Rate-controlling membrane

Alza Corp. has also developed an iatrauteriae device, Progestasert, designed to release progesterone [57-83-0] by diffusion through a rate-controlling membrane for up to one year. The dmg reservoir is built into a T-shaped device that is inserted intravaginaHy (15). 

Compatibility and safety for topical delivery systems are addressed in the same manner as for topical drug products. Performance and quality control should be addressed for the rate-controlling membrane. Appropriate microbial limits should be established and justified for each delivery system. Microbiological standards are under development therefore, the review division for a specific application should be consulted. 

An example of such a reservoir matrix system is a rate-controlling membrane coated solid solution beads comprising (1) a hydrophobic long-chain fatty acid or ester material (2) a surfactant and... 

Other polymeric materials commonly used as non-porous, rate-controlling membranes are given in Table 4.2. 

The sustained release of artificial tears has been achieved by a hydroxypropylcel-lulose polymer insert [77], However, the best known application of diffusional therapy in the eye, Ocusert-Pilo, as shown in Figure 7, is a relatively simple structure with two rate-controlling membranes surrounding the drug reservoir containing... 

Membrane-moderated patches have been utilized in many FDA-approved transdermal patches such as Duragesic, Transderm Scop, and Catapress TTS. This type of patch utilizes a rate-controlling membrane to precisely control the release of... 

---