Application as Matrix for Controlled Drug Release

One major challenge in the field of pharmacokinetics is to sustain the therapeutic level of a drug in body tissue (e.g. blood) as long as possible, during the entire length of treatment. 

The side effects always occur with high doses and are proportional to its concentration in the blood. Evidently, the initial high concentration (just after traditional drug administration) of the drug in the blood leads to unwanted 

The most convenient controlled release system (CRS) consists of the drug enclosed in a customized matrix, which releases the drug at a predetermined rate, to maintain the therapeutic level of the drug in blood plasma or in the area of the intended tissue. 

Because of low cost and ease of fabrication, one common way of obtaining the controlled release of a drug is by enclosing it in a hydrophobic matrix (such 

Principles of polymerization (3 edition), John Wiley Sons, New York, 2002. 

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