Preliminary Study Of A Cell Culture System Based On Microfluidic Chip

Cell culture technology is the basis of cell biology research and it occupies a veryimportant position in the field of biotechnological research. Depending on somecommon-used devices such as cell culture bottles and plates, conventional cell culturecannot accurately reproduce the actual in vivo microenvironment. Benefited from thedevelopment of microfluidic technology since the1990s, there are considerableprogress and new approaches on cell culture. The size of the channel of microfluidicchip is generally in tens to hundreds of micrometers, which has the similar size withcells. In addition, controlling the flow in a microchip is easy to be achieved andconsumption of reagents and cells can be saved. Owing to these incomparableadvantages, microfluidic cell culture technique has already been widely used in cellmigration, drug screening, cell differentiation, and some other fields.Based on the study of conventional cultural methods, a kind of microfluidic chip isdesigned and fabricated for cell-culture experiment. The initial aim is to search formethods for base coating, sampling, exchanging the culture medium, and cell passage.However, manual operation such as exchanging cell medium every eight hoursinevitably increases the chance of contamination and leads to considerableinconvenience. To overcome these problems, we have set up an automatic microfluidicchip cell culture system on the basis of our previous work and present experimentalconditions. Our research mainly includes the design and microfabrication ofmicrofluidic chip, the method implementation of temperature control and multi-stepsample control, the observation by the CCD and relevant analysis, as well as thesummary of the experimental results.First, a kind of microfluidic chip suitable for cell culture is designed, and thesubstrate is an ITO transparent conductive glass. ITO glass is a unique material becauseof its characteristics such as transparency and good electric and heat conduction. Cellculture system is mainly made up of highly transparent organic polymer materials,polymethyl methacrylate (PMMA). In order to find out the most suitable temperatureconditions for cell growth, this study evaluates a multi-physical field for key factors byusing finite element analyzing software COMSOL Multiphysics4.3b. The differentdistribution of temperature inside the microchip structure is simulated by varying thevoltage amplitude and its applied position. Thanks to notable benefits of microchips such as small size and high heat conduction, accurate display and control of the culturetemperature is realized with the help of XMT61intelligent PID temperature controller.Continuous transport of culture media can be used to realize perfusion culture.After receiving the corresponding command sent from the upper computer,electromagnetic valve conversion and the flow rate of the injection pump are controlledby a single chip microcomputer and injection pump, respectively, so as to adjust theflow precisely.We set up an automated culturing platform for continuous on-chip cell cultureexperiments. Hepatoma cells whose initial density in cell suspension is about106,usingthe system to study the hepatoma cells growthing in different widths channel, to take thefoundation of designing the size of the microfluidic channel. Endothelial cells werecontinuously cultured more than72hours in the system, which preliminarily validatesthe feasibility of this new experimental device...