Single-cell detection by cavity ring-down spectroscopy
نویسندگان
چکیده
The implementation of cavity ring-down spectroscopy in an optical fiber resonator extends the viability of this highly sensitive technique for label-free detection of biological species. By chemically treating the surface of discrete tapered sensing regions along the length of a physically extended optical fiber resonator, we show single-cell sensitivity arising from optical scattering of the evanescent field surrounding the fiber. The observed detection limits, based on a minimum detectable scattering cross section on the order of 10 mm2, suggest a broad range of new applications in a simple, inexpensive device for real-time cavity ring-down biosensing. © 2004 American Institute of Physics. [DOI: 10.1063/1.1819520]
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