Research On The Interaction Of Gold Nanorods As A Direction Probe With Cells In Endocytosis Based On Dark Field Imaging

Last decade witnessed the explosive growth of nanomaterial-based bioimaging and biomedicine.In situ real time,single nanoparticle tracking(SPT)technology as a powerful method of analyzing biological processes and the organizational structure of living organisms plays an important role in biomedical research.As a fundament issue,the interactions between nanoparticle and single live cells have attracted increasing interest in biochemical and biological research.Previously,versatile techniques including optical microscopy,ICP-AES and TEM,have been exploited for studying the great impacts of size,shape and surface chemistry on the nanoparticle-cell interactions.Due to the lack of technology for the process dynamics analysis,most studies are currently concerned only with the quantitative determination of nanoparticle internalization.We based on dark field fiber imaging technology for rotational and translational tracking of single nanorods and demonstrated its applications in the study of nanoparticle-cell interaction kinetics.In this article,we performed the research in the following three parts:In the second chapter,We use the traditional dark field microscope to establish a simple and effective dual-mode single particle tracer method.The method uses the corresponding relationship between the spatial constellation of gold nanorods and the color of the scattering spot,and analyzes the color change of the probe during the movement,can realize the simultaneous analysis of the position information and the spatial conformation information.In the third chapter,using traditional dark field microscopy,we achieved real-time monitoring of single gold nanorods interacting with cells in endocytosis.The translational kinematics and rotational dynamics information of the gold nanorods in the process of endocytosis with the cells were elucidated,and the translational kinetic and rotational dynamics information of the gold nanorods in the process of interaction with the cells were elucidated.The clathrin-dependent endocytosis of the gold nanorods enters the cells in the direction of the membrane perpendicular to the membrane.It is proved that the traditional dark field imaging technique is a good technique to study the interaction between nanoparticles and cells,and obtain more biological information.In the fourth chapter,we introduced a dual-channel scattering imaging technique for rotational and translational tracking of single nanorods.This dual-channel scattering imaging was realized by adding a beam-splitter device containing a polarizer in the light collecting path of light scattering microscopy.After imaging on a color CCD,the polar angle and azimuth angle of a gold nanorod were determined according to the color of the images in the two channels respectively.The localization information of the nanorod was obtained from the unpolarized imaging channel.Compared with previous techniques,this method is more robust for intuitively determining rotational and translational information of single nanorods with higher precision during the nanoparticle-cell interaction process.It can be anticipated that this technique is promising for the applications in the study of nanomaterial-based bioimaging and biomedicine.we use the dual-channel scattering imaging technique established to measure the three-dimensional spatial configuration of gold nanorods in the cell environment.The three-dimensional spatial orientation of the interaction between different surface-modified gold nanorods and cells was studied,and the translational and rotational behaviors of different modified gold nanorods were investigated.This method is of great significance for studying the conformational and rotational kinetic dynamics of biomolecules at nanomaterials or nanoscale.