Regeneration of Enzymatic Layer on Layer-By-Layer Assembled Biosensor Interfaces

Previously, we reported an approach employing layer-by-layer (LbL) assembly of bio-functionalized multi-walled carbon nanotubes (MWCNT) on glassy carbon electrode for electrochemical detection of pesticides. In this study, to have a better understanding of self-assembled layers, surface morphology and element composition were characterized with Atomic Force Microscopy (AFM) and Scanning Electron Microscopy coupled with Energy-dispersive X-ray Spectroscopy (SEM/EDS). To further manipulate the versatile layer-by-layer assembly process, the possibility to regenerate the enzymatic layer in the layer-by-layer assembled bio-functionalized MWCNT Interfaces was investigated. Different approaches including direct chemical treatment, such as acid/alkali with different pH value, as well as inserting intermediate layer, such as conductive polymer PEDOT/NaPSS were explored. Such a strategy to achieve controllable assembly/disassembly of the layers is of great significance to enhance the biosensing system for long-term utility and/or multi-enzyme detection.