Application of sucrose fatty acid esters in transdermal therapeutic systems

Transdermal therapeutic systems (TTSs) were studied applying different sucrose fatty acid esters (SEs) as drug delivery agents. Matrix and membrane controlled TTSs were prepared and compared. Membrane was made from a methacrylic polymer (Eudragit (R) NE) of pH independent permeability which can achieve diffusion controlled drug liberation. Model drug was a water soluble beta-blocker, metoprolol, which has short biological half-life, so applying it in a TTS, the duration of its action could be prolonged. Sucrose fatty acid esters of different fatty acid chain lengths and consequently different hydrophilic-lipophilic balance (HLB) values were studied considering their effect on the metoprolol release from TTSs. Different mathematical models were applied for the evaluation of the release process. The results of the in vitro studies indicated that SEs of shorter fatty acid chain length and higher HLB value increased the amount of released drug about 10 times. SEs could be promising agents in transdermal therapeutic systems to control the drug release and cutaneous absorption. (c) 2006 Elsevier B.V. All rights reserved.