Reciprocating Dissolution Tester - Apparatus 3

The Reciprocating Dissolution Tester (USP Apparatus 3), described in USP <711>, is a dissolution testing device that operates using a vertical reciprocating motion. In this apparatus, the dosage form is placed inside mesh-ended cylindrical cells, which move up and down between vessels containing different dissolution media.

Apparatus 3 is particularly suitable for modified-release, extended-release, and delayed-release dosage forms, as it allows simulation of physiological gastrointestinal conditions, including changes in pH and residence time. The system provides precise control of temperature (37 ± 0.5 °C), dipping speed (cycles per minute), and media sequence, making it especially useful for formulation development and comparative dissolution profiling.