Flexible Microchambers That Gently Sense Oxygen

A sensor sheet that can non-invasively measure oxygen levels could aid drug discovery and quality control of cultivated cells for regenerative medicine.

AsianScientist (Jan. 4, 2016) – Researchers at the University of Tokyo have developed a flexible sheet-type sensor that allows non-invasive measurement of cellular oxygen metabolism. Their results have been published in PLOS ONE.

Although evaluation of cellular quality and activity is important in the field of drug development and regenerative medicine, conventional cellular analysis methods tend to hurt or modify the measured cells.As a result, researchers have been searching for sensors that allow noninvasive measurement of cultivated cells and that can be easily removed after measurement.

The research group, led by Associate Professor Takanori Ichiki at the Graduate School of Engineering, the University of Tokyo and Nikon, has developed a flexible sheet-type sensor that allows sensitive and non-invasive measurement of cellular metabolism of cultivated cells or sliced tissues and can easily be removed after use.

The sensor comprises a flexible and transparent polymer sheet having a number of small holes, called as microchambers, whose diameter is as fine as that of hair. On the bottom of each hole, a thin sensing layer containing a phosphorescent metal complex shows a phosphorescence emission response dependent on the oxygen concentration.

Top: An array of microchamber structures integrated with a thin phosphorescent sensing layer (red color) below fabricated on a transparent flexible polymer sheet. Bottom: Cross-sectional image of the sensor. Credit: Takanori Ichiki/University of Tokyo.
Top: An array of microchamber structures integrated with a thin phosphorescent sensing layer (red color) below fabricated on a transparent flexible polymer sheet. Bottom: Cross-sectional image of the sensor.
Credit: Takanori Ichiki/University of Tokyo.

When placed on cultivated cells or sliced sections of three dimensional tissues, the sensor was able to obtain sensitive and non-invasive measurements of oxygen consumption.

“The combined use of the sensor and an automated optical measurement system to monitor the phosphorescence enabled high-throughput sensing of cellular oxygen consumption at 100 points per minute. We successfully monitored the oxygen metabolism of cancer cells on a Petri dish, and furthermore, demonstrated the mapping of oxygen consumption rate of rat brain slices,” said Ichiki.

“This sensor sheet is suitable for mass production and we expect will have widespread applications in drug discovery and in quality control of cultivated cells for regenerative medicine.”

The article can be found at: Kojima et al. (2015) Flexible Sheet-Type Sensor for Noninvasive Measurement of Cellular Oxygen Metabolism on a Culture Dish.

———

Source: University of Tokyo.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Asian Scientist Magazine is an award-winning science and technology magazine that highlights R&D news stories from Asia to a global audience. The magazine is published by Singapore-headquartered Wildtype Media Group.

Related Stories from Asian Scientist