Atomic Force Microscopy And Optical Tweezers Investigations Of Biophysics Properties Of Erythrocyte

As light source of precision sensor in late model photoelectric instrument discipline, Laser opens up a new approach for application study of life science and biophysics.Atomic Force Microscopy is one of the single element techniques, which in real time can image, observe and analysis to vital cell at high resolution condition. It utilizes a beam of low power laser focus on the sensitive and elastic micro-cantilever, and the sharp probe tip underneath micro-cantilever scans by optical grating pattern at observed sample surface, and interaction forces exist between probe tip and sample. Photoelectric explorer accepts the side-play mount of probe, which correspond with the difference of reflected light intensity, to acquire the information about the observed sample surface topography. When three dimensional piezo-electric scanner alter motion mode. Interaction forces have exerted between probe tip and sample because of the variable distance, and generate relative information about the spectrums of force-distance curve. Investigations of biophysics properties can make by collecting relative the information on sample surface.Laser Optical Tweezers is a three-dimensional optical potential well formed dynamics effect, which is the process of momentum transmission between laser and substance. It could capture and control the nanometer scale of microscopic particle. Optical sensor could be a great variety of modes, such as capture, suspend, sorting, fusion, chip and install. It could investigate intermolecular dynamic and static mechanics property quantitatively, and characterize qualitatively the biontic vital process. Optical Tweezers just as a micro-probe, which can real time detection and control with the property of detected no-bruising and remote-operated, to the internal and external structure of biologic particles in vivo. As the new mode control techniques of precision photo electricity instrument, Atomic Force Microscopy and Laser Optical Tweezers are the hotspots of applied research in the new field of biophysics' technique and innovation nowadays, which have the potential capacity of science and extensive prospect of application.There are three research aspects about this thesis:Firstly, Elasticity properties of erythrocyte membrane measured using force curve of Atomic Force Microscopy. The deformability of membrane cytoskeleton protein network and the elasticity mechanics capability of erythrocyte membrane were directly influenced by the subtle changes of human erythrocytes' living environment. Elasticity properties of erythrocyte membrane surface were measured using force curve of atomic force microscopy, by collecting relative information about the spectrums of force-distance curve, and analyzing the living erythrocyte's properties of elasticity, adhesiveness, and osmotic fragility in physiological environment. The investigation indicated that the elasticity properties of erythrocyte membrane and deformability of cytoskeleton network were related to many factors of physiological solution, e.g. solute ingredients (glucose and electrolyte crystals), concentration and osmotic pressure et al. The research can be used to gain novel insights into native membrane dynamic and structure, and further provide the basis for the application of AFM in clinical diagnosis of the cellular membranopathy.Secondly, Atomic Force Microscopy observed and analysed to the morphology and vital of erythrocyte with ph-dependent changes. Effects of pH on micro-morphology characteristic of living erythrocyte in autologous plasma were observed by using atomic force microscopy. The characteristic absorption spectrums of intracellular hemoglobin were detected and analyzed by ultraviolet spectrum scanning technique. The investigation indicated that complicated physiology regulates and controls process, such as red blood cell membrane elasticity deformation, Cyto-membrane liquid crystal state phase transition, the change of hemoglobin configuration, membrane cytoskeleton protein network reassembling or despiralization, and membrane surface electric charge density reapportion were directly influenced by the gentle changes of pH valve in autologous plasma environment. Further, the remarkable diversities of erythrocyte carrying-oxygen ability were appeared in the different pH conditions. The research can be used to gain novel insights into the relationship of cirumferential organization with physiology dependency relationship of the erythrocyte and blood microrheology in extreme degrees of pH valves environment, and provide the basis for the application in clinical diagnosis and experiment study.Thirdly, Optical tweezers and Atom Force Microscope studied and observed to the living environment of Vital Erythrocytes. Laser single optical tweezers captured vital human erythrocytes, and carried out gripping, dragging, and localize in plasma physiological environment. Microcosmic morphology characteristics of living erythrocytes were observed by using Atom Force Microscope and Environment Scanning Electron Microscope technologies. The experiment studies revealed Atom Force Microscope observed vital human erythrocytes that incubated at different temperatures in plasma physiological environment, that surface microstructure of the cell membranes were shapely sensitive to the altered temperature increasingly, and that liquid crystalline state bio-membrane were slightly perturbed and happened phase transition. In the optical tweezers experiment, the captive erythrocytes were encaged in the three-dimensional laser optical potential well, and able to well maintain physiology characteristic property and intact shapes. Moreover, the surface of cell membranes exist interaction forces. The investigation indicated the developed laser optical tweezers, which was based upon the principle of optical press, not only can capture and manipulate the micron-scale of vital biological particles, but also it is a unique and effective supplementary means that provide the fashion of agile and intact control and the mode of dynamic observed pattern in real time, would apply to study vital erythrocytes' observe in the optimum physiological environment.In the thesis Atomic Force Microscopy and Optical Tweezers investigations independently provide complementary data towards the understanding of biophysics properties of vital erythrocyte.