S Lee1, N Kollias, D J McAuliffe, T J Flotte, A G Doukas. 1. Wellman Laboratories of Photomedicine, Massachusetts General Hospital, Department of Dermatology, Harvard Medical School, Boston 02114, USA. lee@helix.mgh.harvard.edu
Abstract
PURPOSE: Assess the feasibility of in vivo topical drug delivery in humans with a single photomechanical wave. METHODS: Photomechanical waves were generated with a 23 nsec Q-switched ruby laser. In vivo fluorescence spectroscopy was used as an elegant non-invasive assay of transport of 5-aminolevulinic acid into the skin following the application of a single photomechanical wave. RESULTS: The barrier function of the human stratum corneum in vivo may be modulated by a single (110 nsec) photomechanical compression wave without adversely affecting the viability and structure of the epidermis and dermis. Furthermore, the stratum corneum barrier always recovers within minutes following a photomechanical wave. The application of the photomechanical wave did not cause any pain. The dose delivered across the stratum corneum depends on the peak pressure and has a threshold at approximately 350 bar. A 30% increase in peak pressure, produced a 680% increase in the amount delivered. CONCLUSIONS: Photomechanical waves may have important implications for transcutaneous drug delivery.
PURPOSE: Assess the feasibility of in vivo topical drug delivery in humans with a single photomechanical wave. METHODS: Photomechanical waves were generated with a 23 nsec Q-switched ruby laser. In vivo fluorescence spectroscopy was used as an elegant non-invasive assay of transport of 5-aminolevulinic acid into the skin following the application of a single photomechanical wave. RESULTS: The barrier function of the human stratum corneum in vivo may be modulated by a single (110 nsec) photomechanical compression wave without adversely affecting the viability and structure of the epidermis and dermis. Furthermore, the stratum corneum barrier always recovers within minutes following a photomechanical wave. The application of the photomechanical wave did not cause any pain. The dose delivered across the stratum corneum depends on the peak pressure and has a threshold at approximately 350 bar. A 30% increase in peak pressure, produced a 680% increase in the amount delivered. CONCLUSIONS: Photomechanical waves may have important implications for transcutaneous drug delivery.
Authors: Grace Tan; Peng Xu; Louise B Lawson; Jibao He; Lucia C Freytag; John D Clements; Vijay T John Journal: J Pharm Sci Date: 2010-02 Impact factor: 3.534