An improving aqueous dispersion of polydopamine functionalized vapor grown carbon fiber for the effective sensing electrode fabrication to chloramphenicol drug detection in food samples

Antibiotic drugs are comprehensively used in treating infectious animals, mainly food-producing animals, which may severely affect other living organisms. Hence, it is necessary to develop a device to monitor trace level of these drug in food samples by a sensitive method. Carbon nanomaterials are usually fabricated as a disposable electrode in an electrochemical sensing application; however, its hydrophobicity nature causes poor electrode stability. An effective strategy is followed in this study to improve the aqueous dispersion of vapor-grown carbon fiber (VGCF) materials through the bio-inspired polydopamine (PDA) functionalization approach. The PDA functionalized VGCF (PDA-VGCF) is significantly characterized by spectroscopic and microscopic methods. The improved hydrophilicity of PDA-VGCF composite materials can offer an easy way to prepare catalyst slurry for the coating of a glassy carbon electrode (GCE) and used to determine the chloramphenicol (CAP) antibiotic drug. Interestingly, cyclic and differential pulse voltammetry studies are performed to observe the electrocatalysis of CAP using PDA-VGCF/GCE, displays a good linear response range (0.01-142 mu M), lower detection limit (3 nM), and higher sensitivity (0.68 mu A mu M- 1 cm-2) with long-time stability up to 30 days. Furthermore, PDA-VGCF/GCE shows an admirable selectivity while existing with other interference compounds and practical feasibility are also evaluated in apple juice, milk, and honey samples.

Automated summary

In this study, a bio-inspired polydopamine functionalization approach was used to improve the aqueous dispersion of vapor-grown carbon fiber materials. The resulting PDA-VGCF composite material showed enhanced hydrophilicity and was used for preparing a catalyst slurry for detecting chloramphenicol antibiotic drug.