Inkjet automated single cells and matrices printing system for matrix-assisted laser desorption/ionization mass spectrometry.

The ability of single or several cells introduction onto substrate simply would be a useful tool for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). In this study, we aimed to establish a sample introduction method for pattering cells to the substrate by inkjet technology. Inkjet driving, substrate surface and relative humidity were optimized for single or several cells introduction. Single type cell solution and MALDI matrix solution were automatically printed onto ITO glass substrate which was hydrophobic modified under humidity controlled condition. Then the substrate was inserted to MALDI-MS and cells sample solution provided several peaks from phospholipids. The inkjet technique enables us to print single and subcellular on the substrate with the range of a few hundred micrometers. This diameter would be useful for targeting by laser of MALDI-MS. Our technique provides a new platform for MALDI-MS analysis in single or several cells to get a wide information from one sample.