What are diffusion controlled systems?

In diffusion controlled release systems, drugs are trapped in and released via diffusion through inert water-insoluble polymeric membranes (reservoir systems) or polymeric matrices (monolithic systems) [4, 7 – 9].

What are the characteristics of diffusion controlled release system?

What are the characteristics of Matrix diffusion-controlled release systems? Explanation: In this system, the drug is dispersed into an insoluble matrix of a rigid nonswellable hydrophobic material or swellable hydrophilic material. Materials such as insoluble plastic PVC and fatty acids are used as rigid matrix.

Which system works on diffusion controlled drug release?

The diffusion-controlled drug delivery systems are generally categorized into reservoir and matrix type delivery systems (Fig. 3). The reservoir type delivery systems are also regarded as the laminated matrix type delivery systems.

What are monolithic devices?

A device that is fabricated in a single piece; A device (i.e. circuit) that is operated at a single frequency or a single class of frequencies.

What are the different types of diffusion controlled systems?

Diffusion-controlled systems are classified into membrane-controlled and monolithic or matrix systems. In membrane-controlled systems, the drug is contained in the core as a reservoir and is covered by a thin polymeric membrane.

How do anisotropic structures affect diffusion coefficient?

Thus the anisotropic struct ure of the pores can a ffect the drug diffusion coefficient in different directions. preferential orientation which can result in anisotropi c behavior [33]. It has been established

What is diffusion front in a drug?

diffusion front. It separates the part of the matrix, where the drug is dissolved, from that of the undissolved (dispersed) drug and follows th e swelling front in its motion. When drug

What is the scientific rationale for controlled drug delivery systems?

The scientific rationale for the development of controlled drug delivery systems is to reduce the dose and frequency of dosage, reducing the fluctuations of blood plasma levels, patient compliance and adverse effects, and a reduction in the toxicity of the drug.