Each metal presents different characteristics when used in a surface plasmon resonance (SPR) experiment. These include
the shape of the SPR figure, the wavelength of better operation, the tendency to oxidize, the sensitivity to environmental
changes, the range of refractive indices detectable and the capability of binding to specific targets or analytes. When
choosing the metal for our SPR experiment all of these characteristics have to be taken into account. We investigate the
behavior of metals, which are less or have never been used in this kind of application, comparing their characteristics to
gold. We deeply investigate both theoretically and experimentally the behavior of palladium. This metal leads to an
inverted curve with a maximum of reflected intensity instead of a minimum. In fact, in this case we speak of Inverted
Surface Plasmon Resonance (ISPR). Aluminum and copper have also been considered because of their potentiality in
specific applications.
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