Calcium carbide in mangoes: an electrochemical way for detection

Abstract

Calcium carbide (CaC₂), a carcinogen, is widely used for artificial ripening of mangoes. The usage of CaC₂ for mango ripening results in serious health issues like neurological disorders, ulcers, hypoxia, memory loss, etc. Identification of artificially ripened mangoes and quantification of CaC₂ in such fruits help in prevention of related health problems. The instability of CaC₂ in water makes its detection complex. In addition, the diffusion of calcium hydroxide (Ca(OH)₂) and acetylene (C₂H₂) into mangoes makes it more challenging. In this scenario, an electrochemical CaC₂ biosensor with a platinum (Pt) working electrode surface modified by a ceria (CeO₂) nano-interface and acetylcholinesterase (AChE) enzyme has been developed. The mechanism involves competitive inhibition of the Pt/CeO₂/AChE bioelectrode by the mixture of calcium peroxide (CaO₂) and C₂H₂. Different aspects of electrode immobilization with the nano-interface were probed using cyclic voltammetric and amperometric studies. The fabricated Pt/CeO₂/AChE bioelectrode exhibited a LOD of 0.6 nM with a linear range of 1–20 nM and % recovery in the range of 97.89–104.82.