Fig. 9

Schematic drawing of the possible bioconjugation reaction between Fe₃O₄@CMD and AuNRs@BSA, in the presence of EDC and NHS. Nucleophilic attack by NH₂ group of BSA leads to the formation of an amide bond between COOH group of CMD and NH₂ group of BSA. EDC and NHS catalyze the covalent bindings between amino acid and carboxyl groups, thus, crosslinking AuNRs@BSA with the Fe₃O₄@CMD and forming AuNRs@BSA-Fe₃O₄@CMD