title: Liquid chromatography assay for 5-aminolevulinic acid: application to in vitro assessment of skin penetration via Dermaportation.
abstract: The purpose of the present study was to develop a reverse-phase high performance liquid chromatographic (HPLC) assay for quantifying 5-aminolevulinic acid (ALA). The assay was applied to study the skin permeation of ALA and the influence of a novel skin penetration enhancement technology. Separation was achieved utilizing a Phenomenex Jupiter C(18) column following fluorescence derivatization with fluorescamine. The assay was linear (r(2)>0.99) with a minimum limit of quantitation of 400 ng/mL. The inter- and intraday variation was 1.6 and 0.9% at the lower end of the linear range and 1.5 and 1.9% at the upper end, respectively. The HPLC assay and fluorescence derivatization procedure is sensitive, simple, rapid, accurate and reproducible and offers advantages with regard to stability of ALA in comparison to other fluorescence derivatization methods. Results from the preliminary skin permeation study demonstrated substantial skin penetration of ALA only when applied with Dermaportation as a skin penetration enhancement device.
authors.affiliation: School of Pharmacy, Curtin University of Technology, Perth, WA 6845, Australia.
authors.forename: Sarika
authors.initials: S
authors.lastname: Namjoshi
authors.forename: Rima
authors.initials: R
authors.lastname: Caccetta
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Edwards
authors.forename: Heather A E
authors.initials: HA
authors.lastname: Benson
mesh_terms: D000622:Aminolevulinic Acid / Q000008:administration & dosage / Q000032:analysis* / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid; D005456:Fluorescent Dyes / Q000737:chemistry; D015203:Reproducibility of Results; D012867:Skin / Q000737:chemistry*; D012869:Skin Absorption; D013050:Spectrometry, Fluorescence
chemical_list: D005456:Fluorescent Dyes; D000622:Aminolevulinic Acid