title: Use of osmotically active agents to alter optical properties of tissue: effects on the detected fluorescence signal measured through skin.
abstract: OBJECTIVE
  Hyper-osmotic chemical agents were used to study the effects of transient tissue scattering on the remitted fluorescence emission intensity from a target placed under a tissue sample.
  
  
  METHODS
  A fluorescent film was placed underneath in vitro and in vivo samples of hamster skin, and the remitted fluorescent signal traveling to the tissue surface was monitored over time as the tissue was treated with an osmotically active agent.
  
  
  RESULTS
  The detected fluorescent signal increased as the scattering in tissue samples was substantially reduced. The increase was greater for dimethyl sulfoxide than glucose or glycerol. It was not statistically different between in vivo skin and in vitro skin.
  
  
  CONCLUSIONS
  The study shows how chemical agents can be used to improve the detected signal for a specific optical application. It could be useful in a number of optical therapeutic and diagnostic applications that can benefit from an increase in the penetration depth of light.
authors.affiliation: The Biomedical Engineering Program, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: G
authors.initials: G
authors.lastname: Vargas
authors.forename: K F
authors.initials: KF
authors.lastname: Chan
authors.forename: S L
authors.initials: SL
authors.lastname: Thomsen
authors.forename: A J
authors.initials: AJ
authors.lastname: Welch
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D006224:Cricetinae; D004121:Dimethyl Sulfoxide / Q000493:pharmacokinetics*; D005453:Fluorescence; D005947:Glucose / Q000493:pharmacokinetics*; D005990:Glycerol / Q000493:pharmacokinetics*; D066298:In Vitro Techniques; D008647:Mesocricetus; D008853:Microscopy; D055095:Optics and Photonics; D009995:Osmosis / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012542:Scattering, Radiation; D012867:Skin / Q000187:drug effects / Q000473:pathology; D012879:Skin Physiological Phenomena / Q000187:drug effects*
chemical_list: D005947:Glucose; D005990:Glycerol; D004121:Dimethyl Sulfoxide