title: Shape Effect on Particle-Lipid Bilayer Membrane Association, Cellular Uptake, and Cytotoxicity.
abstract: Although computer simulation and cell culture experiments have shown that elongated spherical particles can be taken up into cells more efficiently than spherical particles, experimental investigation on effects of these different shapes over the particle-membrane association has never been reported. Therefore, whether the higher cellular uptake of an elongated spherical particles is a result of a better particle-membrane association as suggested by some calculation works or a consequence of its influence on other cellular trans-membrane components involved in particle translocation process, cannot be concluded. Here, we study the effect of particle shape on the particle-membrane interaction by monitoring the association between particles of various shapes and lipid bilayer membrane of artificial cell-sized liposomes. Among the three shaped lanthanide-doped NaYF4 particles, all with high shape purity and uniformity, similar crystal phase, and surface chemistry, the elongated spherical particle shows the highest level of membrane association, followed by the spherical particle with a similar radius, and the hexagonal prism-shaped particle, respectively. The free energy of membrane curvature calculated based on a membrane indentation induced by a particle association indicates that among the three particle shapes, the elongated spherical particle give the most stable membrane curvature. The elongated spherical particles show the highest cellular uptake into cytosol of human melanoma (A-375) and human liver carcinoma (HepG2) cells when observed through a confocal laser scanning fluorescence microscope. Quantitative study using flow cytometry also gives the same result. The elongated spherical particles also possess the highest cytotoxicity in A-375 and normal skin (WI-38) cell lines, comparing to the other two shaped particles.
authors.forename: Thapakorn
authors.initials: T
authors.lastname: Tree-Udom
authors.forename: Jiraporn
authors.initials: J
authors.lastname: Seemork
authors.affiliation: School of Materials Science, Japan Advanced Institute of Science and Technology , Nomi 923-1211, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Shigyou
authors.affiliation: School of Materials Science, Japan Advanced Institute of Science and Technology , Nomi 923-1211, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Hamada
authors.forename: Naunpun
authors.initials: N
authors.lastname: Sangphech
authors.forename: Tanapat
authors.initials: T
authors.lastname: Palaga
authors.forename: Numpon
authors.initials: N
authors.lastname: Insin
authors.forename: Porntip
authors.initials: P
authors.lastname: Pan-In
authors.forename: Supason
authors.initials: S
authors.lastname: Wanichwecharungruang
mesh_terms: D002277:Carcinoma / Q000378:metabolism; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D003198:Computer Simulation; D003600:Cytosol / Q000378:metabolism; D004705:Endocytosis; D005434:Flow Cytometry; D056945:Hep G2 Cells; D006801:Humans; D028581:Lanthanoid Series Elements / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry; D008113:Liver Neoplasms / Q000378:metabolism; D008545:Melanoma / Q000378:metabolism; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles; D019301:Oleic Acid / Q000737:chemistry; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry
chemical_list: D028581:Lanthanoid Series Elements; D008051:Lipid Bilayers; D008081:Liposomes; D019301:Oleic Acid; D011092:Polyethylene Glycols
keywords: ellipsoid particle; elongated spherical particle; endocytosis; membrane curving; upconverting nanocrystals