A Microfluidics Based Cell Culture Device with Controlled Temperature Gradient

Cell culture is an extensively used technique for studying the behavior and growth of cells in response to different conditions. Examining the effect of temperature variation on cells helps in understanding the characteristics of cancer cells and may help in developing therapeutic procedures. To study the effect of this variation, we propose to use a microenvironment with a programmable temperature gradient. Microfluidics based cell culture devices offer advantage of providing a controlled environment, effectively. The study focuses on creating a microfluidic cell culture device with a controlled temperature gradient. The device consists of two components– a microchannel (18mm×6mm) that holds the cell suspended in culture media and integrated multiple temperature sensors that detect the temperature in the microchannel. Soft lithography of Polydimethylsiloxane was used to fabricate the microchannel. The chromium temperature sensor, which is essentially a resistive pattern, was designed and fabricated using UV lithography technique. To measure the local temperature in a controlled gradient, integrated sensors are placed across the channel. These sensors give a measurement of the temperature inside the channel on the cold and hot regions. In order to provide this gradient, a custom built hotplate was devised which creates a difference of about 3˚ C across the width (6mm) of the channel. First, the designed sensors were calibrated and a linear relation between temperature and voltage was found. The device was evaluated by monitoring the temperature gradient across the channel for 6 hours. Cell compatibility of MCF-7 breast cancer cells was tested in the fabricated device with the set conditions and it can be used for in vitro experiments that last for hours