ABSTRACT
A buffer can be defined as a solution whose properties allow it to resist changes in acidity or basicity when modest increments of acid or base are added to that solution. Buffers contain an amount of dissolved weak acid or base and the corresponding salt of that weak acid or base, and achieve their function by varying the ratio of the ionic species as additional acidic or basic components are added. This entry discusses the role of buffering agents in drug characterization studies and reviews the range of pharmaceutically acceptable buffer systems across useful pH values.
