Abstract: A method for detecting a single nucleotide polymorphism in nucleic acids, characterized in that the method includes mixing (A) a nucleic acid probe comprising a nucleotide sequence complementarily hybridizable to an evaluation subject nucleic acid/an antisense strand thereof containing at least one single nucleotide polymorphism, and tagged with a nucleotide sequence of a hairpin structure having a bulge at a 5?-terminal thereof, wherein a guanine residue is introduced at an adjoining position of the bulge, and wherein a naphthyridine derivative compound is immobilized to the bulge; and (B) the evaluation subject nucleic acids; and detecting a signal ascribed to the naphthyridine derivative compound when the above nucleic acid probe and the above evaluation subject nucleic acids are hybridized, thereby evaluating the above single nucleotide polymorphism.

Abstract: A method is provided which enables quick, convenient, inexpensive, and high sensitivity confirmation of nucleic acid amplification after a nucleic acid amplification reaction. The DNA fragment in accordance with the present invention is a single-stranded DNA fragment containing a hairpin structure which in turn contains a bulge, wherein the DNA fragment is used as being attached to the 5? end of a primer used in nucleic acid amplification. The nucleic acid amplification confirmation method in accordance with the present invention quantifies a hairpin primer containing the DNA fragment at its 5? end by using bulge-binding fluorescent molecules after carrying out PCR or like nucleic acid amplification reaction using the hairpin primer. SNPs are detected quickly and conveniently at low cost and with high sensitivity by applying the nucleic acid amplification confirmation method, for example, to allele specific PCR.

Abstract: A small object identifying device and its identifying method according to which a large number of small objects can be identified. In one embodiment, the device includes a dispersion region section which disperses a large quantity of several kinds of small objects which are labeled by a combination of the presence/absence or measure of label elements of several kinds. A measuring device distributes and associates kinds of said label elements to two or more measurement points and measures the presence/absence or the measure of said label elements of the kinds which have been associated with respective measurement points. An identifying section associates the measurement results measured at each measurement point to thereby identify said small objects.

Abstract: The invention aims to provide an optical information reader which can identify precisely, reliably, and with high sensitivity, even when the quantity or the wavelength of light from a measuring object from which optical information is to be read, extends over a wide range.