Bis-Tris is a zwitterionic buffer; an amine buffer similar to Tris Hydrochloric acid that exhibits only a very small shift in dissociation constant with respect to temperature. It is structurally analogous to the the Good buffers that were developed to provide buffers in the pH range of 6.15 - 8.35…

Bis-Tris is zwitterionic buffer, an amine buffer similar to Tris. It exhibits only a very small shift in dissociation constant with respect to temperature. Hydrochloric acid can be used to adjust pH for a Bis-Tris buffer to the desired pH.