Effect of polyoxyethylene glycols (PEG) on properties of the matrix model of transdermal therapeutic system (TTS) with testosterone

Polyoxyethylene glycols (PEG) are nontoxic substances, which ones do not irritate the skin, therefore can be used as pharmaceutical excipients to differentiate the properties of various matrices. The effect of variable content and molecular mass of PEG in cellulose acetate matrices on the testosterone solubility, the rate of water sorption and the release rate of testosterone from the matrix model of TTS was studied. It may be concluded that the testosterone solubility in matrices, the rate of water sorption by systems and the pharmaceutical availability of drug can be regulated on a relatively wide scale independently of molecular mass by the amounts of PEGs incorporated into matrices. It was found that in all cases of triphase matrices the liberation process of terosterone was well correlated with Higuchi's equation. The rate of water sorption by PEG and matrices may be described by the equation Q = k square root of t.