title: Effect of applying modes of the polymer microneedle-roller on the permeation of L-ascorbic acid in rats.
abstract: Despite the advantages of drug delivery through skin, transdermal drug delivery is only used with a small subset of drugs because most compounds cannot cross the skin at therapeutically useful rates. Recently, a new concept known as microneedle was introduced and could be used to pierce effectively to deliver drugs using micron-sized needles in a minimally invasive and painless manner. In this study, the polymer microneedle-roller was fabricated so that it can be applied into the permeation of L-ascorbic acid. Moreover, a recent publication suggested the possibility of ascorbic acid 2-phosphate as a hair restorer; hence, this study was carried out to check the effect of L-ascorbic acid itself on the hair growing rate in rats according to the presence of various application frequencies of the polymer microneedle-roller. When the polymer microneedle-roller was applied nine times with four directions into rat's shaved skin, the permeation of L-ascorbic acid increased by 10.54-fold compared to that of the absence of the polymer microneedle-roller. The histological examination revealed that the skin pretreated with various application frequencies of the polymer microneedle-roller had more transport pathways. The faster hair growing phenomenon was observed in the presence of polymer microneedle-roller compared to the absence of the polymer microneedle-roller.
authors.affiliation: College of Pharmacy and Institute of Drug Research and Development, Chungnam National University, Daejeon 305-764, South Korea.
authors.forename: Sung-Kyun
authors.initials: SK
authors.lastname: You
authors.forename: Young-Wook
authors.initials: YW
authors.lastname: Noh
authors.forename: Hyoun-Hyang
authors.initials: HH
authors.lastname: Park
authors.forename: Manhee
authors.initials: M
authors.lastname: Han
authors.forename: Seung S
authors.initials: SS
authors.lastname: Lee
authors.forename: Sang-Chul
authors.initials: SC
authors.lastname: Shin
authors.forename: Cheong-Weon
authors.initials: CW
authors.lastname: Cho
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D000975:Antioxidants / Q000493:pharmacokinetics*; D001205:Ascorbic Acid / Q000493:pharmacokinetics*; D001692:Biological Transport; D002626:Chemistry, Pharmaceutical / Q000379:methods; D016503:Drug Delivery Systems; D009339:Needles; D010539:Permeability; D011108:Polymers / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D012869:Skin Absorption; D013678:Technology, Pharmaceutical / Q000379:methods
chemical_list: D000975:Antioxidants; D011108:Polymers; D001205:Ascorbic Acid