Amine-Citrate Buffers for <i>p</i>H Control in Starch Gel Electrophoresis

Abstract

Amine-citrate buffer systems for pH control in starch gel electrophoresis gave good resolution of some dehydrogenase isozymes. The pK's of three new amine buffers, N-(3-aminopropyl)-morpholine, pK 2 25 C, 6.12; N-(3-aminopropyl)-diethanolamine, pK 2 25 C, 6.90; and 1,3-bis(dimethylamino)-2-propanol, pK 2 25 C, 7.55, were determined at 5 C intervals in the range 10–40 C. These compounds, together with N, N-bis(2-hydroxyethyl)iminotris(hydroxymethyl)methane (bis-Tris) and tris-(hydroxymethyl)-methylamine(Tris), provide a series of amine buffers with pK's at 0.5 unit intervals in the pH range 6.1–8.1.