Electrode Added (mg/mL) Detected (mg/mL) Recovery (%) RSD %
GCE-MWCNT-NiO 40 44.9 112.4 0.1
GCE-MWCNT-ZnO 40 39.1 97.8 0.13
GCE-MWCNT-Fe3O4 40 36.1 90.3 0.3
Table 4: Results of detection of DA in dopamine hydrochloride injection (n=5).