چكيده به لاتين
Biotechnology is one of the fields which has been grown significantly in recent years and the need for manufacturing and control of the biological systems in micro/nanoscale felt strongly in that. Atomic force microscopy invention as a device capable of touching and even manipulating cell, is a great progress in this way. But in the application of the AFM in the manipulation process, the modeling of the different phases before contact until movement and reaching to the goal matters. One of the important cases in this process is the material of the particle in contact with the AFM which affects the particle's deformation during the contact and the manipulation process. So, in this thesis first mechanical properties of the healthy and cancerous cells of the breast such as elasticity module, adhesion, viscoelastic properties, creep function, bending and axial rigidities were extracted. The goal of extracting these properties in addition to applying in the manipulation, is the comparison between healthy and cancerous cells properties using that the changes of the cell according to getting cancer would be investigated and take advantage of the results in diagnosis and studying the progress of the disease. In the following, based on inefficiency of the elastic contact models for biological cells which show damping in addition to elastic properties, elastic models were developed to viscoelastic. BCP, Tatara, MD, PT, and COS are empirical and semi-empirical models which have been developed to viscoelastic and after simulation for linear and nonlinear cell mechanics models and investigating the results it became obvious that the BCP model has the closest results to experiments. On the other hand, between the cell mechanics models the Kelvin-Voigt has better and more acceptable results in addition to its simplicity. According to various geometries between biological and nonbiological particles, viscoelastic models were developed in general form and for any geometry which included roughness. Results showed that these models are also in good compatibility with experimental results for different geometries. Modeling and simulation of the first and second phase of the manipulation can affect increasing accuracy and minimizing experiments' errors, so in this thesis the first and second phase of the manipulation were developed first using developed contact models and also extracted propertis and then done for bean-shaped particle. Simulations of the elastic and viscoelastic states were compared which results show that the critical force in the viscoelastic state is less than elastic which is explainable due to the damping properties and consequently the acceleration reduction of the deformation. Atomic force microscopy is applied in drug delivery, nano-surgery, tissue production and etc. so, the phase after the particle's movement matters. In this thesis, the routing of the viscoelastic particles has been optimized using genetic algorithm. The real image of the HN-5 cells was processed and the path planning among these cells as stationary obstacles is done. To increase accuracy and since there are moving obstacles in particle's path, three moving obstacle were considered with undefined profile. On the other hand, because of accuracy importance and also cell and tool damage, the cost function included AFM error, particle deformation and the applied force on the tool which is minimized. Results were compared with the previous works and verified which gave the similar path among similar obstacles.
