. Author manuscript; available in PMC: 2017 Dec 19.

Published in final edited form as: Anal Bioanal Chem. 2016 Apr 12;408(15):4121–4131. doi: 10.1007/s00216-016-9503-2

Table 1.

Selection conditions for the aptamers

SELEX round no.	Target (GdCl₃) concentration	Counter selection
1	100 µM	None
2 – 4	50 µM	None
5 – 6	25 µM	None
7 – 10	10 µM	None
11 – 13	1 µM	None
14 – 16	100 nM	None
17 – 21	10 nM	DOTA, DTPA, Gd-DOTA and Gd-DTPA (at 1 µM initially and up to 1 mM)