Zihua Yang

Expertise

• Surface functionalization & characterization 
• Metallic Nanoparticles synthesis & characterization 
• Localized Surface Plasmon Resonance (LSPR) biosensors
• Silica coating

Techniques 

• UV-VIS spectroscopy 
• DLS 
• QCM-D 
• IR 
• TEM/SEM microscopies 
• XPS 

PhD. subject 

Plasmonic nanoparticles for biosensing and therapy 

Summary 

Noble metal nanoparticles display fascinating properties mainly owing to their optical features resulting from the localized surface plasmon resonance (LSPR) effect. They absorb and / or scatter light in the visible to the NIR spectral region, depending on their size, shape, composition and state of surface. Any change of these parameters will result in a shift of the LSPR band position that may in turn result in a dramatic change of color, depending on the magnitude of the shift.

Several years ago, we have initiated research projects dealing with the use of noble metal nanoparticles for analytical purposes. For instance, we set up several metal nanoparticle-based biosensors to detect and quantify Enterotoxin A from Staphylococcus aureus (SEA), a biotoxin responsible for food intoxications. A solution phase, homogeneous assay was designed in which binding of SEA to antibody-gold nanoparticle bioconjugate resulted in a red shift of the LSPR band owing to the change of refractive index at the vicinity of the metal nanoparticles (Au or core-shell Au-Ag).