Simple-to-Operate Approach for Single Cell Analysis Using a Hydrophobic Surface and Nanosized Droplets.

Microfluidics-based technologies for single-cell analysis are becoming increasingly important tools in biological studies. With the increasing sophistication of microfluidics, cellular barcoding techniques, and next-generation sequencing, a more detailed picture of cellular subtype is emerging. Unfortunately, the majority of the methods developed for single-cell analysis are high-throughput and not suitable for rare cell analysis as they require a high input cell number. Here, we report a low-cost and reproducible method for rare single-cell analysis using a highly hydrophobic surface and nanosized static droplets. Our method allows rapid and efficient on-chip single-cell lysis and subsequent collection of genetic materials in nanoliter droplets using a micromanipulator or a laboratory pipette before subsequent genetic analysis. We show precise isolation of single cancer cells with high purity using two different strategies (i- cytospin and ii- static droplet array) for subsequent RNA analysis using droplet digital polymerase chain reaction (PCR) and real-time PCR. Our highly controlled isolation method opens a new avenue for the study of subcellular functional mechanisms, enabling the identification of rare cells of potential functional or pathogenic consequence.