Hani Nasser Abdelhamid, Hui-Fen Wu
National Sun Yat Sen University
Graphene magnetic nanosheet decorated with chitosan (GMCST) has been demonstrated as a promising biosensor for fluorescence spectroscopy and matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS) for sensitive pathogenic bacteria biosensing (Pseudomonas aeruginosa and Staphylococcus aureus) present in aqueous suspension or blood colloids. GMCST has been prepared and characterized using various techniques including TEM, UV, FTIR, XRD, Raman and fluorescence spectroscopy. Due to
the non-covalent interactions among the pathogenic bacteria with the GMCS, fluorescence enhancement takes place as a function of bacterial cell number with a low number of cell detection (4.5×102 to 5.0 × 102 cfu mL-1). GMCST also can be applied as an efficient separation and preconcentration nanoprobe for surface assisted laser desorption/ionization (SALDI) and enhances the ionization of bacterial biomolecules during MALDI-MS analysis. The bacterial cell suspension was concentrated from 1 mL to 10 mL via an external magnetic field, thus it can enhance bacteria detection for MALDI-MS analysis. GMCST is an outstanding approach which is a rapid, sensitive, culture free technique and low cost biosensor for pathogenic bacteria detection.