title: Zinc phthalocyanine-loaded PLGA biodegradable  nanoparticles for photodynamic therapy  in tumor-bearing mice.
abstract: Nanoparticles formulated from the biodegradable copolymer poly(lactic-coglycolic acid) (PLGA) were investigated as a drug delivery system to enhance tissue uptake, permeation, and targeting of zinc(II) phthalocyanine (ZnPc) for photodynamic therapy. Three ZnPc nanoparticle formulations were prepared using a solvent emulsion evaporation method and the influence of sonication time on nanoparticle shape, encapsulation and size distribution, in vitro release, and in vivo photodynamic efficiency in tumor-bearing mice were studied. Sonication time did not affect the process yield or encapsulation efficiency, but did affect significantly the particle size. Sonication for 20 min reduced the mean particle size to 374.3 nm and the in vitro release studies demonstrated a controlled release profile of ZnPc. Tumor-bearing mice injected with ZnPc nanoparticles exhibited significantly smaller mean tumor volume, increased tumor growth delay and longer survival compared with the control group and the group injected with free ZnPc during the time course of the experiment. Histopathological examination of tumor from animals treated with PLGA ZnPc showed regression of tumor cells, in contrast to those obtained from animals treated with free ZnPc. The results indicate that ZnPc encapsulated in PLGA nanoparticles is a successful delivery system for improving photodynamic activity in the target tissue.
authors: Pharmaceutical Technology Laboratory, Medical Laser Applications Department, National Institute of Laser Enhanced Science, Cairo University, Cairo, Egypt. mahafmali@hotmail.com
authors: Maha
authors: M
authors: Fadel
authors: Kawser
authors: K
authors: Kassab
authors: Doa Abdel
authors: DA
authors: Fadeel
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D002286:Carcinoma, Ehrlich Tumor / Q000188:drug therapy* / Q000473:pathology; D016503:Drug Delivery Systems; D005260:Female; D007211:Indoles / Q000008:administration & dosage*; D054833:Isoindoles; D019344:Lactic Acid; D051379:Mice; D008855:Microscopy, Electron, Scanning; D053769:Nanocapsules / Q000737:chemistry / Q000648:ultrastructure; D009942:Organometallic Compounds / Q000008:administration & dosage*; D010316:Particle Size; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000008:administration & dosage*; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D017967:Zinc Compounds
chemical_list: D001672:Biocompatible Materials; D007211:Indoles; D054833:Isoindoles; D053769:Nanocapsules; D009942:Organometallic Compounds; D017319:Photosensitizing Agents; D017967:Zinc Compounds; C052159:Zn(II)-phthalocyanine; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid