The potential to isolate and regulate the biodynamics of single cells is significant in drug design and screening. However, pre-existing experimental reports in single-cell drug screening must yet provide multiple-dose gradient studies, to accurately predict drug–single cell interactions and performance. In a new report in Microsystems and Nanoengineering, Shaofei Shen and a team of scientists in life sciences and medicine in China solved this problem by creating a multi-concentration gradient generator.