Formulation, characterization, and in vitro evaluation of quantum dots loaded in poly(lactide)-vitamin E TPGS nanoparticles for cellular and molecular imaging.
We developed a novel system of poly(lactide acid)-d-alpha-tocopheryl polyethylene glycol 1000 succinate (PLA-TPGS) nanoparticles (NPs) for quantum dots (QDs) formulation to improve imaging effects and reduce side effects as well as to promote a sustainable imaging. The QDs-loaded PLA-TPGS NPs were prepared by a modified solvent extraction/evaporation method, which were then characterized by laser light scattering (LLS) for size and size distribution; field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and transmission electron microscope (TEM) for surface morphology. Surface chemistry of the QDs-loaded PLA-TPGS NPs was analyzed by X-ray photoelectron microscopy (XPS) and Fourier transform infra-red spectroscopy (FTIR). Encapsulation efficiency of the QDs in the polymeric nanoparticles was measured by inductively coupled plasma optical emission spectrometry (ICP-OES). The photostability of the QDs formulated in the PLA-TPGS nanoparticles was investigated as changes in the florescence intensity versus the irradiation time. Confocal laser scanning microscopy (CLSM) was used to image the cellular uptake of the QDs-loaded NPs by MCF-7 cells. Methylthiazolyldiphenyl-tetrazolium (MTT) assay was employed to assess the viability of MCF-7 cells incubated with the QDs formulated by the PLA-TPGS NPs versus the mercaptoacetic acid (MAA)-coated QDs. It was found that the QDs formulated in the PLA-TPGS NPs can result in higher fluorescence intensity and higher photostability than the bare QDs as well as lower cytotoxicity than the MAA-coated QDs.
Pan
Jie
J
Department of Chemical & Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117576, Singapore.
Wang
Yan
Y
Feng
Si-Shen
SS
D045744:Cell Line, Tumor; D002477:Cells / Q000648:ultrastructure*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011091:Polyesters / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000378:metabolism; D045663:Quantum Dots; D017550:Spectroscopy, Fourier Transform Infrared; D013194:Staining and Labeling / Q000379:methods; D014810:Vitamin E / Q000031:analogs & derivatives* / Q000378:metabolism
D011091:Polyesters; D014810:Vitamin E; D011092:Polyethylene Glycols; C033616:poly(lactide); C014225:tocophersolan