Increase of ibuprofen penetration through the skin by forming ion pairs with amino acid alkyl esters and exposure to the electromagnetic field.

A method of increasing the permeability of ibuprofen through the skin using a rotating magnetic field (RMF) is presented. This study evaluated whether 50 Hz RMF modifies ibuprofen's permeability through the skin. Ibuprofen and its structural modifications in the form of ibuprofenates of isopropyl esters of L-amino acids such as L-valine, L-phenylalanine, L-proline, and L-aspartic acid were used in the research. To this end, Franz cells with skin as membrane were exposed to 50 Hz RMF with 5% ibuprofen and its derivatives in an ethanol solution for 48 h. Following the exposures, the amount of penetrated compound was analysed. Regardless of the compound tested, a significant increase in drug transport through the skin was observed. The differences in the first 30 min of permeation are particularly noticeable. Furthermore, it was shown that using RMF increases the permeability of ibuprofen from 4 to 244 times compared to the test without the RMF. The greatest differences were observed for unmodified ibuprofen. However, it is noteworthy that the largest amounts of the active substance were obtained with selected modifications and exposure to RMF. The RMF may be an innovative and interesting technology that increases the penetration of anti-inflammatory and anti-ache drugs through the skin.