A comparative study of antibacterial properties and label-free electrochemical detection of digoxin based on MWCNTs-chitosan-Fe3O4/TiO2 composites

This study formulates biocomposites of chitosan, multi-walled carbon nanotubes (MWCNTs), iron oxide, and titanium oxide, characterizes their physical properties, and evaluates their antibacterial and biosensor toward digoxin detection. SEM was used to investigate morphology, whereas FTIR analysis peaks of active compounds of chitosan, MWCNTs, and composites were observed. The composites demonstrate strong antibacterial effects having ZOI 25, 12 mm; 35, 3 mm; and 43, 12 mm using M-chitosan, M-chitosan-TiO2, M-chitosan-Fe3O4 against S. aureus and A. baumannii, respectively. The composites were deposited on GCSPE to detect serum digoxin using CV. The biosensor can detect digoxin in the range 0-50 fM and 0-100 fM, with a detection limit of 0.8 pM and 0.03 pM for M-chitosan-TiO2 and M-chitosan-Fe3O4. The prepared biosensor showed strong specific recognition properties, ease, affordability of preparation, sensitive, and enable routine clinical analysis to identify trace amounts of digoxin. Thus, the present study developed composites with improved functional properties.