Chip for optical analysis

Abstract

The present invention relates to a chip for optical analysis. In particular, the present invention relates to an optical sensor handling a liquid sample, which is a chip for analysis that can be used for selectively measuring a biologically-relevant substance or a chemical substance such as an environmental pollutant or a health affecting substance in a liquid to be measured. The chip for optical analysis of the present invention is characterized in that (1) an adsorption region (filter region) is provided between a sample introduction section and the observation section in a passage of the chip for analysis, (2) a bypass passage is provided in the passage (main passage) of the chip for analysis, and a time lag is generated between samples passed through the main passage and passed through a bypass passage, and (3) a measurement region and a reference region are provided in the observation section of the chip for analysis. In the present invention, the aspects (1) to (3) can be achieved individually or two or more thereof can be combined

1 . A chip for optical analysis comprising a substrate, a metal thin film on the substrate, and an observation section on the metal foil membrane, wherein the observation section comprises a measurement region and a reference region, and on the measurement region, a first substance having molecular selectivity that selectively interacts with a specific molecule is immobilized, and on the reference region, a second substance having molecular selectivity that is different only in selectivity to the specific molecule with which the first substance having molecular selectivity interacts and is comparable to the first substance having molecular selectivity in other characteristics is immobilized, and the first substance having molecular selectivity and the second substance having molecular selectivity are immobilized on the substrate by the same method. 
     
     
         2 . The chip for optical analysis according to  claim 1 , wherein the first substance having molecular selectivity and the second substance having molecular selectivity are antibodies or antigens of the same kinds. 
     
     
         3 . The chip for optical analysis according to  claim 1 , wherein the second substance having molecular selectivity is obtained by inactivating the first substance having molecular selectivity, and inactivation is achieved by irradiation with a high energy-ray selected from an X-ray, a gamma (γ)-ray, and an electron beam, heat treatment, electrochemical oxidation or reduction, or contact with an acidic or alkaline buffer. 
     
     
         4 . The chip for optical analysis according to  claim 1 , wherein the first substance having molecular selectivity and the second substance having molecular selectivity are DNA, and the second substance having molecular selectivity is obtained by replacing 10% or less of nucleotides constituting the first substance having molecular selectivity. 
     
     
         5 . The chip for optical analysis according to  claim 1 , wherein a plurality of observation sections each comprising the measurement region and the reference region as one set are provided in the passage on the substrate, and first substances having molecular selectivity different from each other are immobilized on the measurement region of the observation sections, so that each observation section can detect a different molecule.