Versatile fabrication and integration method of optical oxygen sensors in organ-on-chips

Oxygen concentration is an essential parameter in in vitro cell cultures as it affects cell viability, cellular activity, cell differentiation, and can be a measure for cellular response. Organ-on-chip (OoC) devices provide an in vitro cell culture method, aiming to mimic the in vivo situation better than conventional cell culture methods. Oxygen control in these OoC devices is very meaningful especially for organs with inherently large oxygen concentration gradients, such as the gut. Here, we show a versatile fabrication method for optical oxygen sensor patches based on platinum tetrakis (pentafluorophenyl) porphyrin (PtTFPP) in polystyrene (PS). The PtTFPP/PS sensors show a linear Stern Volmer calibration plot. The proposed fabrication method allows abundant design freedom regarding both the sensor patches (size and shape) and integration (site and number of patches) in a typical two-channel OoC device.