Colloidal gold production method and colloidal gold

摘要

It is an object of the present invention to provide a method for producing gold colloid having a targeted particle size, a sharp particle size distribution and a uniform and perfect spherical shape. The present invention relates to a method for producing gold colloid including a nucleation step of forming nuclear colloidal particles by adding a first reducing agent to a first gold salt solution; and a growth step of growing nuclear colloid by adding a second gold salt and a second reducing agent to the solution of the nuclear colloidal particles, characterized in that the growth step is performed at least once; a citrate is used as the first reducing agent and an ascorbate is used as the second reducing agent; and the addition of the ascorbate in the growth step is performed simultaneously with addition of the second gold salt. According to the method for producing gold colloid of the present invention, gold colloid having a sharp particle size distribution and a uniform and perfect spherical shape can be obtained.