title: Photodynamic therapeutic activity of indocyanine green entrapped in polymeric nanoparticles.
abstract: BACKGROUND
  Photodynamic therapy (PDT) is a therapeutic modality involving the use of a photosensitizer agent activated by light of appropriate wavelength to selectively destroy tumor cells. Indocyanine green (ICG) is a promising photosensitive agent for PDT of tumor cells. The main disadvantage of using ICG in PDT is the instability of ICG in aqueous solutions. Encapsulating ICG dye in a biocompatible matrix based on PEBBLE technology showed an improvement of aqueous stability comparing with free ICG dye. The main objective of this study is to investigate the photodynamic effect of ICG-ormosil PEBBLEs on two different cell lines: human breast adenocarcinoma cells (MCF-7) and hepatocellular carcinoma cells (HepG2).
  
  
  METHODS
  ICG-embedded ormosil PEBBLEs were synthesized based on a sol-gel process, and characterized by transmission electron microscopy and other fluorescence tests. The cell viability was evaluated by MTT and trypan blue assays. Apoptosis, necrosis, and DNA damage (comet assay), were evaluated by fluorescence microscopic tests.
  
  
  RESULTS
  The results declared that ICG-ormosil PEBBLEs and free ICG both have the same cytotoxic and phototoxic effect on MCF-7 and HepG2 cell lines, where the apoptotic mode of cell death is preferentially occurred in case of PDT using ICG-ormosil PEBBLEs. Both ICG and ICG-ormosil PEBBLEs induced DNA damage after laser exposure. These results would suggest that entrapping ICG in Polymeric nanoparticles forming ICG-ormosil PEBBLEs improve the aqueous stability of the photosensitizer and in the same time retain its photodynamic activity, suggesting that it is preferred to use ICG-ormosil PEBBLEs instead of free ICG dye.
authors.affiliation: Department of Medical Biochemistry, National Research Center, Cairo, Egypt.
authors.forename: Sherien M
authors.initials: SM
authors.lastname: El-Daly
authors.forename: Amira M
authors.initials: AM
authors.lastname: Gamal-Eldeen
authors.forename: Mona A M
authors.initials: MA
authors.lastname: Abo-Zeid
authors.forename: Ibrahim H
authors.initials: IH
authors.lastname: Borai
authors.forename: Hanaa A
authors.initials: HA
authors.lastname: Wafay
authors.forename: Abdel-Rahman B
authors.initials: AR
authors.lastname: Abdel-Ghaffar
mesh_terms: D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D056945:Hep G2 Cells; D006801:Humans; D007208:Indocyanine Green / Q000737:chemistry* / Q000627:therapeutic use; D061986:MCF-7 Cells; D053769:Nanocapsules / Q000737:chemistry / Q000627:therapeutic use*; D009374:Neoplasms, Experimental / Q000188:drug therapy* / Q000473:pathology*; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000737:chemistry / Q000627:therapeutic use; D011108:Polymers / Q000737:chemistry*; D012833:Siloxanes / Q000737:chemistry; D016896:Treatment Outcome
chemical_list: D053769:Nanocapsules; D017319:Photosensitizing Agents; D011108:Polymers; D012833:Siloxanes; C510784:ormosil; D007208:Indocyanine Green