title: Investigation into the mechanism by which cyclodextrins influence transdermal drug delivery.
abstract: The objective of this study was to investigate the mechanism by which hydroxypropyl-beta-cyclodextrin (HPCD) increases transdermal permeation. Hairless mouse skin was pretreated with HPCD solutions for up to 4 h. After removing the HPCD, corticosteroid-containing suspensions were applied and the transdermal flux and skin accumulation of two model drugs were investigated. After pretreatment, changes to the stratum corneum endothermic melting transitions were determined as an indication of HPCD-induced lipid disorganization. Results demonstrated that HPCD pretreatment had no significant effect on the transdermal permeation or skin accumulation of the model corticosteroids. These findings suggest that HPCD functions to enhance the apparent solubility of the drug in the formulation, thus increasing transdermal permeation rather than extracting lipids from the skin.
authors.affiliation: College of Pharmacy, University of New Mexico, Albuquerque, New Mexico 87131, USA.
authors.forename: Clifford L
authors.initials: CL
authors.lastname: Kear
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.forename: Donald A
authors.initials: DA
authors.lastname: Godwin
authors.forename: Linda A
authors.initials: LA
authors.lastname: Felton
mesh_terms: D000073738:2-Hydroxypropyl-beta-cyclodextrin; D000279:Administration, Cutaneous; D000818:Animals; D005079:Excipients / Q000494:pharmacology*; D005938:Glucocorticoids / Q000737:chemistry / Q000493:pharmacokinetics*; D006854:Hydrocortisone / Q000737:chemistry / Q000493:pharmacokinetics; D051379:Mice; D008812:Mice, Hairless; D010539:Permeability; D044367:Phase Transition; D012867:Skin / Q000187:drug effects / Q000378:metabolism; D012869:Skin Absorption; D012995:Solubility; D013816:Thermodynamics; D013997:Time Factors; D044366:Transition Temperature; D014221:Triamcinolone / Q000737:chemistry / Q000493:pharmacokinetics; D047392:beta-Cyclodextrins / Q000494:pharmacology*
chemical_list: D005079:Excipients; D005938:Glucocorticoids; D047392:beta-Cyclodextrins; D000073738:2-Hydroxypropyl-beta-cyclodextrin; D014221:Triamcinolone; D006854:Hydrocortisone