title: An in vitro study on the photosensitivity of 5-aminolevulinic acid conjugated gold nanoparticles.
abstract: BACKGROUND
  In this study, the photosensitivity of 5-aminolevulinic acid (5-ALA) conjugated gold nanoparticles (conjugate) has been investigated on the MeL-Rm cell line.
  
  
  METHODS
  After culture and proliferation of the Mel-Rm cell line, cell toxicity and the suitable cell incubation time of the conjugate were determined. Photosensitivity of the conjugate and free 5-ALA was then studied in optical doses of 20, 40, 60 and 80 J/cm(2) while light irradiation was applied by a He-Ne laser.
  
  
  RESULTS
  A 4-h time interval was determined as the optimum incubation time for 5-ALA and the conjugate. PpIX induction into the cells showed a significant increase after incubation with the conjugate in comparison to 5-ALA alone. Also, the conjugate resulted in a two times higher cell death rate compared to free 5-ALA.
  
  
  CONCLUSIONS
  The conjugate can be used as an appropriate delivery agent for 5-ALA and provide efficient cell destruction during PDT.
authors.affiliation: Department and Research Center of Medical Physics, Babol University of Medical Sciences, Babol, Iran. Electronic address: Mehr_055@yahoo.com.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Mohammadi
authors.forename: Ameneh
authors.initials: A
authors.lastname: Sazgarnia
authors.forename: Omid
authors.initials: O
authors.lastname: Rajabi
authors.forename: Samaneh
authors.initials: S
authors.lastname: Soudmand
authors.forename: Habibollah
authors.initials: H
authors.lastname: Esmaily
authors.forename: Hamid Reza
authors.initials: HR
authors.lastname: Sadeghi
mesh_terms: D000622:Aminolevulinic Acid / Q000008:administration & dosage* / Q000737:chemistry; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D006046:Gold / Q000008:administration & dosage* / Q000737:chemistry; D006801:Humans; D008545:Melanoma / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology*; D053769:Nanocapsules / Q000008:administration & dosage* / Q000737:chemistry; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000008:administration & dosage; D011836:Radiation Tolerance / Q000187:drug effects / Q000528:radiation effects*; D016896:Treatment Outcome
chemical_list: D053769:Nanocapsules; D017319:Photosensitizing Agents; D006046:Gold; D000622:Aminolevulinic Acid
keywords: 5-Aminolevulinic acid; Gold nanoparticle (GNP); Mel-Rm cell line.; Photodynamic therapy (PDT); Protoporphyrin IX (PpIX)