Substance sealing method and target molecule detecting method
As a technique for efficiently sealing many substances, such as beads, nucleic acid, protein, virus, cells, and lipid membrane complex, into an array, the present invention provides a method for sealing a substance, including: (i) a step of introducing a first solvent containing a substance on a substrate on which a plurality of receptacles capable of storing the substance are formed separated from each other by a side wall; and (ii) a step of introducing a second solvent having a greater specific gravity than that of the first solvent onto the first solvent, the step (ii) being carried out after the step (i).
1. A method for sealing a substance in a receptacle, the method comprising:
(i) a step of introducing a hydrophilic solvent containing the substance and a surfactant on a substrate, wherein
the substrate has a hydrophilic surface,
a container wall extends above the substrate,
the surface of the substrate and the container wall form an opened well,
a plurality of receptacles capable of storing the substance are formed, separated from each other by a side wall, on the hydrophilic surface of the substrate, and
the side wall has a hydrophobic upper surface; and
(ii) a step of introducing a hydrophobic solvent having a greater specific gravity than that of the hydrophilic solvent onto the hydrophilic solvent so that the hydrophobic solvent moves down below the hydrophilic solvent due to its greater specific gravity than that of the hydrophilic solvent and thereby the hydrophilic solvent is substituted by the hydrophobic solvent, thereby to form droplets of the hydrophilic solvent within the plurality of receptacles covered with the hydrophobic solvent, the step (ii) being carried out after the step (i);
wherein
the hydrophobic solvent is introduced on the hydrophilic solvent from the opening of the opened well, and
at least one of the droplets of the hydrophilic solvent formed within the plurality of receptacles covered with the hydrophobic solvent contains the substance.
2. The method as set forth in claim 1 , wherein the surfactant is polyoxyethylene sorbitan monolaurate or polyethylene glycol mono-4-octylphenyl ether.
3. The method as set forth in claim 1 , wherein the surfactant has a concentration of 0.01% by weight to 1% by weight.
4. The method as set forth in claim 1 , wherein the hydrophobic solvent is at least one selected from the group consisting of saturated hydrocarbon, unsaturated hydrocarbon, aromatic hydrocarbon, silicone oil, hexafluoropropylene epoxide polymer, a polymer having a hydrofluoroether structure, perfluoropolyether, chlorotrifluoroethylene polymer, and a polymer having a perfluorocarbon structure, or is a mixed solvent that includes at least one of these solvents.
5. The method as set forth in claim 1 , wherein the hydrophilic solvent is at least one selected from the group consisting of water, hydrophilic alcohol, hydrophilic ether, ketone, nitrile solvents, dimethyl sulfoxide, and N,N-dimethylformamide, or is a mixed solvent that includes at least one of these solvents.