Patent ID: 8163471

Claim:
A reagent kit for measuring basophils and nucleated red blood cells, which comprises a solution comprising a cationic surfactant and an aromatic organic acid, wherein the cationic surfactant hemolyzes erythrocytes, and gives damage to a cell membrane of leukocytes to such an extent that a fluorescent dye can permeate therethrough, the cationic surfactant is selected from the group consisting of a quaternary ammonium salt type and a pyridinium salt, and wherein pH of the solution comprising the cationic surfactant is 2.0 to 4.5, and a solution comprising at least one kind of fluorescent dye selected from the group consisting of the following general formulae (I) and (II), the general formula (I): wherein R 1 and R 2 are identical or different and each represents an alkyl group which has 1-4 carbon atoms; provided that when R 3 , R 4 , R 5 and R 6 are identical or different and each represents a hydrogen atom or an alkyl group; and X − represents an anion, and the general formula (II): wherein R 7 and R 8 are identical or different and each represents an alkyl group optionally having an acidic group; R 9 , R 10 , R 11 and R 12 are identical or different and each represents a hydrogen atom or an acidic group, provided that any one of R 7 to R 12 has an acidic group; an acidic group which can be present on R 7 to R 12 may form a salt, provided that any one of acidic groups which can be present on R 7 to R 12 is a group which has released a proton.