title: Preparation and characterization of CdSe/ZnS quantum dots encapsulated in poly(ethylene glycol)-b-poly(D,L-lactide) micelle nanoparticles.
abstract: The final goal of this study is to develop multi-functional organic/inorganic hybrid nanoparticles, which can be utilized as biomedical imaging probes and drug delivery carriers. As an initial step toward this goal, we encapsulated CdSe/ZnS quantum dots (QDs) into poly(ethylene glycol)-b-poly(D,L-lactide) (PEG-PLA) micelles using a solid dispersion method. The size and fluorescent intensity of QDs encapsulated in PEG-PLA micelles depended on the amount of incorporated QDs. For example, when the amount of QDs increased from 0.1 to 1.0 microg, the mean diameter increased from 24.2 +/- 6.0 to 211.2 +/- 6.5 nm and the fluorescent intensity changed from 10.2 +/- 1.0 to 469.9 +/- 15.6 (RFU). Stability studies showed that the size and zeta-potential (ZP) of QDs encapsulated in PEG-PLA micelles (QEMs) did not change significantly in response to a change in pH conditions or under a 10% serum condition. We also tested the cytotoxicity and cellular uptake of the QEMs. The viability of HeLa cells treated with micelles for 24 h was 80-100% in various concentration ranges of micelles. Confocal laser scanning microscopic images showed that the QEMs penetrated into the cells, particularly into the cytosolic compartments. Our results suggest that the QEMs may be a promising multi-functional nanocarrier for biomedical imaging and drug delivery.
authors.affiliation: Department of Bioengineering, College of Engineering, Hanyang University, Seoul 133-791, Korea.
authors.forename: Joohyeon
authors.initials: J
authors.lastname: Lee
authors.forename: Jeong Hyuk
authors.initials: JH
authors.lastname: Im
authors.forename: Kang Moo
authors.initials: KM
authors.lastname: Huh
authors.forename: Yong-kyu
authors.initials: YK
authors.lastname: Lee
authors.forename: Heungsoo
authors.initials: H
authors.lastname: Shin
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D004355:Drug Stability; D006367:HeLa Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D018613:Microscopy, Confocal; D053761:Nanocomposites / Q000737:chemistry*; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology; D017967:Zinc Compounds / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology
chemical_list: D019187:Cadmium Compounds; D008823:Micelles; D018036:Selenium Compounds; D017967:Zinc Compounds; C542623:monomethoxypolyethyleneglycol-polylactide block copolymer; D011092:Polyethylene Glycols; C058667:cadmium selenide; C044696:zinc selenide