Heat Denaturation Test for Unstable Hemoglobin, with a Note on Its Application to Hemoglobin Survey in Japan

　Dacie's heat denaturation test was modified in order to get a practical procedure for detecting unstable hemoglobin in hemolysates. For the purpose of screening a centrifugation method was devised : hemolysate, phosphate buffer solution (0.1 M, pH 7.4), and zinc chloride solution were mixed in equal proportions (0.2 ml each) in a test tube and transferred to a capillary tube (0.3 × 12 cm). The capillary tube was sealed at one end by fusion in a flame of a burner so that the mixture might be contained safely in it, warmed at 50℃ for 60 minutes, and then centrifuged at 3000 rpm (1700 G) for 5 minutes to read the amount of precipitate sedimented at the bottom in terms of the percentage of the total co1umn of the mixture. A reading larger than 3.5 per cent is suggesive of the presence of unstable hemoglobin in hemolysate. Such a hemolysate should be examined by spectrophotometric method to connrm the result. Namely, hemolysate (30 μl) was mixed with warm (55℃) phosphate buffer solution (0.1 M, pH 7.4