Generation of hanging drops with defined solution concentrations using a sliding hanging drop chip

Traditionally, hanging drop method has been widely used for three-dimensional (3D) cell sphere culture, which in comparison to two-dimensional (2D) cell culture provides a cell culture environment to better mimic the in vivo conditions. Recently, it has been shown that microfluidic technology can provide attractive tools for hanging drop cell culture due to its ability of handling low volume liquid and potential of building high-throughput systems. In this paper, we present a new approach which can be used to build a simplified hanging drop chip system integrated with drug testing function. Without using other external equipment, cell culture and drug application processes can be easily done by using a conventional pipette and sliding the chip.