Fabrication of High performance bioanode based on fruitful association of dendrimer and carbon nanotube used for design O2/glucose membrane-less biofuel cell with improved bilirubine oxidase biocathode

In this study, the preparation of an integrated modified electrode based on the covalent attachment of glucose dehydrogenase (GDH) enzyme and safranin O to amine-derivative multiwalled carbon nanotubes (MWCNTs-NH2) modified glassy carbon (GC) electrode using G2.5-carboxylated PAMAM dendrimer (Den) as linking agent is reported. The obtained results indicated that the proposed system has effective bioelectrocatalytic activity toward glucose oxidation at 100mV with onset potential of −130mV (vs. Ag/AgCl). The performance of the prepared hybrid system of GC/MWCNTs-NH2/Den/GDH/Safranin as anode in a membraneless enzyme-based glucose/O2 biofuel cell is further evaluated. The biocathode in this system was composed of bilirubin oxidase (BOX) enzyme immobilized onto a bilirubin modified carbon nanotube GC electrode. Immobilized BOX onto CNTs/bilirubin not only show direct electron transfer but also it has excellent electrocatalytic activity toward oxygen reduction at a positive potential of 610mV. The open circuit voltage of the cell was 590mV. The maximum current density was 0.5mAcm−2, while maximum power density of 108μWcm−2 was achieved at voltage of 330mV. The immobilized enzymes in anode and cathode are very stable and output power of the BFC is approximately constant after 12h continues operation. •GCE modified with MWCNTs-NH2 and safranin using PAMAM-dendrimer as linking agent.•With covalent attachment of GDH enzyme a sensitive glucose biosensor was fabricated.•The integrated GC/MWCNTs-NH2/Den/GDH/Safranin system used as anode for biofuel cell.•The cathode of biofuel cell was BOX enzyme immobilized onto bilirubin/MWCNTs/GCE.•The voltage and power density of the biofuel cell were, 590mV and108μWcm−2.