Real-time Assay of Toxic Lead in In Vivo Living Plant Tissue

A method of detecting lead was developed using square wave anodic stripping voltammetry (SWASV) with DNA-carbon nanotube paste electrode (CNTPE). The results indicated a sensitive oxidation peak current of lead on the DNA-CNTPE. The curves were obtained within a concentration range of 50 ngL(−1)-20 mgL(−1) with preconcentration time of 100, 200, and 400 sec at the concentration of mgL(−1), μgL(−1), and ngL(−1), respectively. The observed relative standard deviation was 0.101% (n = 12) in the lead concentration of 30.0 μgL(−1) under optimum conditions. The low detection limit (S/N) was pegged at 8 ngL(−1) (2.6 × 10(−8) M). Results showed that the developed method can be used in real-time assay in vivo without requiring any pretreatment and pharmaceutical samples, and food samples, as well as other materials requiring water source contamination analyses.