Lead and cadmium can enter the human body through pathways such as air

water

food

and occupational exposure in workplaces.Long-term accumulation of lead and cadmium may impair human health.To address the insufficiency in the rapid determination of lead and cadmium exposure levels in urine samples

a novel electrochemical sensor is constructed by drop-coating carboxylated multi-walled carbon nanotubes(CMW

CNTs)/Nafion composites onto the surface of a glassy carbon electrode (GCE)and depositing an antimony (Sb)film via a preplating method.Differential pulse stripping voltammetry (DPSV)is employed to simultaneously determine the concentrations of lead ion(Pb

2+

) and cadmium ion(Cd

2+

) in urine samples.The results demonstrate a good linear relationship between the peak current and the concentrations of Pb

2+

and Cd

2+

in the range of 2.0~100.0μg·L

-1

with limits of detection (LOD)of 0.46μg·L

-1

and 0.38μg·L

-1

respectively.In practical urine sample tests

the spiked recoveries of Pb

2+

and Cd

2+

range from 96.53% to 103.35% and 93.87% to 96.59%

respectively

with relative standard deviations (RSD)below 10%.The sensor exhibits excellent selectivity

reproducibility

and stability

and has successfully realized simultaneous determination of Pb

2+

and Cd

2+

in urine.This work provides a new approach for assessing human exposure levels and public health monitoring.