Detection of Single Cell Activity by Using Fluorescence-Based Multiscale pH and Oxygen Sensors

This paper reports a parallel monitoring method for single cell metabolic and respiration activity by using a microarrayed pH and oxygen sensor. Optical sensor film was prepared by immobilizing fluorescein isothiocyanate (for pH sensor array) or dichlorotris (1,10-phenanthroline) ruthenium (II) (for oxygen sensor array) onto a diamond like carbon sputtered slide glass. Micro well (10 mum i.d.) array was prepared with carbon black doped PDMS (or epoxy resin) onto the sensor film. The prepared microarrayed pH and oxygen sensor enabled independent pH and oxygen sensing in each micro well, and the difference of metabolic and respiration activity of single cell (mouse lymphocyte) could be detected in a microarrayed pH and oxygen sensor.