Synthesis, characterization and biofunctionalization of magnetic gold nanostructured particles

PAULINA LLORET; CARLOS MOINA; GABRIEL YBARRA; GLORIA LONGINOTTI; L. M. SOCOLOVSKY

MATERIALS RESEARCH BULLETIN

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2013

0025-5408

Magnetic Fe3O4@Au nanocomposite, nanostructured particles were prepared bydepositing gold onto seeds of superparamagnetic iron oxide nanoparticles (SPION). Theparticles were characterized by SEM, TEM, XRD, visible and near infraredspectroscopy, and magnetic measurements. They were also functionalized and employedas enzymatic carriers for electrochemical biosensing. The nanostructured particlesshowed an urchin-like morphology, roughly spherical particles whose surface wascovered with nanometric protuberances. The average diameter of the particles could becontrolled in the 100-500 nm range by changing the concentration of surfactants(oleylamine and oleic acid) employed in the synthesis. XRD showed a preferentialgrowth of {111} facets. 3-mercaptopropionic acid was used to chemically modify thesurface of the nanostructured particles and horseradish peroxidase was immobilizedonto the gold surface. Attached enzymes showed good activity even after several cyclesof magnetic collection, drying, and redispersion.