title: Amphiphilic poly(D,L-lactic acid)/poly(ethylene glycol)/poly(D,L-lactic acid) nanogels for controlled release of hydrophobic drugs.
abstract: Photocrosslinked nanogels with a hydrophobic core and hydrophilic shell are successfully fabricated with the goal of obtaining a biocompatible and biodegradable drug carrier for hydrophobic anticancer drugs. These nanogels are composed of amphiphilic triblock copolymers, poly(D,L-lactic acid)/poly(ethylene glycol)/poly(D,L-lactic acid) (PLA-PEG-PLA), with acrylated groups at the end of the PLA segments. The copolymers are synthesized by ring-opening polymerization and possess a low CMC (49.6 mg x L(-1)), which easily helps to form micelles by self-assembly. The acrylated end groups allow the micelles to be photocrosslinked by ultraviolet irradiation, which turn the micelles into nanogels. These nanogels exhibit excellent stability as a suspension in aqueous media at ambient temperature as compared to the micelles. Moreover, the size of the nanogels is easily manipulated in a range of 150 to 250 nm by changing the concentration of crosslinkers, e.g., ethylene glycol dimethacrylate, and ultraviolet light irradiation time. The nanogels achieve a high encapsulation efficiency and offer a steady and long-term release mechanism for the hydrophobic anticancer drug, CPT. It shows that these nanogels are useful for a hydrophobic anticancer drug-carrier system. [pictures: see text] Formation of the PLA-PEG-PLA nanogels.
authors.affiliation: Department of Chemical Engineering, National Tsing Hua University, 101, Section 2 Kuang Fu Road, Hsinchu 300, Taiwan.
authors.forename: Wen-Chuan
authors.initials: WC
authors.lastname: Lee
authors.forename: Yuan-Chung
authors.initials: YC
authors.lastname: Li
authors.forename: I-Ming
authors.initials: IM
authors.lastname: Chu
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000737:chemistry; D002166:Camptothecin / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D008823:Micelles; D015394:Molecular Structure; D000080385:Nanogels; D011091:Polyesters / Q000138:chemical synthesis* / Q000737:chemistry; D011092:Polyethylene Glycols / Q000138:chemical synthesis* / Q000737:chemistry*; D011094:Polyethyleneimine / Q000737:chemistry*; D012995:Solubility; D014867:Water
chemical_list: D001672:Biocompatible Materials; D008823:Micelles; D000080385:Nanogels; D011091:Polyesters; C413692:polyethylene glycol polyethyleneimine nanogel; C507889:polylactide-polyethylene glycol-polylactide; D014867:Water; D011092:Polyethylene Glycols; D011094:Polyethyleneimine; D002166:Camptothecin