Cell Morphology Detection And Its Application Based On Electric Impedance Flow Chip

Cell morphology represents a basic biological feature,and cell morphology analysis provides specific information for exploring the physiological and pathological status of cells.At present,the main method of cell morphology analysis is Cytochemical staining.The cells were first chemically stained and then observed under a microscope.This method needs to be operated by professionals and analyzed by artificial naked eye observation.The operation process of this method is complex and has high professional skills for operators.In addition,there is also a certain rate of misjudgment.Electrical impedance chip has been used in cell counting,classification and so on in recent years.However,the study of cell morphology based on microfluidic impedance has been rarely reported.In view of the above two problems,this paper studies the orientation of particles in the pipeline flow based on the flow electrical impedance technology,,and extracts the characteristics of the electric pulse signal.Cell-level particles of different shapes(rod-shaped and spherical)are classified.In addition,this method was applied to the calculation of yeast budding proportion in the process of yeast proliferation.The variation of budding rate in the process of yeast proliferation was analyzed.The Specific tasks include:In order to realize the directional focusing of different shape particles,the shear force of particles in channel flow is analyzed,and a kind of microfluidic chip with three-stage contraction-oriented focusing and coplanar electrode is designed.Compared with the design of microfluidic chip using sheath flow technique and dielectric electrophoresis technology to realize particle directional focusing,the chip has the advantages of simple fabrication,convenient operation and good directional focusing effect.A set of flow electrical impedance detection system is constructed.The micro-fluidic chip is mainly bonded by PDMS and single-sided glass electrode and welded to the pcb board.The main part of the detection circuit conclude a direct digital frequency synthesizer and a cross-locked phase-locked amplifier,which is used to measure the impedance information of particles passing through the microfluidic chip.The upper computer software displays the data returned by NI data acquisition card on LabVIEW and recognizes the pulse signal by MATLAB.At the same time,the pulse width and pulse height-width ratio of the electric pulse signal are used for the first time as an important characteristic parameter to distinguish the different rod-shaped particles from the spherical particles.After the theoretical verification,we use this method to distinguish the different shapes of budding yeast and the single yeast in the process of yeast proliferation,and analyze the budding situation in the proliferative stage.This method can quickly calculate the budding proportion of yeasts.Compared with the traditional manual counting method,this method is faster and more accurate.