Magnetophoresis in combination with chemical enhancers for transdermal drug delivery

Abstract

Purpose: The objective of the present work was to investigate the effect of combination of a novel physical permeation enhancement technique, magnetophoresis with chemical permeation enhancers on the transdermal delivery of drugs.

Methods: The in vitro drug transport studies were carried out across the freshly excised abdominal skin of Sprague-Dawley rats using transdermal patch systems (magnetophoretic and non-magnetophoretic) of lidocaine hydrochloride (LH). LH gel prepared using hydroxypropyl methylcellulose (HPMC) was spread over the magnets as a thin layer. To investigate the effect of chemical permeation enhancers, menthol, dimethyl sulfoxide, sodium lauryl sulfate and urea (5% w/v) were incorporated in the gels prior to loading on the patch system.

Results: The flux of lidocaine from magnetophoretic patch was ~3-fold higher (3.07 ± 0.43 µg/cm²/h) than that of the control (non-magnetophoretic patch) (0.94 ± 0.13 µg/cm²/h). Incorporation of chemical permeation enhancers in the gel enhanced the magnetophoretic delivery flux by ~4 to 7-fold.

Conclusions: The enhancement factor due to combination of chemical permeation enhancer was additive and not synergistic. Mechanistic studies indicated that magnetophoresis mediated drug delivery enhancement was via appendageal pathway.

Keywords::

• Transdermal patch system
• magnetophoresis
• chemical permeation enhancers
• lidocaine hydrochloride
• in vitro drug permeation

Acknowledgments

The authors would also like to thank 3M Drug Delivery Systems (St. Paul, MN) for providing gift samples of 3M^™ 9773 adhesive Foam Tape.

Declaration of interest

The project described was supported by Grant Number 5P20RR021929 from the National Center for Research Resources. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center for Research Resources or the National Institutes of Health. This project was also partially supported funded by Grant Number HD061531A from Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD).