A novel three-dimensional electrochemical Cd(II) biosensor based on l-glutathione capped poly(3,4-ethylenedioxythiophene):polystyrene sulfonate/carboxylated multiwall CNT network

Abstract

The increased water contamination caused by heavy metal ions has negative consequences for human beings. The majority of these metal ions are incredibly poisonous, nonbiodegradable, and bioaccumulative. Therefore, the detection of these hazardous heavy metal ions is crucial in the current situation. The sensing mechanism of electrochemical biosensors must be understood to increase the sensing performance, such as selectivity, sensitivity, detection limit, repeatability, and reproducibility for application scenarios. The present investigation demonstrates the preparation of l-Glutathione modified Poly (3,4-ethylenedioxythiophene): polystyrene sulfonate/carboxylated multiwall carbon nanotubes (LGSH@PEDOT:PSS/MWCNTs-COOH) network by the solution processing method. The efficacy of the LGSH@PEDOT: PSS/MWCNTs-COOH network has been investigated using GIXRD, Raman, UV-Vis, FT-IR, AFM, CV, and EIS. The detection capability of the LGSH@PEDOT: PSS/MWCNTs-COOH network as a biosensor has been investigated utilizing the DPASV technique. The presented Cd(II) biosensor exhibited a sensitivity of 10.69 μA/ppm and a detection limit of 1 ppb. Moreover, the developed biosensor exhibited good selectivity, repeatability (RSD = 1.83%), and reproducibility (RSD = 4.73%). These favorable results make LGSH@PEDOT: PSS/MWCNTs-COOH electrode as an excellent Cd(II) ions detection probe as the next generation electrochemical biosensor to detect lungs, kidney, and breast cancers.

Keywords

• Heavy metal ion detection
• Cd(II) detection
• Electrochemical biosensing
• PEDOT:PSS
• MWCNTs-COOH
• LGSH tripeptide