A New Approach for the Spectroscopic Detection of Different pH-Values
The objective of the present work was the development of a micro-pH meter for the determination of the pH value within bioreactors with a volume of up to 200 μl in total. Two different prototypes of optodes were designed and tested. In a first approach spectroscopic analysis of bromothymol blue in a micro-sized-channel structure was carried out utilizing glass fibers, enabling measurements in sample volumes down to the range of picoliters. In a second approach a different illumination system consisting of a RGB-sensor and a LED light source was used. Phenol red was successfully applied as the pH indicator for this setup.
C. Sommitsch, M. Ionescu, B. Mishra, E. Kozeschnik and T. Chandra
C. Rogge et al., "A New Approach for the Spectroscopic Detection of Different pH-Values", Materials Science Forum, Vol. 879, pp. 1606-1611, 2017