2005 年 33 巻 9 号 p. 603-608
We have developed a highly sensitive optical fiber biosensor based on localized surface plasmon resonance. The sensor probe is constructed at an endface of the multimode optical fiber whose core diameter is 50pm, so that the effective surface area of the probe is about 0.002 mm2. It has the following advantages to the conventional biosensors:(a) it is easy to handle, (b) it enables us to probe a small amounts of samples<10μL, (c) label-free, and (d) low cost. This sensor has the highest resolution of 10-5 in refractive index, which corresponds to an adsorption amount of 10pg/mm2 on the probe surface. This value is similar to that of the conventional surface plasmon resonance biosensors that use an attenuated total reflection geometry.