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Title: ndocytosis of a Single Mesoporous Silica Nanoparticle into a Human Lung Cancer Cell Observed by Differential Interference Contrast Microscopy

Abstract

The unique structural features of mesoporous silica nanoparticles (MSN) have made them very useful in biological applications, such as gene therapy and drug delivery. Flow cytometry, confocal microscopy, and electron microscopy have been used for observing the endocytosis of MSN. However, flow cytometry cannot directly observe the process of endocytosis. Confocal microscopy requires fluorescence labeling of the cells. Electron microscopy can only utilize fixed cells. In the present work, we demonstrate for the first time that differential interference contrast (DIC) microscopy can be used to observe the entire endocytosis process of MSN into living human lung cancer cells (A549) without fluorescence staining. There are three physical observables that characterize the locations of MSN and the stages of the endocytosis process: motion, shape, and vertical position. When it was outside the cell, the MSN underwent significant Brownian motion in the cell growth medium. When it was trapped on the cell membrane, the motion of the MSN was greatly limited. After the MSN had entered the cell, it resumed motion at a much slower speed because the cytoplasm is more viscous than the cell growth medium and the cellular cytoskeleton networks act as obstacles. Moreover, there were shape changes around the MSNmore » due to the formation of a vesicle after the MSN had been trapped on the cell membrane and prior to entry into the cell. Finally, by coupling a motorized vertical stage to the DIC microscope, we recorded the location of the MSN in three dimensions. Such accurate 3D particle tracking ability in living cells is essential for studies of selectively targeted drug delivery based on endocytosis.« less

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Ames Laboratory (AMES), Ames, IA
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
939192
Report Number(s):
IS-J 7306
Journal ID: ISSN 1618-2642; TRN: US200823%%42
DOE Contract Number:  
DE-AC02-07CH11358
Resource Type:
Journal Article
Journal Name:
Anal Bioanal Chem
Additional Journal Information:
Journal Volume: 391; Journal Issue: 6; Journal ID: ISSN 1618-2642
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; CELL MEMBRANES; CYTOPLASM; DIMENSIONS; ELECTRON MICROSCOPY; FLUORESCENCE; GENE THERAPY; LUNGS; MICROSCOPY; NEOPLASMS; SHAPE; SILICA; VELOCITY

Citation Formats

Sun, Wei, Fang, Ning, Trewyn, Brian, Tsunoda, makoto, Slowing, Igor I, Lin, Victor S. Y., and Yeung, Edward S. ndocytosis of a Single Mesoporous Silica Nanoparticle into a Human Lung Cancer Cell Observed by Differential Interference Contrast Microscopy. United States: N. p., 2008. Web. doi:10.1007/s00216-008-2162-1.
Sun, Wei, Fang, Ning, Trewyn, Brian, Tsunoda, makoto, Slowing, Igor I, Lin, Victor S. Y., & Yeung, Edward S. ndocytosis of a Single Mesoporous Silica Nanoparticle into a Human Lung Cancer Cell Observed by Differential Interference Contrast Microscopy. United States. https://doi.org/10.1007/s00216-008-2162-1
Sun, Wei, Fang, Ning, Trewyn, Brian, Tsunoda, makoto, Slowing, Igor I, Lin, Victor S. Y., and Yeung, Edward S. Sat . "ndocytosis of a Single Mesoporous Silica Nanoparticle into a Human Lung Cancer Cell Observed by Differential Interference Contrast Microscopy". United States. https://doi.org/10.1007/s00216-008-2162-1.
@article{osti_939192,
title = {ndocytosis of a Single Mesoporous Silica Nanoparticle into a Human Lung Cancer Cell Observed by Differential Interference Contrast Microscopy},
author = {Sun, Wei and Fang, Ning and Trewyn, Brian and Tsunoda, makoto and Slowing, Igor I and Lin, Victor S. Y. and Yeung, Edward S},
abstractNote = {The unique structural features of mesoporous silica nanoparticles (MSN) have made them very useful in biological applications, such as gene therapy and drug delivery. Flow cytometry, confocal microscopy, and electron microscopy have been used for observing the endocytosis of MSN. However, flow cytometry cannot directly observe the process of endocytosis. Confocal microscopy requires fluorescence labeling of the cells. Electron microscopy can only utilize fixed cells. In the present work, we demonstrate for the first time that differential interference contrast (DIC) microscopy can be used to observe the entire endocytosis process of MSN into living human lung cancer cells (A549) without fluorescence staining. There are three physical observables that characterize the locations of MSN and the stages of the endocytosis process: motion, shape, and vertical position. When it was outside the cell, the MSN underwent significant Brownian motion in the cell growth medium. When it was trapped on the cell membrane, the motion of the MSN was greatly limited. After the MSN had entered the cell, it resumed motion at a much slower speed because the cytoplasm is more viscous than the cell growth medium and the cellular cytoskeleton networks act as obstacles. Moreover, there were shape changes around the MSN due to the formation of a vesicle after the MSN had been trapped on the cell membrane and prior to entry into the cell. Finally, by coupling a motorized vertical stage to the DIC microscope, we recorded the location of the MSN in three dimensions. Such accurate 3D particle tracking ability in living cells is essential for studies of selectively targeted drug delivery based on endocytosis.},
doi = {10.1007/s00216-008-2162-1},
url = {https://www.osti.gov/biblio/939192}, journal = {Anal Bioanal Chem},
issn = {1618-2642},
number = 6,
volume = 391,
place = {United States},
year = {2008},
month = {5}
}