アミノ酸の経皮吸収性 (第2報)
スポンサーリンク
概要
- 論文の詳細を見る
Amino acids are amphoteric electrolytes and water-soluble compounds. In general, a water-soluble drug such as amino acid shows low skin permeability due to the barrier effects of stratum corneum. We had previously reported that skin permeability of L-phenylalanine improved by approximately 71∼220 times upon the use of its ester derivatives. In this paper, we selected L-phenylalanine as a model compound and investigated skin permeability of its amide derivatives. And also we investigated the correlation between chemical modification of L-phenylalanine and its skin permeability. Excised hairless mouse skin was mounted between the donor and the receptor chamber of a skin-permeation apparatus. The compound that permeated through the skin was analyzed by HPLC. The permeability of L-phenylalanine and its derivatives was calculated from the accumulated amount of the sample in the receptor chamber for specific time period. The results showed that the amide permeated through the skin without its structural change and the permeation rate of amide derivatives were almost the same as that of L-phenylalanine. The correlation between chemical modification of L-phenylalanine and its skin permeability showed that the esterification of carboxyl group improved its skin permeability and the amidation of amino group or carboxyl group reduced the permeability. The results indicated that the amidation of L-phenylalanine did not improve its permeability through the skin and that its amide derivatives might not be a good candidate as a prodrug of L-phenylalanine. On the other hand, since the esterification of L-phenylalanine improved its permeability through the skin, its ester derivatives could be a prodrug of L-phenylalanine.
- 1996-09-10