Abstract: A method for forming an oligonucleotide comprises the steps of synthesizing a pair of oligonucleotides, one oligonucleotide having a base sequence portion comlementary to that of the other at a part of the terminal end region thereof; binding the pair of oligonucleotides at the complementary base sequence portions; and polymerizing nucleic acid bases onto the resulting pair of oligonuceotides. The method may further comprise the step of separating the oligonucleotides thus obtained into single strands.

Abstract: Lipid is determined quantitatively by treating a sample with a surfactant in an aqueous medium to obtain a liquid sample dispersion, then reacting the dispersion with a reagent containing cupric ion and bicinchoninic acid, and measuring a colored state developed by complex formation of bicinchoninic acid with cuprous ion formed from cupric ion in the presence of lipid. This method can be effectively applied to determination of amphiphilic lipid having a tendency of gathering in an aqueous medium. Further, two different species interfering with each other in quantitative determination thereof are determined respectively by conducting two different determination methods on the same sample followed by calculation using the values obtained.

Abstract: A labeled complex formed by combining a labeling agent with a biological substance, where the labeling agent is a trinucleus dye represented by the general formula (I)' or (II)':ring(Xa)-La-ring(Xb)-Lb-ring(Xc) (I)'?ring(Xa)-La-ring(Xb)-Lb-ring(Xc)!.sup..sym. Y.sup..crclbar.(II)'where the ring(Xa), ring(Xb), and ring(Xc), which mean rings having Xa, Xb, or Xc respectively, are independently a heterocyclic ring having one to three heteroatoms of oxygen, sulfur, nitrogen, or selenium, the heterocyclic ring being unsubstituted or substituted by any of a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted aralkyl group; La and Lb are independently a methine chain composed of one to six substituted or unsubstituted methine linkage, and one of La and Lb may be omitted to link directly the heterocyclic rings; and Y.sup..crclbar. represents an anion.

Abstract: A method for detecting a target nucleic acid comprises the steps of reacting a sample with a probe in the presence of two or more kinds of reagents capable of being made an irreversible change capable of being detected and accumulating by an interaction through a double helix structure under a condition enabling the replication of the formation and dissociation of a hybrid composed of the target nucleic acid in the sample and the probe, accumulating the irreversible change caused by the interaction of the reagents, and then detecting the accumulated change.

Abstract: A PCR amplification product is detected, in quantitative determination of nucleic acid and measurement of the number of bacterial cells or specific genes, by addition of a dye compound which does not fluoresce in the free state but fluoresces in the bonded state to a double-stranded nucleic acid.

Abstract: A stain for a nucleic acid characterized by containing, as an effective component, a pyrylium salt compound having Y as a negative portion and a pyrylium ring or a pyrylium-similar ring, wherein the ring is comprised of X selected from O, S, Se and Te as a hetero atom and has substituents R.sup.1, R.sup.2 and R.sup.3, wherein each of R.sup.1 and R.sup.2 is independently a hydrogen atom, sulfonate group, amino group, substituted or unsubstituted aryl group, etc., R.sup.3 is -A or -L-A, L is -L.sup.1 -, -L.sup.2 -L.sup.3 - or -L.sup.4 -L.sup.5 -L.sup.6 -, and each of L.sup.1 to L.sup.6 is independently --(CH.dbd.CH)--, a divalent group derived from the substituted or unsubstituted aryl group, etc., A is a substituted or unsubstituted aryl group, etc., and Y.sup.- is an anion.

Abstract: A method for detecting live individuals comprises a step of reacting a sample with a probe having a nonnatural type nucleic acid and a label substance linked with the nucleic acid, which nonnatural type nucleic acid contains a base sequence complementary to a base sequence of a target nucleic acid in the live target individuals to be detected and which probe is able to be incorporated into the live target individuals; and detecting the probe incorporated into the live target individuals by the utilization of the label substance of the probe when the live target individuals are present in the sample. A probe has a nonnatural type nucleic acid and a label substance linked with the nucleic acid, which nonatural type nucleic acid contains a base sequence complementary to a base sequence of a target nucleic acid in a live target individuals to be detected, and the probe is able to be incorporated into the live target individuals.

Abstract: Lipid is determined quantitatively by treating a sample with a surfactant in an aqueous medium to obtain a liquid sample dispersion, then reacting the dispersion with a reagent containing cupric ion and bicinchoninic acid, and measuring a colored state developed by complex formation of bicinchoninic acid with cuprous ion formed from cupric ion in the presence of lipid. This method can be effectively applied to determination of amphiphilic lipid having a tendency of gathering in an aqueous medium. Further, two different species interfering with each other in quantitative determination thereof are determined respectively by conducting two different determination methods on the same sample followed by calculation using the values obtained.

Abstract: A method for forming a proteoliposome comprises incorporating into a liposome a membrane protein combined with a carrier. Further, a method for preparing a giant proteoliposome, comprises freezing and thawing an alkali metal salt solution containing a membrane protein and a lipid, and subsequently dialyzing against a second salt solution or a buffer solution having a lower osmotic pressure than that of said alkali metal salt solution. Further, a method for forming a proteoliposome, comprises by freezing and thawing an alkali metal salt solution containing a membrane protein combined with a carrier and a lipid.

Abstract: A method of forming a lipid planar membrane of a bilayer membrane composed of lipid and protein comprises the step of immersing a substrate, which has a long-chain hydrocarbon group at least on the surface of one side thereof, in a suspension of liposome or proteoliposome, respectively. The long-chain hydrocarbon group is introduced into the substrate by bonding a long-chain alkylsilane coupling agent or a long-chain alkyltitanate coupling agent.

Abstract: A method for forming a proteoliposome comprises incorporating into a liposome a membrane protein combined with a carrier. Further, a method for preparing a giant proteoliposome, comprises freezing and thawing an alkali metal salt solution containing a membrane protein and a lipid, and subsequently dialyzing against a second salt solution or a buffer solution having a lower osmotic pressure than that of said alkali metal salt solution. Further, a method for forming a proteoliposome, comprises freezing and thawing an alkali metal salt solution containing a membrane protein combined with a carrier and a lipid.

Abstract: An ion permeable membrane, comprising two or more groups of substances having different sensitive wavelength regions in a lipid membrane, is provided.

Abstract: A recording medium is provided which comprises a recording layer comprising at least one set of image-forming units containing a region holding a photosensitive protein and a color-developing means capable of developing a color according to a change in the hydrogen ion concentration in the region. Each of said image-forming units within the same set having a photosensitive protein sensitive to a different wavelength.