SENSING ELEMENT USING PHOTO-RESPONSIVE DNA THIN FILM

摘要

PROBLEM TO BE SOLVED: To measure a measuring fluid such as gas or liquid with good responsiveness and high sensitivity by using a photo-responsive DNA thin film 25 in a sensing element. SOLUTION: The photo-responsive DNA thin film 25 formed from a solution of DNA or hydrophobically processed DNA having a fluorescent molecule intercalated to a double spiral part or taken into a group or hydrophobic circumferential part is laminated on a solid substrate 22 through a metallic thin film 24 to form a measuring space closed by a translucent plate above the photo-responsive DNA thin film 25. The incident angleθof an excitation light L1to a prism 21 is adjusted by the rotating quantity of a rotary table 23 so that it is incident on one face of the prism 21 at an incident angleθexceeding the total reflection angle. The intensity of fluorescent L2emitted from the photo-responsive thin film 25 excited by the excitation light L1closed in the photo-responsive thin film 25 at a certain incident angle is sensitively changed at high speed by the interaction of the measuring fluid S fed to the measuring space V and the photo-responsive thin film 25, the fluorescent intensity is measured or spectrally analyzed by a fluorescence photospectrometer 33. The reflecting intensity change of the excitation light can be measured and analyzed with the high-sensitivity fluorescence measurement. COPYRIGHT: (C)2004,JPO