Self-assembly of phospholipid-PEG coating on nanoparticles through dual solvent exchange.

Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, United States.
Nano Letters (Impact Factor: 12.94). 08/2011; 11(9):3720-6. DOI: 10.1021/nl201978c
Source: PubMed

ABSTRACT We coated nanoparticles including iron oxide nanoparticles and quantum dots with phospholipid-PEG using the newly developed dual solvent exchange method and demonstrated that, compared with the conventional film hydration method, the coating efficiency and quality of coated nanoparticles can be significantly improved. A better control of surface coating density and the amount of reactive groups on nanoparticle surface is achieved, allowing conjugation of different moieties with desirable surface concentrations, thus facilitating biomedical applications of nanoparticles.

  • [Show abstract] [Hide abstract]
    ABSTRACT: Phospholipids with tethered poly(ethylene glycol) chains (PL-PEGs) offer efficient, noncovalent dispersion of carbon nanotubes (CNTs). Important questions concern the relation between micellar and CNT-assembled PL-PEG structures, and the influence of PEG length on assembly and dispersion. We explore these questions here via coarse-grained molecular dynamics simulation. Employing two representative CNT diameters and a range of PEG molecular weights, we find (i) PL-PEG aggregation number to vary inversely with PEG chain length, consistent with recent experiments, (ii) an assembled morphology to vary from micellar-like to monolayer-like, depending on PEG chain length and CNT diameter, (iii) micellar coatings to result in greater CNT dispersion ability, with a higher barrier for interparticle aggregation (84 kJ/mol) compared to monolayer coatings (60 kJ/mol), and (iv) good agreement between simulation and scaling theories of a brush-type PEG.
    Journal of Chemical & Engineering Data 05/2014; 59(10):140508125237007. DOI:10.1021/je500157b · 2.05 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The clinical use of phospholipid-coated quantum dots (QDs)–photosensitizer complexes as therapeutic nanoagents depends on colloidal stability of these complexes and efficiency of Förster resonance energy transfer from QDs to bound photosensitizer molecules. In this study, we demonstrate modification of CdSe/ZnS QDs with different phospholipids such as 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (PEG–DPPE); 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000 (PEG–DOPE) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and the complex formation with photosensitizer chlorin e6 (Ce6). QDs were successfully solubilized in water by coating QDs with PEG–DPPE and PEG–DOPE phospholipids. However, an attempt to solubilize QDs using PEG-free phospholipids (DOPC) was ineffective. While QDs modified with DOPC:PEG–DOPE mixtures at molar ratios of 1:1 and 2:1 showed long-term stability in aqueous solution, colloidal solution of QDs modified by DOPC:PEG–DPPE (molar ratio 2:1) was unstable. We showed that Ce6 forms a stable complex only with QDs coated with unsaturated phospholipids PEG–DOPE and DOPC:PEG–DOPE. Close localization of Ce6 molecules to the core of QDs ensures efficient energy transfer from QDs to bound Ce6 molecules that is crucial for its further application in photodynamic therapy of cancer.
    Journal of Nanoparticle Research 07/2014; 16(7). DOI:10.1007/s11051-014-2508-x · 2.28 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Magnetofluorescent nanocomposites (MFNCs) providing a single nanoscale platform with multimodal properties are gaining momentum in biological manipulation, biomedical imaging and therapies. In this work, we report the preparation of MFNCs integrating MnFe2O4 magnetic nanoparticles (MNPs), CuInS2/ZnS quantum dots (QDs) and poly(ethylene glycol)-b-poly(lactide-co-glycolide) (PEG-PLGA) in a tetrahydrofuran (THF)/water solvent system. Through sonication and quick solvent displacement, multiple nanoparticles of each type are co-encapsulated within the hydrophobic core of PEG-PLGA micelles. The developed fabrication process is simple and fast. Moreover, due to the low toxicity of CuInS2/ZnS QDs, the fabrication process is environmentally benign. The fabricated MFNCs were further characterized regarding their fundamental physical, chemical and biological properties. Results reveal that the MFNCs possess high (Mn + Fe) recovery rates, and the optical properties and magnetic relaxivity of the MFNCs are sensitive to the MNP:QD mass ratios in the fabrication. Furthermore, the MFNCs present excellent stability in aqueous solutions, minimal cytotoxicity, and capability for bioconjugation. This study opens an avenue for the MFNCs to be employed in broad biological or biomedical applications.
    Colloids and Surfaces A Physicochemical and Engineering Aspects 10/2014; DOI:10.1016/j.colsurfa.2014.10.017 · 2.35 Impact Factor

Full-text (2 Sources)

Available from
May 20, 2014