Geometrical features such as shape and surface area of a drug-releasing matrix affect drug release kinetics by changing diffusion rates across the matrix, lengthening the diffusion pathway through drug–matrix composition or simply presenting a different surface area to the dissolution medium. Such variables can change during the dissolution process, due to drug depletion or erosion or dissolution of release-modifying components. Such phenomena can help the development of novel dosage units since they present opportunities to capitalize on shape and surface effects designing a matrix that optimally delivers drug at the required rate. The historical development and state-of-the-art of geometrically designed dosage forms are presented in this chapter.
Geometric Release Systems: Principles, Release Mechanisms, Kinetics, Polymer Science, and Release-Modifying Material
COLOMBO, Gaia;
2011
Abstract
Geometrical features such as shape and surface area of a drug-releasing matrix affect drug release kinetics by changing diffusion rates across the matrix, lengthening the diffusion pathway through drug–matrix composition or simply presenting a different surface area to the dissolution medium. Such variables can change during the dissolution process, due to drug depletion or erosion or dissolution of release-modifying components. Such phenomena can help the development of novel dosage units since they present opportunities to capitalize on shape and surface effects designing a matrix that optimally delivers drug at the required rate. The historical development and state-of-the-art of geometrically designed dosage forms are presented in this chapter.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
