Fig. 8. The extraction profile of adenosine by the MNPs-aptamer, MNPs-scrambled and the blank MNPs. Percolation: 500 L of buffer spiked with 2.5(g mL−1) adenosine. Washing: 300 L of 5% (v/v) MeOH. Elution: 200 L ofacetonitrile–water–acetic acid (0.1 M) (95:4:1, v/v/v).