2.5. ETC-Au-Fe3O4 NPs as a bifunctional sensor for Cd2+
The value of T2 was measured with a 0.5 T magnet NMI20-
Analyst (TW= 9000 ms, SF = 18 MHz, SW= 100 kHz, DRG1 = 3,
RG1 = 25 db). The solution of ETC-Au-Fe3O4 NPs (0.71 g/mL, Fe)
was mixed with different concentration of Cd2+ (increase from 10
to 320 M by 10 M at each point) and the mixture was incubated
for 25 min. The change in T2 was measured according to our
previous report [13].
The absorbance of ETC-Au-Fe3O4 NPs (21.18 g/mL, Fe) solution
mixed with different concentration of Cd2+ (increase from 10 to
190 M by 10 M at each point) incubated for 25 min was measure
by using UV–vis spectroscopy.
We use the same formula as in our previous study [11] to calculate
the limit of detection (LOD).