Fig. 1

A Custom-made LED module. 48 individually dimmable LEDs for each well of a MTP. An optical isolator prevents interference between individual wells of the MTP. B Combination of the LED module with a μRAMOS device. The LED module is mounted below the MTP. μRAMOS measures the partial pressure of oxygen in each well and calculates the resulting OTR. C Photograph of the assembled device with A. thaliana plant seedlings. Translucent MTPs were used for illustration purposes. For online monitoring, black MTPs with transparent bottoms were used