Three-dimensional tracking and temporal analysis of liposomal transport in live cells using bright-field imaging.
Gold nanoparticles (AuNPs) confined in liposomes of diameters around 200 nm produce strong scattering signal owing to surface plasmon resonance, and therefore bright-field optical tracking of the AuNP-encapsulating liposomes can be conducted in living cells. Using an optical profiling technique called noninterferometric wide-field optical profilometry and a bright-field tracking algorithm, the polynomial-fit Gaussian weight method, we analyze three-dimensional (3D) motion of such liposomes in living fibroblasts. The positioning accuracy in three dimensions is nearly 20 nm. We tag the liposome membranes with fibroblast growth factor-1 and reveal the intracellular transportation processes toward or away from the nucleus. On the basis of a temporal analysis of the intracellular 3D trajectories of AuNP-encapsulating liposomes, we identify directed and diffusive motions in the transportation processes.
Tsai
Feng-Ching
FC
Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan.
Tai
Lin-Ai
LA
Wang
Yu-Jing
YJ
Xiao
Jian-Long
JL
Hsu
Tsi-Hsuan
TH
Yang
Chung-Shi
CS
Lee
Chau-Hwang
CH
D000818:Animals; D002478:Cells, Cultured; D003584:Cytological Techniques / Q000379:methods*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D006046:Gold / Q000737:chemistry; D021621:Imaging, Three-Dimensional; D008081:Liposomes / Q000737:chemistry / Q000378:metabolism*; D051379:Mice; D008853:Microscopy / Q000379:methods*; D053758:Nanoparticles / Q000737:chemistry; D013194:Staining and Labeling / Q000379:methods; D059008:Time-Lapse Imaging / Q000379:methods*
D008081:Liposomes; D006046:Gold