Controlled permeation of lidocaine hydrochloride using a smart drug delivery system

Transdermal administration might be an interesting alternative to current routes of administration. It is non-invasive, avoids gastric side effects, and improves bioavailability of the molecules. However, due to the low permeability of the stratum corneum, a permeation enhancement strategy is required to make a large number of molecules suitable to this mode of administration. To overcome those limitations and deliver controlled drugs, a smart transdermal drug delivery system is designing. This paper focusses on the study of transdermal iontophoresis permeation of lidocaine hydrochloride (2%, w/w) across pig ear skin. In vitro iontophoresis experiments were conducted using Franz diffusion cells. Anodal iontophoresis was applied for 30 minutes at different current densities. Samples (1 mL) were withdrawn every 30 minutes from the receptor compartment and replaced with a fresh buffer and then analyzed using High Performance Liquid Chromatography (HPLC). Results highlight the relationship between current density, time of stimulation, and amount of lidocaine permeated.