Profiling methane emission in the Baltic Sea: Cryptophane as in-situ chemical sensor
Final Report Abstract
A laboratory prototype of a Kretschmann-configuration surface plasmon resonance sensor with angular detection has been built and tested. With this prototype the changes in refractive index of a polymer or a fluid applied on a glass surface can be detected. Optical configuration, camera module and electronics for control and storage have been designed to be incorporated in an underwater housing. Such housing has been designed and built to make up an underwater sensor. The sensors sensitive layer is coated on SPR slides, making it comparatively easy to change the sensor slide regularly in case this should prove necessary. It would also allow to change the functional molecule (the cryptophane-A in case of dissolved methane detection) to target different constituents in the seawater. By changes of the incident and reflecting angles the sensor set-up can be adjusted to different refractive index ranges, making it suitable also for the direct detection of the refractive index of seawater (which, however, was not subject of this project). Routines for post processing of the SPR spectra have been established. There have been a number of surprises during the course of the project. A surprise was that the Spreeta SPR sensor chips couldn’t be sourced as intended, meaning that one intended approach to get an in situ sensor fairly quickly had to be abandoned. The polymer used for the sensor coating by Boulart et al. (2012), Sylgard 184, was discontinued, so for this an alternative solution had to be found as well.
Publications
- (2017). PDMS membranes as sensing element in optical sensors for gas detection in water. Sensing and Bio-Sensing Research, 16, pp. 74-78
Torino, S., L. Conte, M. Iodice, G. Coppola, R. Prien
(See online at https://doi.org/10.1016/j.sbsr.2017.11.008) - Entwicklung eines SPR-Sensors für die Methan-Messung. Jahresbericht 2017 des Leibniz-Instituts für Ostseeforschung Warnemünde
Prien, R.
