Fig. 4. DPV responses (a, c, e) and the corresponding calibration curves (b, d, f) of Co2P hybrid-SPE in 0.1 M PBS containing (a and b) 5 μM DA and 30 μM DA for different concentrations of AA, (c and d) 1 mM AA, and 30 μM UA for different concentrations of DA, and (e and f) 1 mM AA and 5 μM DA for different concentrations of UA.
