title: Facile Layer-by-Layer Self-Assembly toward Enantiomeric Poly(lactide) Stereocomplex Coated Magnetite Nanocarrier for Highly Tunable Drug Deliveries.
abstract: A highly tunable nanoparticle (NP) system with multifunctionalities was developed as drug nanocarrier via a facile layer-by-layer (LbL) stereocomplex (SC) self-assembly of enantiomeric poly(l-lactic acid) (PLLA) and poly(d-lactic acid) (PDLA) in solution using silica-coated magnetite (Fe3O4@SiO2) as template. The poly(lactide) (PLA) SC coated NPs (Fe3O4@SiO2@-SC) were further endowed with different stimuli-responsiveness by controlling the outermost layer coatings with respective pH-sensitive poly(lactic acid)-poly(2-dimethylaminoethyl methacrylate) (PLA-D) and temperature-sensitive poly(lactic acid)-poly(N-isopropylacrylamide) (PLA-N) diblock copolymers to yield Fe3O4@SiO2@SC-D and Fe3O4@SiO2@SC-N NPs, respectively, while the superparamagnetic properties of Fe3O4 were maintained. TEM images show a clearly resolved core-shell structure with a silica layer and sequential PLA SC co/polymer coating layers in the respective NPs. The well-designed NPs possess a size distribution in a range of 220-270 nm and high magnetization of 70.8-72.1 emu/g [Fe3O4]. More importantly, a drug release study from the as-constructed stimuli-responsive NPs exhibited sustained release profiles and the rates of release can be tuned by variation of external environments. Further cytotoxicity and cell culture studies revealed that PLA SC coated NPs possessed good cell biocompatibility and the doxorubicin (DOX)-loaded NPs showed enhanced drug delivery efficiency toward MCF-7 cancer cells. Together with the strong magnetic sensitivity, the developed hybrid NPs demonstrate a great potential of control over the drug release at a targeted site. The developed coating method can be further optimized to finely tune the nanocarrier size and operating range of pHs and temperatures for in vivo applications.
authors.affiliation: Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602, Singapore.
authors.forename: Zibiao
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Materials Science and Engineering, National University of Singapore , Singapore 117574, Singapore.
authors.forename: Du
authors.initials: D
authors.lastname: Yuan
authors.affiliation: Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602, Singapore.
authors.forename: Guorui
authors.initials: G
authors.lastname: Jin
authors.affiliation: Department of Materials Science and Engineering, National University of Singapore , Singapore 117574, Singapore.
authors.forename: Beng H
authors.initials: BH
authors.lastname: Tan
authors.affiliation: Department of Materials Science and Engineering, National University of Singapore , Singapore 117574, Singapore.|Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602, Singapore.
authors.forename: Chaobin
authors.initials: C
authors.lastname: He
mesh_terms: D016923:Cell Death / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002850:Chromatography, Gel; D004317:Doxorubicin / Q000494:pharmacology; D004337:Drug Carriers / Q000737:chemistry*; D016503:Drug Delivery Systems / Q000379:methods*; D065546:Drug Liberation; D004705:Endocytosis / Q000187:drug effects; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D006801:Humans; D057446:Hydrodynamics; D061986:MCF-7 Cells; D060328:Magnetic Phenomena; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D011091:Polyesters / Q000138:chemical synthesis / Q000737:chemistry*; D066244:Proton Magnetic Resonance Spectroscopy; D012822:Silicon Dioxide / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013237:Stereoisomerism; D014961:X-Ray Diffraction
chemical_list: D004337:Drug Carriers; D011091:Polyesters; C033616:poly(lactide); D012822:Silicon Dioxide; D004317:Doxorubicin; D052203:Ferrosoferric Oxide
keywords: drug delivery; layer-by-layer self-assembly; stereocomplex poly(lactide); stimuli-responsiveness; superparamagnetic Fe3O4