1. sample pH value (e) and content of NaCl on the extraction performance of MIM/TIMA towards NPs. Conditions: (a) adsorption flow rate was 1.0 mL/min; and the volume of eluting solvent was 100 ?L ACN/FA (99/1.0, v/v); sample pH value did not be adjusted and no salt was added. The spiked concentration for each compound was 100 �g/L; (b) the sample volume was 30 mL, the other conditions and spiked concentration were the same as in Fig. 5a; (c) the adsorption flow rate was 1.2 mL/min, the other conditions and spiked concentration were the same as in Fig. 5b; (d) volume of eluting solvent (1.5% FA in ACN) was 90 �L, the other conditions and spiked concentration were the same as in Fig. 5c; (e) sample pH value was adjusted with 0.1 mol/L HCl or 0.1mol/L NaOH, the other conditions and spiked concentration were the same as in Fig;adsorption flow rate (b), content of FA in eluting solvent (c), volume of eluting solvent (d)