title: Effect of lactic acid and iontophoresis on drug permeation across rabbit ear skin.
abstract: The aim of this paper was to explore the efficacy of lactic acid as permeation enhancer for drug molecules across the skin. Three model permeants were chosen: acetaminophen (non-ionized), buspirone hydrochloride (cationic drug) and ibuprofen lysine (anionic drug). We also explored the association of lactic acid and iontophoresis as a means of enhancing drug delivery. Permeation experiments were performed in vitro, using rabbit ear skin as barrier. The results obtained indicate that lactic acid has some effects on model drug permeation across the skin. The effect was more evident with the anionic drug ibuprofen. Cathodal intophoresis increased ibuprofen transport, but when lactic acid was associated with cathodal iontophoresis, a concentration-dependent reduction of ibuprofen iontophoretic flux was observed, probably for the competition by the co-ion. The application of electric current (anodal iontophoresis) to a solution of acetaminophen produced an increase in its transport, due to the presence of an electroosmotic contribution; however, the effect of the association of anodal iontophoresis and lactic acid produced no further enhancement.
authors.affiliation: Dipartimento Farmaceutico, University of Parma, Parco Area delle Scienze, 43100 Parma, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Sebastiani
authors.forename: S
authors.initials: S
authors.lastname: Nicoli
authors.forename: P
authors.initials: P
authors.lastname: Santi
mesh_terms: D000082:Acetaminophen / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics; D000287:Administration, Topical; D000818:Animals; D001682:Biological Availability; D002065:Buspirone / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics; D002463:Cell Membrane Permeability / Q000187:drug effects* / Q000502:physiology; D004353:Drug Evaluation, Preclinical / Q000379:methods; D004423:Ear / Q000473:pathology*; D005079:Excipients / Q000737:chemistry / Q000493:pharmacokinetics; D007052:Ibuprofen / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000378:metabolism / Q000493:pharmacokinetics; D007478:Iontophoresis / Q000379:methods*; D019344:Lactic Acid / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics*; D008239:Lysine / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000378:metabolism / Q000493:pharmacokinetics; D011817:Rabbits; D012869:Skin Absorption / Q000187:drug effects* / Q000502:physiology
chemical_list: D005079:Excipients; D019344:Lactic Acid; D000082:Acetaminophen; D008239:Lysine; C016106:solufenum; D002065:Buspirone; D007052:Ibuprofen