title: Ultrasound-triggered drug release and enhanced anticancer effect of doxorubicin-loaded poly(D,L-lactide-co-glycolide)-methoxy-poly(ethylene glycol) nanodroplets.
abstract: A novel ultrasound-responsive doxorubicin (DOX)-loaded nanoparticulate system was prepared in this study. The DOX-loaded polymeric micelles were first prepared using poly(D,L-lactide-co-glycolide)-methoxy-poly(ethylene glycol) (PLGA-mPEG) with a high encapsulation efficiency of 89.2%. After filling with perfluoropentane (boiling point 29 °C), the micelles were transformed into nanodroplets that were stable as a result of the PEG shell. The nanodroplets were transformed into nanobubbles at 37 °C, and little drug was released if no ultrasound was exerted. Ultrasound-triggered drug release, with pH dependency, was shown. The DOX release percentage was 9.59% at pH 6.5 (also appeared in tumor) and only 2.22% at pH 7.4 after sonicating for 0.5 min at 37 °C. The tumor inhibitory rate of Group III (DOX-loaded nanodroplets combined with ultrasound) was 84.3%, more than that of Group II (DOX-loaded nanodroplets), which was 60.4%. Moreover, the nanodroplets showed much lower toxicity than free drugs. The novel nanodroplets could be a promising anticancer drug delivery system.
authors.affiliation: Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, Beijing, China.
authors.forename: Lina
authors.initials: L
authors.lastname: Du
authors.forename: Yiguang
authors.initials: Y
authors.lastname: Jin
authors.forename: Wenying
authors.initials: W
authors.lastname: Zhou
authors.forename: Jingyu
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000818:Animals; D004317:Doxorubicin / Q000494:pharmacology*; D004337:Drug Carriers / Q000737:chemistry / Q000494:pharmacology*; D016503:Drug Delivery Systems; D005260:Female; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000737:chemistry / Q000494:pharmacology*; D051379:Mice; D008823:Micelles; D053758:Nanoparticles; D009374:Neoplasms, Experimental / Q000188:drug therapy*; D011092:Polyethylene Glycols / Q000737:chemistry / Q000494:pharmacology; D011100:Polyglycolic Acid / Q000737:chemistry / Q000494:pharmacology*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D014465:Ultrasonics / Q000379:methods*
chemical_list: D004337:Drug Carriers; D008823:Micelles; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D011092:Polyethylene Glycols; D004317:Doxorubicin