Patent ID: 8702941

Claim:
A method for analyzing hemoglobin in a sample solution containing hemoglobin by electrophoresis, the method comprising: performing electrophoresis of the sample solution under conditions in which an add substance having two or more carboxyl groups is present in an electrophoresis solution having a pH of 4.5 to 6, wherein the electrophoresis solution comprises a buffer and a separation enhancing agent, the separation enhancing agent comprising the acid substance; a difference obtained by subtracting a second acid dissociation constant (pK a2 A) of the acid substance in the separation enhancing agent from an acid dissociation constant (pK a B) of the buffer responsible for its buffer capacity is 0.2 or more; separation of hemoglobin by the electrophoresis is carried out in a separation capillary channel; and at least two of the carboxyl groups of the acid substance each have an acid dissociation constant (pK a1 A and pK a2 A) lower than a pH of the electrophoresis solution at the time of analysis, wherein the acid substance (A) is L-glutamic acid or (B) comprises a cyclohexane ring or (C) comprises two or more carboxyl groups where one of the carboxyl groups has a second dissociation constant (pK a2 ) in the range of 2 to 4.