What is the meaning of surface plasmon resonance?
Surface plasmon resonance (SPR) is the collective oscillation of conduction band electrons that are in resonance with the oscillating electric field of incident light, which will produce energetic plasmonic electrons through non-radiative excitation.
How does an SPR work?
SPR occurs when polarized light strikes an electrically conducting surface at the interface between two media. This generates electron charge density waves called plasmons, reducing the intensity of reflected light at a specific angle known as the resonance angle, in proportion to the mass on a sensor surface.
What is the SPR effect?
Surface plasmon resonance or SPR is an optical effect that can be utilized to measure the binding of molecules in real-time without the use of labels. SPR can be used, for example, to measure the binding between two proteins, a protein and an antibody, DNA and a protein, and many more.
What causes surface plasmon resonance?
Surface Plasmon Resonance is a phenomenon that occurs when polarized light hits a metal film at the interface of media with different refractive indices.
Why is surface plasmon resonance important?
Surface plasmon resonance (SPR) has become an important optical biosensing technology in the areas of biochemistry, biology, and medical sciences because of its real-time, label-free, and noninvasive nature.
Is Surface plasmon resonance expensive?
Commercial SPR devices are prohibitively expensive and require consumable sensor chips that fit certain specifications of size, thickness, and so forth.
Where is SPR used?
SPR can be used, for example, to measure the binding between two proteins, a protein and an antibody, DNA and a protein, and many more. It helps researchers determine which molecules interact, why they interact, and how strongly they interact.
What is SPR used for?
Surface plasmon resonance (SPR) binding analysis methodology is used to study molecular interactions (1, 2). SPR is an optical technique for detecting the interaction of two different molecules in which one is mobile and one is fixed on a thin gold film (1).
What is the basic principle behind the surface plasmon resonance method?
General Principle of SPR. Surface plasmon resonance occurs when a photon of incident light hits a metal surface (typically a gold surface). At a certain angle of incidence, a portion of the light energy couples through the metal coating with the electrons in the metal surface layer, which then move due to excitation.
Why gold is used in surface plasmon resonance?
In most cases, gold is used because it gives a SPR signal at convenient combinations of reflectance angle and wavelength. When the electrical field energy of the photon is just right, it can interact with the free electron constellations in the gold surface. These are the outer shell and conduction-band electrons.
How does surface plasmon resonance work?
Surface plasmon resonance occurs when a photon of incident light hits a metal surface (typically a gold surface). At a certain angle of incidence, a portion of the light energy couples through the metal coating with the electrons in the metal surface layer, which then move due to excitation.
When does the surface plasmon resonance ( SPR ) occur?
Surface Plasmon Resonance. The surface plasmon can be excited by the evanescent wave and this phenomenon is called surface plasmon resonance (SPR). When this happens, the intensity of the reflected light decreases sharply.
What kind of metal is used for surface plasmon resonance?
Typical metals that support surface plasmons are silver and gold, but metals such as copper, titanium or chromium have also been used. When using light to excite SP waves, there are two configurations which are well known.
What happens when surface plasmon is excited by evanescent wave?
The surface plasmon can be excited by the evanescent wave and this phenomenon is called surface plasmon resonance (SPR). When this happens, the intensity of the reflected light decreases sharply. The decays of the excited surface plasmon include energy conversion to phonons or photons.
Why are surface plasmon oscillations important for nanoparticles?
For nanoparticles, localized surface plasmon oscillations can give rise to the intense colors of suspensions or sols containing the nanoparticles.