Voltammetric analysis of hazardous azo-dye indigo carmine at simple and cost-effective carbon paste sensor modified with L-phenylalanine

Abstract

Indigo carmine (IC) is a hazardous synthetic dye and toxic to the humans but still it has been extremely employed in various industries. So it’s been a challenging for the determination of IC. In convenient to this, a reliable method of fabricated Poly (L-phenylalanine) modified carbon paste sensor (P(L-P)MCPS) for the study of electrochemical oxidation of IC is reported here. The fabrication was done by simple electro-polymerization technique. The biocompatible proposed sensor is characterized by Field Emission Scanning Electron Microscopy (FE-SEM), electrochemical impedance spectroscopy (EIS) and Cyclic Voltammetry (CV) studies. Differential Pulse Voltammetry (DPV) was utilized to assess the concentration of IC. The DPV studies display a linear range of 0.1 µM to 1 µM with lower detection limit of 0.0187 µM. The applicability of P(L-P)MCPS has been effectively verified in the analysis of real samples like hair dye powder, water and pharmaceutical tablet.

Graphical Abstract

Keywords:

• Indigo carmine
• poly (L-phenylalanine)
• carbon paste sensors
• voltammetry
• environmental monitoring
• electron transfer

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

Nambudumada S. Prinith is grateful for the financial support by KSTEPS, DST, Govt. of Karnataka fellowship [CHE-06: 2019-20]. Jamballi G. Manjunatha is thankful for the financial support from VGST, Bangalore under Research project. No. K-FIST (L2)/GRD-1020/2021-22/430.