determination was not performed for this aptamer sequence and caffeine, so the value listed is for a similar theophylline aptamer with the same binding site sequence (TCT8-4).6
(n.a. = not applicable; n.d. = not determined.)