Cell printing draws inspiration from Chinese woodblocks

Los Angeles Times : It is common for researchers to use inkjet printers to place living cells in orderly patterns for experiments. However, inkjet printers are limited in how small and how flat a drop they can make, have relatively low survival rates for cells during the process, and can be very expensive. A new alternative that improves in all those areas is based on ancient Chinese woodblock printing techniques. Kai Zhang of the Houston Methodist Research Institute and his colleagues created silicone stamps that are cut with a series of canals. Regularly spaced along each canal are small hook shapes. Pulling cell-filled fluid through the canals by vacuum results in individual cells being trapped in each hook. The stamp is then placed on a surface and deposits the cells in an array pattern separated by just 5 µm. Zhang’s group tested the stamps with HeLa cells to compare the cells’ metastatic potential and with neurons to see how the cells grew connections. Although slower than inkjet printers and unable to print multiple layers of cells, the stamps had a nearly 100% cell survival rate and were significantly cheaper than a custom inkjet printer.