Metal optical sensing assays

Optical Sensing Assays of Metal Ions Using Nanosensors... 

In this section, we describe theoretical methods that describe the macroscopic optical properties of metal nanoparticles (a.k.a quantum dots). Recently, silver and gold nanoparticles have foimd tremendous use in biological assays, detection, labelling and sensing because of their sensitive optical spectra. While some works in the literature refer to these as quantum dots , in optical absorption experiments their quantized energy structure is not probed. The spectrum is a probe of the localized surface plasmon phenomenon, a collective electronic excitation that is localized in spatial extent owing to the small size of the nanoparticle compared with the wavelength. 

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